PHA 624 Med Micro Final

who to test for HIV

"Opt-out" policy for persons *13-64* in all healthcare settings High-risk behavior Infection suspicion

ectoparasite

"a parasite that lives on the external surface of another living organism" - e.g. lice, ticks

PaO2/FiO2 ratio

"efficiency" rating of pulmonary oxygen exchange used in critically ill pts receiving more than 50% FiO2 and whose PaO2 <=100mmHg

scarlet fever

"strep throat with a rash" caused by GAS, mostly 5-12yo, same tx as strep mild illness, but needs abx to prevent rare but serious long-term health problems colonized in person's nose and throat, droplets in cough or sneeze, sharing meals, contact with sores from skin infections very red sore throat, fever (>101), red rash with sandpaper feel, whitish coating on tongue or back of throat, strawberry tongue, HA, N/V, abdominal pain, swollen glands, body aches long-term effects: rheumatic fever (inflammation of heart, joint, skin, and brain), kidney disease, OM, throat abscesses, pneumonia, arthritis Erythrogenic/pyrogenic exotoxin produces rash, 1-2 days post fever, rash fades 3-4 days post onset & peels

*medical parisitology

"the study and medical implications of parasites that infect humans"

Dr. North Bordatella pertussis summary

"whooping cough" observe: fever, malaise, paroxysms of rapid fire cough diagnosis: growth media-GNR P in DTaP vaccine DOC-erythromycin

vaginal candidiasis

"yeast infection"-severe itching/burning commonly associated with antibiotics bacterial infection often self-diagnosed as candidiasis (2/3 are actually bacterial)

Pneumococcus

#1 cause of bacterial pneumonia and meningitis in adults and OM in children sx: productive cough, rust-colored sputum, fever, rigors, dyspnea, pleuritic chest pain (sharp on inspiration), characterized by consolidated lobar pneumonia 20-30% of pneumococcal pneumonias cause sepsis and 20-30% die S. pneumo, dueling lancets, alpha hemolytic, GPC in pairs pneumolysin-exotoxin partially digests red blood cells and produces green halo polysaccharide capsule protects from phagocytosis extremely immunogenic, but there are 84 serotypes 34,000 invasive disease cases in 2013 reservoir-many people (esp children) colonized and asymptomatic transmission-droplet and direct/close contact; casual contact infrequent incubation: 1-3d; communacability: while ill or 24h post abx tx DOC: penicillin (20% resistant and growing) Pneumovax, Prevnar 23 and 13 vaccines

Infections Leading to Sepsis

#1: Lungs (most common site of infection: PNA) #2: Abdomen #3: Urinary tract

oral candidiasis

("Thrush") Babies; denture users Can progress into Candida esophagitis

acute pharyngitis

(mostly viral) GAS-Streptococcus pyogenes (only 10-30% all pharyngitis)

white piedra

(sub)tropical, superficial infection of hair on head or groin caused by yeast like fungi of the genus Trichosporon: T. inkin, T. asahii, or T. mucoides microscopic exam reveals hyphal elements, arthroconidia (rectangular cells resulting from the fragmentation of hyphal cells, and blastoconidia (budding yeast cells) will form cream, dry, wrinkled colonies within 48-72h at room temperature mycologic media without cycloheximide will inhibit Trichosporon swelling along the hair strand are soft and pasty and may be easily removed by running hair between thumb and forefinger, does not damage shaft tx: topical azoles, improved hygiene, shaving of the infected hair

*uncomplicated UTI tx overview

*3-5d* ALL YOU NEED TO KNOW FOR TEST DOC for E. coli, Proteus mirabilis, Klebsiella pneumoniae -TMP-SMX, nitrofurantoin, fosfomycin x1 dose, ciprofloxacin (FQ), levofloxacin (FQ) DOC for Enterococus faecalis -Ampicillin, amoxicillin, vancomycin (if allergic to PCN), fosfomycin x1 dose (for VRE) DOC for S. saprophyticus -1st generation cephalosporins or TMP-SMX

*complicated UTI tx overview

*7-14d* ALL YOU NEED TO KNOW FOR TEST DOC E. coli-1st, 2nd, 3rd-generation cephalosporins; TMP-SMX; FQ DOC Klebsiella and Proteus mirabilis- 1st, 2nd, 3rd-generation cephalosporins; FQ DOC Enterococcus-Ampicillin or vancomycin +/- AG DOC P. aeruginosa-Antipseudomonal PCN (piperacillin/tazobactam) +/- AG; ceftazidime; cefepime; FQ; carbapenem DOC Enterobacter- FQ; TMP-SMX; carbapenem DOC Proteus and Serratia-3rd generation cephalosporin; FQ DOC Aceinetobacter-carbapenem? DOC. S. aureus-Penicillinase-resistant PCN (nafcillin, oxacillin, dicloxacillin) ; vancomycin (for MRSA)

sterile body sites

*Blood Cerebral spinal fluid (CSF)* Pleural/Peritoneal/Synovial fluid Tissues *Lower respiratory tract* Bladder

UA report

*Color (might be orange in UTI)* *Clarity (might be cloudy in UTI* Glucose Bilirubin Ketone Specific gravity pH (might be elevated in Proteus) *Protein (may be present in UTI)* Urobilinogen *Nitrite (Pseudomonas and gram positive will be negative)* *Occult blood* *Leukocytes* Microscopic *-WBCs* *-RBCs* *-Epithelial cells (if asymptomatic may be contaminated sample)* *-Bacteria* -Amorphous sediment -Mucus -Casts -Crystals

community UTI

*E. coli*, other GNR (K. pneumoniae, P. mirabilis, Morganella morganii), Enterococcus, Staph saprophyticus, GBS

*diagnostic tools

*microscopy,* C&S, serology-indirect vs direct ELISA, rapid Ag and toxin tests, molecular identification, CBC, flow cytometer blood fluid analysis, general chemistry analysis

HCV testing

*persons born 1945-1965*, those at increased risk, HCV antibody test If result is positive-check HCV RNA prior to initiation of ART, test for genotye to guide ART selection, and liver biopsy to determine extent of liver damage

hepatitis B phases of infection

Immune tolerant phase-highly replicative/low inflammatory phase -Incubation Period - 45 to 160 days (average: 120 days) -High serum HBV DNA levels, highly infectious -HBeAg secretion -ALT levels are normal (<19 U/L for females and <30 U/L for males) Immune-active (clearance)phase -Decreased HBV DNA levels -Ongoing secretion of HBeAg -Marked increases in ALT levels -Intermittent flares of hepatitis -The hallmark of transition from the HBeAg-positive immune-active to -inactive phases is HBeAg seroconversion Inactive Chronic Hepatitis B (CHB) phase -HBV DNA levels are low or undetectable -ALT levels are normal Anti-HBe is present -Liver histology shows minimal necroinflammation, but variable fibrosis reflecting previous liver injury during the HBeAg-positive immune-active phase Chronic HBV -HBeAg positive -HBeAg negative --Active/Inactive carrier state --Persons with HBeAg-negative CHB tend to have lower serum HBV DNA levels than those with HBeAg-positive CHB and are more likely to experience a fluctuating course.

toxoplasmosis tx

Immunocompromised: pyrimethamine PLUS sulfadiazine or clindamycin Immunocompetent: treatment usually not indicated Newborns with congenital toxoplasmosis: Pyrimethamine, sulfadiazine and leucovorin x 12 months

vaccine importance

Impact on global public health Changes in the role of pharmacists Role in emerging/potential public health threats 17.1 million deaths averted by measles vaccination

ulcers transmissible

In US, 25M suffer from peptic ulcers, H. pylori causes >80% GNR, motile, microaerophilic, embeds through mucus into wall Pepto-Bismol bismuth salts inhibit H. pylori, metronidazole, ampicillin and/or tetracycline

ebola risk assessment-high

In any country: -Percutaneous (e.g., needle stick) or mucous membrane exposure to blood or body fluids from a person with Ebola who has symptoms -Direct contact with a person with Ebola who has symptoms, or the person's body fluids, while not wearing appropriate personal protective equipment (PPE) -Lab processing of blood or body fluids from a person with Ebola who has symptoms while not wearing appropriate PPE or without using standard biosafety precautions -Providing direct care in a household setting to a person with Ebola who has symptoms In countries with widespread transmission or cases in urban areas with uncertain control measures: -Direct contact with a dead body while not wearing appropriate PPE

Zika virus

Increased reports of birth defects and Guillain-Barré syndrome Vectors: Ae. aegypti and Ae. albopictus) Vertical or congenital to fetus during pregnancy or during child birth Sex Blood transfusions Symptoms similar to other illnesses spread through mosquito bites (Dengue and Chikungunya) Generally no or mild symptoms Rare hospital visitation Symptoms last several days to a week. Very rarely fatal Fever Rash Headache Joint pain Conjunctivitis (red eyes) Muscle pain dx: -Case and travel history --Including unprotected sex with partner who has traveled to or lives in endemic country -Blood and urine test --Low sensitivity and specificity because of viral localization in other body fluids (semen)

treatment and control Giardia

Infected individuals should be treated because Giardia can persist and lead to severe malabsorption syndromes and weight loss Drug of choice: Metronidazole (Flagyl) or Nitazoxanide with furazolidine. Acceptable alternatives - Quinacrine, Tinidazole, Albendazole, Paramomycin -85% effective parasite clearance Giardia is too wide spread in distribution to be eliminated: Control involves measures that prevent the ingestion of substances contaminated with fecal material 1. Health promotion and Education -Improve personal hygiene- hand washing, sanitation and food handling -Reduce person-to-person transmission 2. Special attention to personal hygiene in high risk institutions: Day care centers, etc. 3. Treatment of latent house-hold members 4. Socio-economic situation in developing countries is a hindrance -Public health measures to protect: Water supplies from contamination -Tourists: Not to drink tap water without additional treatment if purity is questionable 5. Boiling or Iodine treatments -Kills Giardia cysts: But standard chlorination does not

tinea nigra tx

Infection responds well to topical therapy: Whitfield ointment - a salicylic acid and benzoic acid in a suitable base, such as lanolin or vaseline. The original ointment contains 3% salicylic acid and 6% benzoic acid, but other ratios are also used. azole creams terbinafine

Enterocolitis

Inflammation involving the mucosa of both the small and large intestine.

GI intoxication

Ingestion of foods/water containing preformed bacterial toxins/poisons Starts very quickly (no incubation period)-S. aureus and C. botulinum

*empiric therapy

Initial therapy started in the absence of definitive microbiologic pathogen identification. Empiric therapy may be mono-, combination, or broad-spectrum, and/or multidrug in nature.

infection gaining entry into internal environment

Injection by biting vectors Disruption of tight junctions and adherens junctions that seal epithelial cells - Helicobacter pylori Use of extracellular polysaccharide (capsules, slime, and mucous layers, hiding in clots - S. aureus) Excretion of toxins lethal to phagocytic cell (Leukocidin C toxins) Use of host molecules as opsonins for uptake (Vaccinia virus, Mycobacterium tuberculosis, Listeria monocytogenes) Receptor-mediated endocytosis [Streptococcus pneumoniae, Salmonella enterica (typhi)]

medication classes for HIV

Integrase Inhibitors-block integrase needed for HIV-1 to make copies CCR5 Inhibitors-blocks CCR5 protein on the CD4 cell to prevent entry Protease Inhibitors-block protease needed for HIV-1 to make copies Nucleoside/Nucleotide RT Inhibitors (NRTIs)-block reverse transcriptase needed for HIV-1 to make copies Non-Nucleoside/Nucleotide RT Inhibitors (NNRTIs)-bind and alter reverse transcriptase needed for HIV-1 to make copies PK enhancers-boosters for some ART (e.g. cobicistat and ritonavir) PAI-post-attachment inhibitor-mAb binds to CD4 receptors to block viral entry Fusion/Entry Inhibitors-block HIV-1 from entering the CD4 cells

nematodes

Intestinal roundworms: -Ascaris (Giant intestinal roundworm) -Enterobius (Pinworm, threadworm) -Necator / Ancylostoma (Hookworm) -Trichuris (whipworm) -Strongyloides Tissue roundworms -Trichinella spiralis - trichinosis Round worms; appear round in cross section, they have body cavities, a straight alimentary canal and an anus

Intestinal Coccidia

Isospora, Sacrocystis, Cryptosporidium, Cyclospora, Toxoplasma some have 2 host life cycle Schizogony-binary fission; Sporpgony-sexual reproduction acid-fast stain, oocytes do not stain with iodine or trichrome Sarcocystis suihominis (intermediate host-pig), bohivihominis (cow), lindermanni (human, definitive host unknown-muscle infection) infective stage: sarcocysts in meat (intestinal); oocysts from animal feces (muscle)

The AVIAN H5N1 virus has raised concerns about a potential human pandemic because:

It is especially virulent. It is being spread by transported domestic poultry. It can be transmitted from birds to mammals and in some limited circumstances to humans.

chromoblastomycosis dx

KOH wet mount-dry crusty material from the surface of lesions -dark brown multicellular structures, 5-12 microns in diameter that divide by transverse septation (sclerotic bodies, medlar bodies, copper-penny bodies, muriform cells) medlar bodies-facilitates survival of organism in host tissues tissue stains for biopsy specimens-sclerotic bodies very well seen fungal culture with actidione and antibiotics

cultures and KSPs

KSP-key select pathogens 1. Blood cultures: R/O sepsis, osteomyelitis, meningitis, or pneumonia; KSPs S. aureus, S. pneumoniae, E. coli, K. pneumoniae, P. aeruginosa 2. Throat cultures: R/O strep throat (S. pyogenes/GAS); KSPs S. pyogenes/GAS, N. gonorrhea, C. albicans 3. Sputum cultures: R/O pneumonia or TB; KSPs S. pneumonia (CAP), S. aureus, P. aeruginosa, K. pneumoniae (HAP) 4. Spinal fluid cultures: R/O meningitis, unreliable for encephalitis; KSPs N. meningitis, S. pneumoniae. H. influenza 5. Stool cultures: R/O enterocolitis, or dysentery (bloody diarrhea); KSPs Shigella, Salmonella, Campylobacter, E. coli O157 6. Urine cultures: R/O cystitis or pyelonephritis; KSPs E. coli, Enterobacter, Proteus, E. faecalis, S. saphrophyticus 7. Genital tract cultures: R/O gonorrhea, chlamydia, or syphilis; KSPs N. gonorrhea, Chlamydophila trachomatis, Treponema pallidum 8. Wound cultures: R/O large variety of aerobes and anaerobes; KSPs B. fragilis, S. aureus, S. pyogenes (abscesses), C. perfringens (trauma), S. aureus (surgical), Pasteurella (dog/cat bite)

*general chemistry analysis

Kidney function (Creatinine, Blood Urea Nitrogen) Liver function (Bilirubin, Liver enzymes) C-reactive Protein (CRP) / ESR Procalcitonin (PCT)

characteristic signs of measles

Koplik's spots-small red-based lesions with blue-white centers on buccal mucosa rash-red macropapular-spreads from head to face to neck to torso by day 3 and disappears in same sequence

*terbinafine

Lamasil, synthetic antifungal, mostly topical, PO for tinea unguium lipophilic: accumulates in fat, skin, and nails active against most dermatophytes (tinea)

*furuncle

Large, raised, nodular extension of folliculitis resulting from spread of infection to surrounding tissues

hookworm life cycle

Life cycle Adult worms live in the intestine and excrete eggs in the feces In the absence of latrines, eggs contaminate soil and develop in warm, damp conditions eggs hatch and infective filariform larvae develop in about one week and remain infective in soil for many weeks filariform larvae penetrate the skin when a person walks barefoot in the soil larva migrate from the skin to the lungs via the lymphatic and blood systems larvae penetrate the capillary wall to enter the alveolus Larvae are propelled up the respiratory tree to the epiglottis where they are swallowed Develops to adult stage in upper intestine; adult worms are fully mature after about 5 weeks Eggs are excreted in the feces Note: eating soil (pica) is a common practice. Ingested filariform larvae of A. duodenale can pass directly to the gut mucosa

If there's nitrate in the urine?

Likely P. aeruginosa or gram positive

Is there a vaccine available for adenovirus?

Live oral vaccine to prevent adenovirus types 4 and 7 in military recruits

*vectors

Living organisms bringing infectious organisms to a host mechanical and biological

vaccine ADR

Local: -Injection-site pain/swelling -Usually least severe & most frequent Systemic: -Examples: syncope, fever -Usually more severe, but less frequent Allergic: anaphylaxis (very rare), GBS

*Source Of Infection

Location, host, object or substance from which the infectious agent was acquired Places: nosocomial (health care facility) or community (not health care facility) Contaminated Body substances (fomite) - feces, blood, body fluids, respiratory secretions and urine Contaminated shared inanimate objects (fomite)- syringes

pseudohyphae

Long chains of yeast cells

butenafine

Lotrimin Ultra, anti-inflammatory, superior antifungal activity over terbinafine

Borrelia burgdorferi

Lyme disease-bullseye rash

*IgM

M for "im"mediate

major tropical diseases

Malaria 300-500 million affected Shistosomaiasis 200 million Filariasis (Lymphatic filariasis and Onchocerciasis) 120 and 85 million Leishmaniasis 12 million Trypanosomiasis (African trypanosomiasis and chagas disease ) 18 million Leprosy Tuberculosis Dengue fever The first five are all parasites

*Kahoot-Superficial infection with hyper and hypopigmented patches is caused by which fungus?

Malassezia furfur

pathology B. coli

Many infections are asymptomatic, organism feeding on bacteria at surface of mucosa. Severe infections - with the aid of hyaluronidase, the organism burrows into submucosa, producing ulcers. Morphology - Large, oval shape; two nuclei, 1 large kidney shaped (macronucleus) & 1 small micronucleus (micronucleus not often seen); body surface covered by longitudinal rows of cilia; cytostome present. Primary animal reservoir - pigs, monkeys.

tissue invasive toxins in Staph aureus

Many of the same as Strep pyogenes, as well as, lipases, penicillinase, staphylokinase, leukocidin, exfoliatin, and factors that bind complement Causes tissue destruction e.g. scalded skin syndrome

*Facultative parasites

May exit in a free-living state or as commensal, and may become parasitic under certain conditions

biological vectors

Microbes must propagate in the vector before they can be transmitted to a host.

MERS-CoV

Middle East Respiratory Syndrome-Coronavirus Formerly called novel coronavirus -Not the same coronovirus that caused SARS Newly identified virus, causes severe acute respiratory illness - first seen in April 2012 54 cases, including 30 deaths (55.6%) to date 8 countries, with 72% in Saudi Arabia No cases in U.S. Can spread from person to person during close contact -Families -Healthcare Several studies have identified MERS-CoV in high proportion of camels -Likely Reservoir Identical gene segment found in one bat Mode of transportation unclear -Respiratory? Foodborne? -Few primary cases with direct camel contact

sx of hookworms

Minor -Often itchy papules are found at the site where the larva penetrated the skin -There may be cough and wheezing as the larva migrates through the lungs Major -Hookworm anemia --Tiredness, aches and pains --Pallor --Breathlessness --Oedema

fungal habitats

Most clinically relevant fungi reside in the soil, in bird feces, on vegetation, or on the skin and mucous membranes of mammals. Some have distinctive ecologic and geographical niches.

infection gaining superficial entry

Most entries are through food and water, air, the bites of vectors The gastrointestinal tract, lungs, and genitourinary tract are part of the outside folded in Parasites are outside the internal environment of the body Some epithelial surfaces (e.g., nasopharynx, colon) are colonized by a vast array of microorganisms -Commensals - disease in individuals with weakened immune systems. -Pathogens - Neisseria gonorrhoeae, Helicobacter pylori etc.

H5N1 sx

Most patients infected with the H5N1 virus show initial symptoms of fever (38 C (100.4 F) or higher) followed by influenza-like respiratory symptoms, including cough, rhinorrhea, sore throat, and (less frequently) shortness of breath. Watery diarrhea is often present in the early stages of illness, and may precede respiratory symptoms by up to one week. Gastrointestinal symptoms (abdominal pain, vomiting) may occur and headache has also been reported.

molds

Multicellular filamentous, "fluffy" colonies consisting of branching tubular structures called hyphae Collection of intertwined hyphae called mycelium Vegetative hyphae act like roots, penetrating the supporting medium and absorbing nutrients Aerial hyphae project above the surface of the mycelium and bear the reproductive structures of the mold (often spread through the air)

acid-fast examples

Mycobacterium and Nocardia

acid-fast

Mycobacterium tuberculosis

tuberculosis pathogen

Mycobacterium tuberculosis (Mtb) most common (others M. bovis, M. africanum, M. microti, and M. canetti) rod, nonspore forming, slow growing (4-6w) aerobic bacteria intracellular-mostly in macrophages; humans as only known reservoirs for Mtb has complex, lipid-rich cell wall (mycolic acid)

exceptions to gram stain rules

Mycobacterium-weakly gram + but stain better using acid-fast technique Mycoplasma-have no cell wall (neither gram - or gram +) Legionella and Chlamydophila-weakly gram - but may be considered atypical (cause atypical pneumonia) Spirochetes-gram - cell wall, but are too small to see on a light microscope

bacteria with no cell wall

Mycoplasma

Atypical Respiratory Tract Infection examples

Mycoplasma pneumoniae AKA walking pneumonia; Chlamydophila pneumoniae, Legionella pneumophila AKA Legionaires' disease

gonorrhea

N. gonorrhoeae-gram negative intracellular diplococcus infects mucus-secreting epithelial cells evades host response through alteration of surface structures increasing resistance, fellatio (pharyngeal infection), susceptible to HIV RF: risky sexual behavior, urban residence, adolescent (particularly females), low socioeconomic status, drugs, prostitution, African American

Bacterial Meningitis Common Causes

N. meningitidis (meningococcal meningitis), S. pneumoniae (pneumococcal "), S. agalactiae (GBS "), H. influenzae, Listeria monocytogenes, gram - organisms (E. coli, Klebsiella, Enterobacter, etc.)

Meningococcal meningitis

N. meningitidis-gram (-) diplococcus transmission-direct contact or respiratory droplets differential sx: purpuric and petechial lesions common, Waterhouse-Friedrichsen syndrome, joint involvement vaccinations: Menactra, Menveo, Menimmune indicated in adolescents age 11-12 yo with a booster at 16 in addition to high risk populations (travelers to endemic areas, asplenic pts, outbreaks in daycare,military, dorm etc.)

Kahoot-lymphocyte that kills viruses and tumor cells

NK

CSF components in infection summary

NORMAL: clear, protein <50, glucose 50-60% of peripheral serum glucose, pH 7.4, WBC <5 (lymphocytes) BACTERIAL: WBC very high, PMNs, protein high, cloudy, low glucose VIRAL: WBC high, 50/50 PMNs/lymphocytes, cloudy or clear, protein 30-150, normal glucose MYCOTIC: WBC high, mostly lymphocytes, protein 40-150, may be slightly cloudy, glucose usually low

host defense mechanisms

Natural Barriers Innate Immune Defenses Adaptive Immune Responses

lymphocytes

Natural Killer Cells T-cells - cytotoxic adaptive immunity (cell-mediated) B-cells - antibody-driven adaptive immunity (humoral)

gram - obligate aerobes

Neisseria Pseudomonas Bordetella Legionella Brucella

GNC

Neisseria-aerobe

gram - examples

Neisseria-diplococci, Moraxella-diplococci, Treponema pallidum-spirochete everything else are rods or pleomorphic

common infectious causes of meningitis

Neonates: KEE, S. agalactiae, L. monocytogenes Infants: S. agalactiae, S. pneumonia, N. meningitidis, H. influenzae 2-50yo: S. pneumoniae and N. meningitidis >50yo: KEE, L. monocytogenes, S. pneumoniae, N. meningitidis

ketoconazole

Nizoral for tinea, candidiasis, blastomycosis, coccidiodomycosis, dandruff absorption best at low pH (antacids interfere!), does not enter CNS well

WNV tx

No vaccines or specific antiviral treatments available OTC pain relievers Supportive treatment and hospitalization for severe cases

does alcohol kill spores

No! Wash your hand really well and be careful!

gram + obligate aerobes

Nocardia (weakly acid-fast) Bacillus cereus

Kahoot-fungus-like bacteria with branching thin filaments similar to hyphae

Nocardia asteroides

What type of immunity is protective for echovirus?

None. There is no specific treatment or vaccine.

posaconazole

Noxafil-very broad spectrum (>1800 fungi!!!)

*culture-based diagnosis

Obtain appropriate specimen Perform microscopy (direct/wet mount or stained) Culture & identification Perform antibiotic susceptibility testing

*tinea barbae

Occurs on the beard area

*Negative (-) Stranded RNA Viruses

Old Pete's Rabid dog Filo fought Paul Bunyan in the Arena Orthomyxo, Paramyxo, Rhabdo, Filo, Bunya, Arenaviridae Carry RNA-dep RNA polymerase in their capsid which translates - strand into + *all are helical*

filiara

Onchocerca volvulus - Transmitted by the simulium black fly, this microfilarial parasite can cause visual impairment, blindness and severe itching of the skin in those infected Wuchereria bancrofti - The major causative agent of lymphatic filariasis Brugia malayi - Another microfilarial parasite that causes lymphatic filariasis

Toxoplasmosis

Only known hosts of Toxoplasma gondii are cats. Humans can become infected by eating undercooked meat, blood transfusion, vertical transmission, and ingestion of cat feces.

*infection

Organism harmfully invades Is infection required for bacterial-related disease? No! Toxins are there and they are not always killed by cooking. Staph toxins on food cause diarrhea even though you don't have a staph infection

naked DNA viruses

PARVO-single-stranded PAPOVA and ADENO-double-stranded all icosahedral

PAM dx and tx

PCR, CSF with amoebas, meningitis with negative results for bacteria and viruses difficult to treat-lack of studies because it's rare and difficult to diagnose ideal regimen includes amoebicidal drugs that can cross the BBB suggestion: amphotericin B, rifampin, fluconazole, azithromycin

What type of virus generally causes the common cold?

PICORNA (rhinovirus)

(+) stranded naked RNA viruses

PICORNA and CALICI-icosahedral

Kahoot-Which can cause the common cold?

PICORNA and CORONA

PARAMYXO

PIV (parainfluenza), pneumovirus (RSV), morbillivirus (measles), rubulavirus (mumps), hMPV (human metapneumovirus) enveloped (156-300nm), nonsegmented, -ssRNA, 5-8 x 10^6 Da, helical similar to orthomyxoviruses-larger; not segmented like influenza virus most common cause of bronchiolitis in children <3yo

H5N1 occupational exposure

Personal protective equipment. Those at risk of occupational exposure on affected or at-risk farms should wear personal protective equipment: 1. Protective clothing, preferably coveralls plus an impermeable apron or surgical gowns with long cuffed sleeves plus an impermeable apron 2. Heavy-duty rubber work gloves that may be disinfected; 3. Standard well-fitted surgical masks should be used if high-efficiency N95 respiratory masks (NIOSH-certified N-95 or equivalent) are not available. Masks should be fit-tested and training in their use should be provided 4. Goggles 5. Rubber or polyurethane boots that can be disinfected or protective foot covers that can be discarded. Those at risk of occupational exposure on affected or at-risk farms can be protected via antiviral prophylaxis (oseltamivir) or post-exposure prophylaxis. Antivirals should be readily available for the treatment of suspected and confirmed cases. Health monitoring: 1. Be aware of the early clinical signs of H5N1 infection, but also understand that many other common diseases - of far less health concern - will show similar early symptoms. 2. Check for these signs (especially fever) each day during potential exposure and for 14 days after last exposure. 3. Communicate any symptoms to a designated local physician and provide background information on exposure history.

bacterial energy sources

Phototrophs - use light as an energy source Chemotrophs - use chemical compounds as an energy source Autotrophs - use inorganic sources, such as ammonium and sulfide Heterotrophs - use organic carbon sources Chemoheterotrophs - use chemical and organic compounds, such as glucose for energy (includes all medically important bacteria). ***Obligate intracellular organisms are NOT capable of the metabolic pathways for ATP synthesis and MUST steal ATP from their host (ex. Chlamydia and Rickettsia)***

black piedra

Piedraia hortae asymptomatic superficial infection of the hair, primarily the scalp uncommon, tropical areas in Latin America and Central Africa reddish black branched hyphae held together by a cement-like substance as the culture ages, spindle-shaped ascospores are formed within specialized structures called asci that are produced in the rock-hard hyphal mass that surrounds the hair shaft treatment is easily accomplished with a haircut and proper washings

systemic protozoa

Plasmodium-malaria-P. falciparum, P. vivax, P. ovale, and P. malariae affect man Toxoplasma gongi-ingestion of cat feces can also lead to ocular problems Leishmania-sand flies, visceral, cutaneous, or mucocurtaneous Trypanosoma-hemoflagellates-sleeping sickness in Africa from Tsetse fly or Chagas disease in South America from Reduviid bug

measles complications

Pneumonia, eye damage, myocarditis, and encephalitis pregnancy complications: spontaneous abortion, premature delivery, and fetal death in 20% of cases...does not cause birth defects

PPSV23

Pneumovax; mostly for older adults; targets 25/84 capsular serotypes

*factors of fecal-oral transmission

Poor Personal Hygiene -Children e.g day care centers -Institutions e.g prisons, mental hospitals, orphanages -Food handlers Less Developed Countries -Poor sanitation; Endemic -Lack of indoor plumbing -Traveler's diarrhea Water-borne Epidemics -Water treatment failures Male Homosexuality -Oral-anal contact Zoonosis -Cryptosporidium -Giardia ? Control/Prevention improve personal hygiene especially institutions treat asymptomatic carriers eg, family members health education hand-washing sanitation food handling protect water supply treat water if questionable boiling iodine not chlorine

Reye's syndrome

Potentially serious or deadly disorder in children characterized by vomiting and confusion. Can be caused by taking aspirin while suffering from influenza.

Extra Pulmonary TB

Potts disease-spinal, Lupus vulgaris-skin, Scrofula-infected lymph nodes located in the neck (cervical tuberculous lymphadenopathy)

schistosomiasis tx, prevention, and control

Praziquantel: effective against all species S. haematobium: single dose (40 mg/kg) S. mansoni, S. japonicum: 2-3 doses of 30mg/kg Educate people to not urinate or defecate in fresh water supplies Eliminate snail vectors by making the water habitat unsuitable (increase water flow, remove vegetation) Provide piped water to avoid direct contact with cercariae Mass drug treatment of communities to reduce reservoir of infection

UTI detection

Presence of >/=100,000 colony-forming units (CFU)/ml indicative of UTI Some women can be symptomatic w/ <100,000 CFU/ml gram stain results within 24 hrs or sooner culture-gold standard -Identifies organism and its susceptibility to antibiotics -Results in 48 hrs

*colonization

Presence of microbe on or in the body Normal flora vs infection

Superficial Fungal Infections

Primary symptom is a pigment change of the skin with no systemic symptoms e.g. Pityriasis versicolor, Tinea nigra

*Opportunistic pathogens

Produce disease when the health and immunity of the host have been severely weakened by illness, malnutrition, or medical therapy.

subclinical or subacute illness

Progress from infection to resolution without clinically apparent symptoms

flagella

Protein filaments that extend from the cell membranes and help to propel the bacterium. Affixed to the bacterium by a basal body. The basal body spins which propels the bacterium toward or away from a chemical gradient (aka chemotaxis)

prion

Proteinaceous Infectious Particles

Which bug raises urine pH?

Proteus

Pseudomonas aeriginosa

Pseudomonas exotoxin A-same action as diphtheria toxin except it targets liver

phenazopyridine

Pyridium, Azo-Standard, Uristat, urinary analgesic, no antimicrobial properties most UTI sx respond quickly to abx therefore analgesic has little clinical role may mask sx of UTIs that are not responding to antimicrobial therapy controversial, AE: red-orange discoloration of body fluids, rash, hemolytic anemia

double-stranded RNA viruses

REO-icosahedral, naked

BV

RF: African American, risky sexual behavior in past 6mo, douching, lack of barrier protection, lack of lactobacilli (maintain pH through metabolism of glycogen) all lactobacilli produce lactic acid, some produce H2O2 (potent microbicide) -toxic to viruses such as HIV as well as bacteria not considered an STD but appears to be related to sexual activity overgrowth of a bacteria species normally present in vagina with anaerobics majority asymptomatic, malodorous (fishy) vaginal discharge, more common after intercourse or menses, may remit spontaneously Ansel Criteria for diagnosis-3 of the following: vaginal pH >4.5, presence of >20% per HPF of "clue cells" on wet mount, positive amine or "whiff" test, homogenous nonviscous discharge adherent to walls

viral keratitis

RF: contact lens HSV tx: trifluridine drops (primary), ganciclovir ophthalmic gel and vidarabine ointment (alternatives) 30% recurrence rate in 1y; consider prophylactic acyclovir 400mg BID for 12mo

*bacterial keratitis

RF: contact lenses, previous surgery, trauma with foreign bodies, Ocular Surface Disease, systemic conditions, ocular medications, corneal epithelial abnormalities characterized by: *pain and inflamed cornea, photophobia*, corneal opacification or ulceration, tearing, accumulation of pus (hypopyon) in the anterior chamber *S. aureus, S. pneumo, Pseudomonas*, GAS, Enterobacter, Bacillus, N. gonorrhoeae moxi- or gati-floxacin eye drops for S. aureus, S. pneumo, GAS, and Haemophilus tobramycin/gentamicin/piperacillin or levo- or cipro- for Pseudomonas (contacts) cephazolin +gent/tobra or vanc+ceftazidime for S. aureus, S. epidermis, S. pneumo, GAS, Enterobacter, Listeria (dry cornea, DM, immunosuppression)

vaginitis

RF: multiple sex partners, lower socioeconomic status, STD history, lack condoms almost always sexually transmitted, may be asymptomatic cause: Trichomonas vaginalis-single-celled, flagellated, anaerobic protozoan parasite-*only protozoan of the genital tract* associations with preterm rupture of membranes and delivery, increased risk of HIV acquisition and transmission dx: culture is the gold standard; DOC: metronidazole oral single dose

*Chlamydia

RF: young, risky sexual behavior, STI hx, OC use >50% of sexual partners acquire infection 60-70% risk of vertical transmission (azithromycin prophylactically) incubation period 7-21d, significant asymptomatic reservoir, reinfection common obligatory intracellular bacteria, infect columnar epithelial cells, survive by replication that results in the death of the cell two forms: EB (elementary body) and RB (reticulate body)

*Kahoot-bullet shaped virus

RHABDO

Which virus is the #1 cause of pneumonia in infants/children?

RSV

ebola virus diagnosis

RT-PCR-used to diagnose acute infection, more sensitive than ELISA, performed in select CLIA-certified laboratories RT-PCR sample collection-minimum 4mL whole blood in plastic non-heparin tubes, preserved with EDTA preferred (also used SPS, citrate, or clot activator) virus isolation can take several days and requires a biosafety level 4 lab immunohistochemical, histopathological=localize viral antigen on collected tissue serological testing for IgM and IgG with ELISA monitor the immune response in confirmed Ebola pts

epidemiology B. coli

Rarely found in USA. This is the only ciliate parasite of humans. Largest parasitic protozoan - trophozoite is 30-120 x 25-125 microns; the cyst averages 50 - 70 microns in diameter. Life cycle - The cyst is ingested via fecal contamination in environment; cysts excyst in the small intestine; trophozoites migrate to large intestines

Respiratory infections

Respiratory infectious diseases are mainly caused by viruses or bacteria that often interact with one another. A major portal of entry for infectious organisms It is divided into two tracts - upper and lower. -The division is based on structures and functions in each part. -The two parts have different types of infection.

rhinosporidiosis

Rhinosporidium seeberi, hydrophilic protist, bath with domestic animals chronic granulomatous disease of mucous membrane with friable polyps in nose, mouth, or eye (also genitals, urethra, or rectum) cannot be cultured, biopsy of lesion, nasal washing -contains sporangia and spores embedded in stroma of connective tissue and capillaries medical therapy is not useful and recurrence is common radical surgery-excision, electrocautery

*genital HPV RF in men

Risk increases with increasing number of recent and lifetime sex partners Being uncircumcised increases risk

Group B Strep

S. agalactiae

skin microbiome

S. epidermidis-inhabits up to 90% of outer skin surfaces S. aureus-most commonly just inside the nose and perineum Micrococci-accounts for up to 10% of bacteria found on outer skin surfaces Diphtheroids-commonly skin high in sebaceous glands (ex. P. acnes) Streptococci-predominate the oral flora and may spread from there to the skin GNR-Found on moist skin such as the axilla and between toes

CAP causes

S. pneumoniae (75% in adults), H. influenzae, atypicals, S. aureus (MSSA), GBS

Pneumococcal meningitis

S. pneumoniae-GPC transmission: respiratory droplets or previous colonization/infection differential sx: rashes are rare, hx of head trauma, chronically draining ear

SPI-1 and SPI-2

Salmonella pathogenicity island-1 and 2 binds to M cell (microfold) in Peyer's patches M-cells sample lumen, trancytose, and present to APCs and lymphocytes Sips/Ssps (salmonella-secreted invasion proteins), M cells may result in membrane ruffling and phagocytosis replicates in phagosome (tolerant to acid) spread from adjacent epithelial cells and lymphoid tissue

*carbuncle

Several furuncles joined together

*Brain anatomy protective mechanisms

Skull and meninges provide barrier BBB and BCSFB tightly regulate entrance and exit of molecules Immune system designed to attack pathogens prior to entry into CSF

Soil-Borne Bacteria Pathogens

Soil is the most complex ecosystem (heterogeneity). Home to 25% of Earth's species (biodiversity) which must compete for food and space. Excretion of compounds that kill or interfere with growth of nearby microorganisms (chemical warfare) can be isolated and used as antibiotics.

Gram - microaerophilic

Spirochetes (treponema, borrelia, and leptospira) and Campylobacter

tinea versicolor tx

Spontaneous cure has been reported, but the disease is usually chronic and persistent Treat with topical "azoles" or selenium sulfide shampoo For widespread infection, oral ketoconazole or itraconazole may be used

itraconazole

Sporonox, IV and PO (poor absorption), absorption increased with acids and decreased with antacids does not reach CSF, very broad spectrum highly lipophilic-fatty tissue accumulation

*apicomplexans

Sporozoa Characteristics: -Nonmotile, Intracellular parasites -Complex life cycles, Asexual/sexual reproduction Plasmodium - malaria -transmitted by Anopheles mosquito Cryptosporidium - diarrhea; AIDS related Toxoplasma - toxoplasmosis; AIDS related

How does the viral structure of echovirus 11 facilitate virus spread in the body?

Spread from throat and tonsils into the circulatory system (answer given in class)

SEB

Staph enterotoxin B-most potent of the 7 toxins #1 cause of bacterial food poisoning; profound GI response: anorexia, N/V/D resists digestion (HCl and proteases) and boiling for several minutes Superantigen-bypasses antigen processing - bridges MHC-II and T-cells, activating proliferation of T-cells. Triggers massive release of cytokines (IL-2, TNF-b, interferons) from intestinal lamina propria T-cells.

*honeymoon UTI

Staph saphrophyticus-most common UTI for newly sexually active women

Which UTI-causing bug is in clusters?

Staph saprophyticus

SSSS

Staphylococcal Scalded Skin Syndrome-cells of the outer epidermis separate from the underlying tissue and begin peeling off in sheets within 2d of onset cause: exfoliative toxins from S. aureus tx: Nafcillin for MSSA and vancomycin or linezolid for MRSA RF: tampons that are not changed regularly and the immunosuppressed

gram + facultative anaerobes

Staphylococcus, Bacillus anthracis, Corynebacterium, Listeria, Actinomyces

*How is the common cold treated?

Stay hydrated. ... Rest.Your body needs to heal. Soothe a sore throat. ... Combat stuffiness. ... Relieve pain. ... Sip warm liquids. ... Add moisture to the air. ... Try over-the-counter (OTC) cold and cough medications.

GI Tract Flora

Stomach acidity limits bacteria so bacteria counts are highest just after a meal and lowest just after inhestion. Helicobacter can still colonize this region, however. Small intestines contain 10^6-10^8 organisms/mL such as Streptococci, Lactobacilli, Bacteroides, and Bifidobacterium Colon contains 10^9-10^11 organisms/mL of up to 400 different species. 95-99% are anaerobic organisms like Bacteroides, Bifidobacterium, Clostridium, Eubacterium, and Peptostreptococcus.

Kahoot-Which genus is found in the normal flora of the mouth?

Streptococci

Group B Strep Meningitis

Streptococcus agalactiae-GPC, leading cause of neonatal meningitis transmission: GI/GU colonization in pregnant women then vaginal transmission If a mother tests positive: administer antibiotics during labor GBS vaccination for pregnant women under development

gram + examples

Streptococcus and Enterococcus-chain Staphylococcus-clusters Bacillus and Clostridium-spore forming rod Corynebacterium and Listeria-non-spore forming rod

viral assembly and release

Structural proteins and genome assemble into intact helical or icosahedral virion Naked virions - Released through host cell lysis or exocytosis Enveloped virions - Naked virion "buds" through the host cell lipid bilayer and takes a portion of the lipid bilayer with it

*virulence factors

Substances or products generated by infectious agents that enhance their ability to cause disease. Mediate the tissue damage and pathophysiology of infectious disease Four main categories -Toxins -Adhesion factors -Evasive factors -Invasive factors

Specimen Collection for the Eye

Surface of the eye infections: specimens are collected by swab or by corneal scrapings before topical anesthetics are applied Deep-seated infections: aspiration of the aqueous or vitreous fluid is performed Inoculate plates at bedside; seal and transport immediately to laboratory Volume is whatever you are able to collect

syphilis pathology

T. pallidum enters via skin and mucous membranes through abrasion during sexual contact or birth and travels via the circulatory system and lymphatic system throughout the body

Neurosyphilis

T. pallidum invades CNS at any stage of syphilis, may be asymptomatic acute syphilitic meningitis, meningovascular syphilis, general paresis (late), tabes dorsalis. (late) and ocular involvement neurologic involvement can occur decades after infection and is rarely seen

Congenital Syphilis

T. pallidum to fetus during any trimester and may lead to stillbirth, neonatal death, deafness, neurologic impairment, and bone deformities wide spectrum of severity-only severe cases are apparent at birth -early lesions (most common) <2yo, usually inflammatory -late lesions >2yo, immunologic and destructive

*(+) stranded enveloped RNA viruses

TOGA-icosahedral, FLAVI-icosahedral, CORONA-helical, RETRO-helical

*indirect tests for TB

TST (tuberculin skin test), serological (Ab detection), hematological (ESR)

Mantoux test

TST (tuberculin skin testin) 0.1mL of 5 TU (tuberculin units) PPD induration of >5mm after 72h is considered positive for people with HIV, recent close contacts with TB, suggestive xray for TB hx, people with organ transplants, and other immunosuppressed patients >10 for people from endemic areas, injection drug users, people who live or work in high-risk congregate settings, lab workers, people with medical conditions that put them at increased risk, <4yo, children or adolescents exposed to adults in high-risk categories >15 for people with no known risk factors for TB false negative: anergic (nonreactive to antigens-immunosuppressed e.g. HIV) false positive: BCG vaccination or nonTB mycobacteria infection positive PPD reaction usually 3-4 weeks after exposure only evidence of infection is lifelong positive skin test and radiographic evidence of calcification of granulomas in lungs and other organs

control of HPAI in Thailand

Thai government started supporting in-door keeping of ducks, offering feed subsidies, and constructing enclosures only sporadic outbreaks since 2005

*normal microbial flora

The body is made up of 10^13 cells but harbors 10^14 bacteria! We are outnumber 10:1. The bacteria may aid the host by producing nutrients or competing with pathogenic organisms for space. The bacteria may exist as commensals neither helping nor hurting. The bacteria may be harmful (e.g. dental caries, abscesses)

amebae

The definitive host ingests the infective cyst stage from fecal contamination in environment. The cyst passes into the small intestine & excystation occurs with transformation to the trophozoite stage. Trophozoites colonize the host, multiplying asexually via binary fission. They can remain near the lumen (non-pathogens) or invade the wall of the intestine & multiply (pathogens). Cysts and trophozoites are passed in the feces of the infected host.

*prevalence

The number of active cases at any given time

*portal of entry

The process by which a pathogen enters the body, gain access to a susceptible tissue, and cause disease. Potential modes of transmission are: penetration, direct contact, ingestion, inhalation

What properties of the coronavirus restrict the infection to the upper respiratory tract?

The spikes lock into the upper respiratory tract. Also, the lower respiratory tract are typically sterile due to macrophages and enhanced mucociliary clearance

*targeted/definitive therapy

Therapy targeted to a specific pathogen (usually after microbiologic identification). Targeted/ definitive therapy may be mono- or combination, but is not intended to be broad-spectrum.

*multidrug therapy

Therapy with multiple antimicrobials to deliver broad-spectrum therapy (i.e., to broaden coverage) for empiric therapy (i.e., where pathogen is unknown) or to potentially accelerate pathogen clearance (combination therapy) with respect to a specific pathogen(s) where the pathogen(s) is known or suspected (i.e., for both targeted or empiric therapy). This term therefore includes combination therapy.

general characteristics of protozoa

There are about 45,000 protozoan species; around 8000 are parasitic, and around 25 species are important to humans. Diagnosis - must learn to differentiate between the harmless and the medically important. This is most often based upon the morphology of respective organisms. Transmission - mostly person-to-person, via fecal-oral route; fecally contaminated food or water; other means include sexual transmission, insect bites or insect feces.

Is there a vaccine for EV-D68?

There is no specific tx and no vaccine, favorable studies with pleconaril

*How is the influenza virus transmitted?

Transmitted person-to-person by the aerosols created by coughing and sneezing

Zika tx

Treat the symptoms Rest Drink fluids to prevent dehydration No aspirin or other NSAIDs until dengue can be ruled out to reduce the risk of bleeding Take acetaminophen (Tylenol®) to reduce fever and pain

wet prep

Trichomonas & Yeast (Candida spp) Cervical swab mixed with saline

flagellate

Trichomonas vaginalis-no cyst stage, STI Giardia lamblia-intestinal malabsorption, TD, day cares, hikers

hemoflagellates

Trypanosoma and Leishmania (Baghdad boil transmitted by sand fly vector)

gram positive

Two layers: inner cytoplasmic membrane and thick outer peptidoglycan layer (60-99% peptidoglycan) low lipid content no endotoxins, periplasmic space, or porin channel vulnerable to lysozyme and penicillin attack

*Human Reservoirs

Two types of human reservoirs (Human sources of Infection) a. Acute clinical cases b. Carriers.

*how to classify strains of influenza A virus

Type (A) Place of original isolation Date of original isolation HA and NA type

What is the incubation period for SARS-CoV?

Typically 2-7 days, may be as high as 14

UTI tx in males

UTIs are considered complicated Treatment duration 10-14 days Some require longer treatment

yeasts

Unicellular fungi, reproduce by budding Moist mucoid or waxy colonies that resemble bacteria

yeast

Unicellular growth form of fungi, which reproduce by budding

alternating life cycle

Use different hosts at different stages of life Changing host behavior-schistosomes, Dracunculus medinensis (guinea worm) Acute diseases-"hit and run"-flu, measles, smallpox, polio Chronic diseases-dormancy-remains without killing host

anidulafungin

Used i.v. Active against Candida and Aspergillus Approved 2006 for invasive Aspergillosis

*Pathogens or infectious agents

Utilize the host's resources to multiply at the expense of the host Damage or interfere with the normal functioning of the host.

*vaccination vs immunization

Vaccination: administration of a vaccine Immunization: physiological response that confers protection from infection

voriconazole

Vfend for severe systemic infections and emerging fungi (very broad spectrum)

viral uncoating

Viral nucleic acid is released from the capsid into the nucleus or cytoplasm

abnormal CSF components in mycotic CNS infections

WBC 100-400 (normal <5) differential >50% lymphocytes protein 40-150 (<50) Glucose <30-70 (low usually) May be slightly turbid

abnormal CSF components in bacterial CNS infections

WBC 1000-5000 (normal <5) differential PMNs (lymphocytes) protein 100-500 (<50) Glucose <40 (45-80) Turbid (clear)

abnormal CSF components in viral CNS infections

WBC 5-500 (normal <5) differential 50/50 with PMNs and lymphocytes protein 30-150 (<50) Glucose <30-70 (normal) Turbid or clear

sepsis diagnosis via 2016 guidelines

We recommend that appropriate routine microbiologic cultures (including blood) be obtained before starting antimicrobial therapy in patients with suspected sepsis or septic shock if doing so results in no substantial delay in the start of antimicrobials (BPS).

*Factors influencing environment of disease transmission

Weather Housing Geography Occupational setting Air quality Food

*WNV

West Nile Virus

WNV

West Nile Virus-discovered in Africa in 1937, but not seen in US until 1999 Sx: asymptomatic 80%, febrile illness, HA, joint pain, vomiting, diarrhea, rash 20% humans, horses, and other mammals are dead in host-An infected individual who is bitten by a mosquito cannot pass it to another mosquito

*CBC

White blood cell count (WBC) Increased WBC suggests infection -- Neutrophilia points to bacterial -- Lymphocytosis (or neutropenia) suggest viral

types of vaccines

Whole cell: -Live attenuated -Killed/inactivated Toxoid Subunit, recombinant, and conjugate

lymphatic filariasis life cycle

Wucherichia bancrofti by Culex mosquitoes in India and Anopheline in Africa B. malayi and B. timori are transmitted mainly by Mansonia mosquitoes larval forms (microfilariae) taken up by female human infected with adult worms when the mosquito bites someone the infective filariform larvae enter the bite then migrate to the lymphatics and lymph glands larvae develop into adults over 3-12mo depending on the species of filarial worm

mycetoma dx

XR, CT, MRI, gross examination of grains, KOH mount of grains specimen grains or granules-pus, exudates, or biopsy eumycetoma 2-6 microns, wide interwoven hyphae with large, swollen cells (chlamydospores) at the margin of the lesion fungal (25 and 37) and bacterial media when eumycetoma is suspected, wash grains several times in NS with PCN and innoculate it on media with antibiotics

Which pathogen has V and W antigens?

Yersinia pestis

symptoms and lab diagnosis B. coli

abdominal pain and tenderness, tenesmus, nausea, anorexia, and watery stools with blood and pus; ulceration of the intestinal mucosa as with amebiasis can be seen as a secondary complication caused by a bacterial invasion examine feces for trophozoites and cysts

*Factors to Consider When Choosing an Empiric Antibiotic Therapy

ability of abx to penetrate infection, *most common: lungs, intra-abdominal, UTI* most likely pathogens, age, underlying diseases (DM, liver/renal failure, invasive devices), immune status (defects of Ig, neutropenia, splenectomy, immunocompromised), recent known infection pathogens, antimicrobials in past 3mo, tolerance and toxicity, abx susceptibility and resistance profile for institution

*Pathogenicity

ability to cause disease (# with disease/# infected) x 100

*Encystment

ability to form dormant cysts surrounded by a resistant outer covering

epidemic

abrupt and unexpected increase in the incidence of disease over endemic rates

antigenic shift

abrupt genetic recombination to create new viral strain; infrequent, but important

Gonorrhea complications in women

accessory gland infection (Bartholin's and Skene's) PID-may be asymptomatic or may present with lower abdominal pain, discharge, dyspareunia, irregular menstrual bleeding and fever Fitz-High-Curtis Syndrome (perihepatitis)

proteins in vaccines

acellular e.g. Fluvirin-purified hemagglutinin and neuraminidase

carbs in vaccines

acellular e.g. Pneumovax 23-purified mixture of capsular polysaccharides from Strep pneumo

nucleic acids in vaccines

acellular, called "third generation" vaccines, no current vaccines first generation-whole cell, second generation-subunit adjuvant use: CpG-1018 part of Heplisav-B plasmid DNA encoding specific antigens is injected leading to host cell production of antigens and a broad, sustained immune response

lipids in vaccines

acellular-included as antigens in whole cell vaccines, but more frequently used as adjuvants e.g. Squalene (basis of MF59 adjuvant in Fluad) and MPL (monophosphoryl lipid A-part of AS01B adjuvant in Shingrix)

What type of immune response would protect against adenovirus infection?

acquired (answer given in class)

Neurotoxin

act directly on central or peripheral nervous system -Staphylococcus aureus, Bacillus cereus

types of immunization

active: antigen exposure that produces protective response passive: direct immunoglobulin transfer used when a vaccine is not fast enough to save lives like rabies, doesn't last as long and is not as durable of a response

poliomyelitis

acute enteroviral spinal cord infection that can cause neuromuscular paralysis poliovirus-naked capsid; resistant to acid, bile, and detergents transmission person-to-person, via contaminated food and water, saliva, feces mild: sore throat, HA, fever, and nausea from multiplication in throat and intestines polioviruses adhere to receptors of mucosal cells in oropharynx and intestine, shed in throat and feces, some leak into blood most infections are short-term, mild viremia, can spread to spinal cord and brain neurotropic-infiltrates motor neurons of the spinal cord causing flaccid paralysis bulbar poliomyelitis causes damage of the respiratory organs requiring breathing treatments in an "iron lung"

AECB

acute exacerbation of chronic bronchitis; lower respiratory tract infection mostly viral, then M. pneumoniae, C. pneumoniae, S. pneumoniae, B. pertussis

pharyngitis

acute infection of oropharynx and nasopharynx viral causes most common followed by GABHS (group A beta-hemolytic strep) bacterial sx: swollen uvula, white spots, swollen tonsils, redness, gray furry tongue viral sx: swollen tonsils, redness *S. pyogenes*, group C strep, Arcanobacterium haemolyticum, C. pneumoniae, N. gonorrhea, Corynebacterium, M. pneumoniae, Francisella tularensis

ebola early clinical presentation

acute onset 8-10d after exposure (2-21): fever, chills, myalgia, malaise, anorexia after 5d: N/V/D, abdominal pain; other: HA, conjunctivitis, hiccups, rash, chest pain, SOB, confusion, seizures, hemorrhagic sx (18%) similar: malaria, typhoid fever, meningococcemia, Lassa fever-common in Africa

AOM

acute onset rhinitis, congestion, or cough, otalgia (pain-severe up to 75%), fever (<25%), lethargy, anorexia, vomiting, diarrhea, otorrhea (ear drainage) discolored, thickened, bulging, nonmotile eardrum (50% bilateral) S. pneumoniae, H. influenzae, Moraxella catarrhalis (only children) treat ear pain with APAP, IBU, topical analgesics like antipyrine/benzocaine (AB Otic, Allergen), Auralgan antihistamines and steroids not found effective tympanostomy tubes if 3+ episodes in 6 mo or 4+ episodes in a year (one recent) 40-70% viral, then S. pneumoniae, H. influenzae, Moraxella catarrhalis

management of hepatitis C

acute: no recommendation; guidelines are constantly changing chronic: 8-12w of oral therapy cure over 90% of people with few SE

HSV treatment

acyclovir, valacyclovir, famciclovir

epidemic keratoconjunctivitis

adenoviridae; usually local outbreaks like schools, work, and nursing homes Asia (especially Japan) but not generally found in US until an outbreak of 10,000 cases in the shipyards of Pearl Harbor in 1941

botulism sx

adults: diplopia (double vision), blurred vision, ptosis (drooping upper eyelid), slurred speech, dysphagia, dry mouth, muscle weakness infants: poor feeding, neck and peripheral weakness, constipation, resp failure

HPV treatment response

affected by number, size, duration, and location of warts, and immune status warts on moist surfaces and in intertriginous areas respond better to topicals many pts need several weeks-months of therapy, evaluate risk-benefit regularly locally developed and monitored tx algorithms assoc. with improved outcomes no evidence of superiority of particular txs

Clinical Management of Ebola

aggressive supportive therapy-IV fluid resuscitation, electrolyte repletion, hemodynamic support and critical care management if necessary, manage fever and GI sx, avoid NSAIDs, if multisystem organ failure-oxygenation, ventilation, correct severe coagulopathy, renal replacement therapy

treatment of chronic hepatitis B infection

alcohol and drugs can further damage or strain liver (herbal and Rx) acute: supportive care chronic-regular monitoring of disease progression, some pts get antivirals (lamivudine, telbivudine, adefovir, entecavir, tenofovir goals of therapy-not curable, increase chances of seroclearance, prevent progression to cirrhosis and HCC, minimize further injury immunomodulating agent like interferon

toxins

alter or destroy normal function of the host or its cells (exo or endotoxin) mostly produced by bacterial, but also certain fungal and protozoan pathogens diverse spectrum of activity and effect a wide variety of host target cells

In vitro IFN-γ Release Assay for TB

alternate to PPD skin test-immunoassay to measure IFN-gamma produced by sensitized Tcells stimulated by antigens-PPD antigens replaced with TB antigens -ESAT-6 (early secreted antigens target) and CFP-10 (culture filtrate proteins) advantages-differentiates between TB infections and BCG

*AG

aminoglycoside

four subdivisions of Phylum Protozoa

amoebae-Sarcodinia-pseudopodia flagellates-Mastigophora-long, whiplike flagella ciliates-Ciliata-propelled by sychronized wavelike motion of cilia sporozoans-lack specialized organelles of motility

polyenes

amphotericin, Nystatin (topical, Canidida, dermatophytes) selectively bind ergosterol in fungal cell membrane, altering membrane fluidity and producing pores and osmotic cell death. alter selectively permeability to K+ (and Mg2+) => Fungicidal Resistance due to altered sterols

adjuvant

an agent added to a drug to increase or aid its effect e.g. aluminum salt that helps stimulate a protective immune response -used in vaccines such as hep A, hep B, Tdap, DTaP, Haemophilus influenzae type b, and pneumococcal vaccines, but they are not used in the live, viral vaccines, such as MMR, varicella, and rotavirus. -aluminum hydroxide, aluminum phosphate, potassium aluminum sulfate ("alum") CpG-1018: oligonucleotide-based TLR-9 agonist (included in Heplisav-B®) MF59: lipid emulsion (part of Fluad®) AS01B: two-component mixture that includes monophosphoryl lipid A (MPL, part of Shingrix®)

Aspiration pneumonia causes

anaerobes like Peptostrepococcus, Peptococcus, Bacteroides fragilis and melaninogenicus, Fusobacteria

Entamoeba histolytica

anaerobic parasitic protozoa of human digestive tract, cold areas affected transmission: fecal-oral; no animal reservoirs cyst: survive for weeks in waters and soils and on foods under moist conditions, divides into 4 trophozoites in the small intestine, migrate to large intestine isolated from foreigners outside of the US, homosexual men, pts with HIV carried asymptomatically in the large intestines

zoonoses

animals to human e.g. cat-scratch disease, rabies, visceral or cutaneous larval migrans

Gonococcal Syndromes in Men and Women

anorectal-usually asymptomatic, irritation, painful defecation, constipation, scant rectal bleeding, painless mucopurulent discharge, tenesmus, and anal pruritis -anoscopic exam-mucosa may appear normal or purulent, erythema, or easily induced bleeding pharyngeal infection-mostly asymptomatic, pharyngitis, tonsilitis, fever, cervcal adenitis conjunctivitis-usually autoinoculation, eye irritation with purulent conjunctival exudate DGI (disseminated gonococcal infection)-systemic, infrequent, more common in women, produces bacteremia without urogenital sx, skin lesions, arthralgias, tenosynovitis, hepatitis, myocarditis, endocarditis, meningitis

*treatment regimes

anti-infective and antimicrobial drugs -antibacterial, antifungal, antiviral, antiparasitic -antibiotics is a common term for antimicrobials in general or specific for antibacterials

prophylactic therapy for infections

antibacterial chemotherapy for high risk patients (susceptible)-contacts, immunosuppressive therapy, cancer, having surgery

Kirby-Bauer Test

antibiotic disk diffusion test essential for groups of bacteria commonly showing resistance Biggest zone of inhibition does not necessarily mean it is the best antibiotic. There are other factors like size of the antibiotic, etc.

innate immune defenses

antigen non-specific methods to provide rapid, local response at the infectious site to restrict growth and spread of the organism-fever, antimicrobial peptides, interferon, complement, neutrophils, mast cells, basophils, eosinophils, macrophages, dendritic cells, NK cells

*How do influenza strains evolve?

antigenic drift and antigenic shift avian strains can evolve and infect humans

infection evading antibody-mediated immunity

antigenic variation-periodicaly altering epitopes-trypanosomes, Borrelia hiding within host cells-Plasmodium, Mycobacterium tuberculosis antigenic mimicry-coating with "self" proteins-Scistosoma, Plasmodium, HIV (gp120 and gp41) secrete enzymes to destroy Ab-H. influenzae (IgA), S. aureus (surface protein A immobilizes and destroys IgG), N. gonorrhea (IgA) receptor-mediated endocytosis-EBV (B lymphocytes), HIV (CD4 or T lymphocytes), influenza virus avoiding destruction by CD8 cytotoxic T lymphocytes-HSV1 (turns off protein coding genes), Cytomegavirus (disrupts MHC1 pathways and NK killing), EBV (proteins that mimic IL10 and inhibit Th1 cells)

ART

antiretroviral therapy-daily use to save lives but does not cure HIV reduces amount of HIV in the body, reduces transmission, reduces AIDS, and protects the immune system

Ophthalmia neonatorium

any eye infection in the first month of a baby's life cause: irritation, blocked tear duct, bacteria from birth canal -S. aureus from skin bacteria -Pseudomonas or Klebsiella from the mother's GI tract -gonorrhea, chlamydia, or HSV redness and swelling, discharge-may be watery or thick and pus-like for blocked tear duct use warm compression and gentle massage to unclog duct irritation will usually improve on its own in a few days abx ointment for bacteria without an STD

*antigen

any substance which can elicit in a host the formation of specific antibodies or the generation of a specific population of lymphocytes reactive with the substance

main sx of tuberculosis

appetite loss, fatigue, chest pain, coughing up blood or mucus, night sweats, pallor, weight loss, fever, GI sx

route of infection UTI

ascending: urethral colonization, reaches bladder or kidneys, infection descending (hematogenous): from distant primary source of infection, rare lymphatic: questionable

congenital Zika syndrome

associated with 5 types of birth defects rarely seen with other infections during pregnancy: severe microcephaly, decrease brain tissue with brain damage, damage to the back of the eye with a specific parrern of scarring and increased pigment, limited ROM (e.g. clubfoot), too much muscle tone restricting body movement soon after birth

Low-risk types (nononcogenic) HPV

associated with genital warts (6 and 11) and mild Pap test abnormalities recurrent respiratory papillomatosis associates with types 6 and 11

High-risk types (oncogenic) HPV

associated with mod-severe Pap test abnormalities, cervical dysplasia, cervical cancer, and other cancers HPV types 16 and 18 found in 70% of cervical cancers most with high-risk HPV infection never develop cellular changes or cancer

Catheterized Patients

asymptomatic bacteriuria and catheter <30d, remove catheter, no tx symptomatic bacteriuria and catheter < or >30d, remove catheter and treat

mechanisms of pathogenesis of Giardia

attachment of trophozoites to brush border-mechanical irritation or mucosal injury, villus structure affected lactase enzyme deficiency-reduces digestion and absorption of solutes leads to osmotic diarrhea and malabsorption syndromes

Mycoplasma pneumoniae

atypical pneumonia with no cell wall (sterol packed cell membrane) causes 20% of bacterial pneumonia in adults and is also the #1 cause of bronchitis in adults sx: gradual, mild, self-limited bronchitis and pneumonia, non-productive cough characterized by streaky and patchy infiltration of lungs (uni or bilateral) sx typically last 1 week but may be months most frequent in school-age children/young adults transmission-droplet and direct contact, moderately contagious smallest organism between viruses and typical bacteria incubation: 1-4w; communicability-20d diagnosis: culture barely used, serological assay PCR DOC-doxycycline or macrolide

Chlamydophila pneumoniae

atypical pneumonia, 10% of bacterial pneumonia in adults, #2 cause of bronchitis sx: gradual onset, mild, self-limited, non-productive cough; weeks to months characterized by streaky and patchy infiltration of lungs unilateral or bilateral

Dr. North Mycoplasma pneumoniae summary

atypical, no cell wall, resistant to many antibacterials, mimics the host cell mild, host functions normally diagnosis: culture barely used, serological assay PCR DOC-doxycycline or macrolide

ASD and vaccines

autism spectrum disorders The primary agent of concern here was thimerosol, a mercury-based preservative used in many (multi-dose) vaccines Thimerosol has been removed from most current vaccines The best current information that we have suggests that there is no known link between exposure to thimerosol and the risk or development of autism

MAP

average arterial pressure in one cardiac cycle

*bugs in complicated UTI

bacteria originate from bowel flora of host Acinetobacter, E. coli, Enterobacter, Enterococus, Klebsiella pneumoniae, P. aeruginosa, Proteus, Serratia, Staphylococci

*bugs in uncomplicated UTI

bacteria originate from bowel flora of host E. coli, S. saprophyticus, Klebsiella pneumoniae, Proteus, P. aeruginosa, Enterococcus

enterotoxins

bacterial exotoxins that produce N/V/D

GI infection

bacterial growth after ingestion and infection of live bacteria marked incubation period; Campylobacter, Salmonella, Shigella, cholera ulcers and helicobacter pylori

cellulitis

bacterial infection of skin and underlying tissues commonly in lower legs localized redness, pain, tenderness, warmth, and swelling RFs: *immunocompromised*, injury, lymphedema, obesity, IV drug use, skin condtions cause: GAS, S. aureus, H. influenza, and more tx: systemic abx targeting likely pathogens such as vanc+zosyn or vanc+perem

Infections through inhalation

bacterial pneumonia-Strep pneumonia, Legionella pneumophila meningitis and sepsis-N. meningitides, and H. influenzae TB viruses-measles, mumps, chickenpox, influenza, common cold

integrated concept of sepsis

bacterial products enter cell and induce production of cytokines/interleukins (IL1, 2, 6), TNF/cachectin, etc. neuroendocrine response releases epinephrine, glucagon, and steroids elevated blood sugar in critically ill patients

CNS Infectious Diseases

bacterial: meningitis, botulism, tetanus viral: meningitis, WNV mycotic: Cryptococcal meningitis protozoal: toxoplasmosis, PAM

homeostasis in sepsis

balance lost between proinflammatory (TNFalpha, IL1, IL6, IL8, PAF, leukotrienes, TXA2) and antiinflammatory (IL1RA, IL4, IL10) increase in coagulation and inflammation: proinflammatory mediators, endothelial injury, tissue factor expression, and thrombin production decrease in fibrinolysis: increased PAI1 and TAFIa reduced Protein C (activated Protein C inhibits PAI1

if you see any STIs in preadolescent children

be sure to rule out sexual abuse some are vertical transmission

BDQ

bedaquiline-first new TB drug in 40y *diarylquinolone (FQ)*-intended to be used in combo therapy in adults with pulmonary MDR TB inhibits the ATP synthase proton pump and to energy creation for the bacteria significant bactericidal and sterilizing in mice 400mg po qd for 2 weeks then 200mg po 3x weekly for a total of 24 weeks

*antibiotics that target bacterial cell wall

beta-lactams, glycopeptides (vancomycin), bacitracin Don't need to know for exam 1

bacteria reproduction

binary fission

classification of GI bacterial pathogens

biochemical: lactose fermenters (dye changes color with change in pH), H2S producers (hydrolyze urea, liquefy gelatin, decarboxylate amino acids) surface antigens: O (LPS-most *O*utermost, gram -), K (*K*apsule) that covers O antigens, H (subunits of flagella-*H*urry antigen)

HPV vaccines

bivalent: HPV16 and 18 (cervical precancers); quadrivalent: HPV6, 11, 16, and 18 (cervical, vulvar, vaginal and anal precancers; genital warts)

Blastomyces dermatiditis

blastomycosis, dimorphic mycosis Skin and bone Later nervous system and visceral organs DOC: amphotericin B, itraconazole Skin lesions resulting from the dissemination of the fungus from the lungs - Soil fungus (=> spores inhaled) - S-SE USA - Predominantly in lung and skin Clinical Symptoms: route of infection is inhalation of conidia Pulmonary blastomycosis may be asymptomatic or present a mild flulike illness. more severe infection resembles bacterial pneumonia with acute onset, high fever, lobar infiltrates, and cough. *Un*common amongst people with AIDS or immunocompromising conditions. Tissue sections showing large, broad-base, unipolar budding yeast-like cells Tissue sections showing large, broad-base, unipolar budding yeast-like cells Broad based budding and thickened cell walls and globose shape are characteristic of the yeast form of Blastomyces dermatitidis Differential interference contrast microscopy, potato glucose agar, 25° C Differential interference contrast microscopy, 37° C

BBB

blood brain barrier-created by tightly joined capillary endothelial cells Drug entry into brain tissue: direct passage through capillary endothelial cells

giemsa stain

blood smear for CBC differential, blood-borne parasites, fecal leukocytes

*BCSFB

blood-CSF barrier that ia created by ependymal cells of choroid plexus controls passage of drugs into CSF active transport system-inhibited during the inflammation from meningitis

dysentery

bloody diarrhea mechanism: infection inflammatory invasion or cytotoxin colon or distal small bowel Shigella, Salmonella (nontyphi), C. jejuni, EHEC, C. difficile

botulism tx

botulinum antitoxin (BAT)-heptavalent equine (ABCDEFG) BabyBIG-botulism immune globulin IV

BSE

bovine spongiform encephalopathy sx: nervous and violent cows with trouble walking thought to be linked to feeding cow meat-and-bone from sheep infected with scrapie (another prion disorder) 1993-2014-184500 bovine cases, but only 2 in 2015 (declining)

*ebola risk assessment-low

brief contact (e.g. shaking hands) with a symptomatic pt with no PPE direct contact with a symptomatic pt with appropriate PPE lab processing with appropriate PPE country with widespread disease and control measures

PID treatment

broad spectrum antibiotics

Yersinia pestis clinical presentation

buboes-swollen armpit/groin/neck lymph nodes hemorrhagic purple spots septicemic plague-lethal spread to bloodstream pneumonic plague-bacteria localizes in lungs highly infectious, mortality >90%, shock and death within 48h

BEPSEUDO

burns, endocarditis, pneumonia, sepsis, external malignant OM, UTI, diabetic osteomyelitis

+ RNA

can be made straight into proteins by taking over the host cell's machinery

tuberculosis

can live incide cell, may be part of normal flora in other countries in the form of respiratory droplet that will only cause disease in the immunocompromised leading cause of death by single disease causing organism-public health emergency since 1993, 20-40% of the world is latently infected 10% of immunocompetent individuals in their LIFETIME 8% of immunocompromised individuals PER YEAR (30x increase) RF: HIV (13% of all TB cases), MDR, and deterioration of public health infrastructure for TB control LTBI and TB disease in people born in endemic areas: Asia, Africa, Russia, Eastern Europe, Latin America

factors affecting BCG vaccine

can subvert monocyte differentiation and affect antigen presentation primed Tcells inability to produce IFN-gamma induces dermal hypersensitivity to purified protein derivative (PPD) tuberculin live bacteria-not recommended in HIV pts local injection site abscesses *booster administration of live vaccines considered a waste of time* COLD CHAIN SYSTEM is complex, expensive, and not very effective

lobomycosis dx

cannot be cultured, direct exam of biopsy-crushed KOH wet mount reveals spheroid yeast 5-12 microns, thick-walled and multinucleate, form chain with cells joined by bridges

*Obligate parasites

cannot survive without host entirely or in some stage of its life cycle

How is adenovirus prevented and treated?

careful handwashing and chlorination of swimming pools DOC-cidofovir and ribavirin used to treat immunosuppressed people

Screening for MRSA colonization

carrier-colonized in nose, sputum, urine, wound, stool, or skin without disease elimination of carriers through use of infection control measures and/or antibiotics which will decreases the risk of transmission to high-risk individuals 1st line IV: vancomycin; 1st line oral: Bactrim

Select Gram Positive Cocci Tests

catalase-differentiates staph (+) from strep (-) -catalyzes conversion of hydrogen peroxide to oxygen and water coagulase-differentiates S. aureus from other Staph Optochin (chemical)-S. pneumo is sensitive, S. viridans is not Bacitracin-GAS is sensitive, GBS is not Novobiocin-S. epi is sensitive, S. sapro is not

Cytotoxin

cause destruction of mucosal cells and associated with inflammatory diarrhea -Shigella, Shiga-like toxin or verotoxin or Enterohemolytic (hemorrhagic) E. coli (EHEC)

Acanthamoeba and Naegleria

cause rare and usually fatal brain infections, commonly found in water Acanthamoeba-cuts, conjunctiva (keratitis), inhalation, amebic encephalitis Naegleria-swimmers inhale contaminated water -Amebic meningoencephalitis when trophozoites migrate to the brain prevention is difficult because these organisms are environmentally hardy

Enterotoxins

cause watery diarrhea by acting directly on secretory mechanisms in the intestinal mucosa e.g. S aureus, V. cholera, Enterotoxigenic E.Coli (ETEC), C. perfringens

aspergillosis

cause: Aspergillus fumigatus (most common) aflatoxin-mycotoxin that can cause liver damage and liver cancer three manifestations: 1. allergic bronchopulmonary aspergillosis (ABPA)-IgE mediated allergic reaction to spores 2. aspergilloma-large fungal ball in lung cavities from previous TB or cancer that must be surgically removed 3. invasive aspergillosis-limited to immunocompromised patients especially transplant, end-stage AIDS, and the severely neutropenic (post-chemo)

Louse-borne borreliosis = Epidemic Relapsing Fever

cause: Borrelia recurrentis spread by body louse Only infect host when louse is injured so a single louse can only infect a single person. Louse leave the host with a fever and seek a new host.

candidiasis

cause: Candida albicans dx: KOH skin scrapings, stains, cultures, blood test for beta-D-glucan (component of fungal cell walls), T2Candida-PCR assay for DNA normal flora-often cultured from urine, sputum, and stool should NEVER be isolated from blood samples

mucormycosis

cause: Rhizopus, Rhizomucor, and Mucor aggressively invade sinuses, cranial bones, and blood vessels in at-risk population e.g. DM, severely immunocompromised, burn victims, deferoxamine-iron chelator

sporotrichosis

cause: Sporothrix schenckii; yeast at > 37C; hyphae at < 25C (dimorphism) most common in USA found in plants, soil, Chorns, and timber spreads from primary site to the regional lymph nodes pyogranulomatous reaction-nodules on the skin, subcutaneous tissue and in the lymph nodes which later soften and ulcerate

Syphilis

cause: Treponema pallidum, corkscrew, motile, microaerophilic cannot be cultured in vitro or viewed by normal light microscopy may become chronic without treatment most contagious sexually during primary and secondary stages rapid decline in the 1940s because of penicillin -still DOC with 2.4 million units IM single dose all cases must be reported to local health department

Eumycetoma

cause: hyaline and phazoid hymphomycetes usually single, with well-defined margins late in sinuses and less in number -flat opening that is not easily removed -serous or sero-sanguineous discharge black or white grains less extensive, only osteosclerotic lesions of bone

Coxsackieviruses A and B

caused by picornaviridae, nonpolio enterovirus (less virulent than polio) echovirus-Enteric Cytopathic Human Orphan causes: respiratory infections, conjunctivitis, hand-foot-mouth disease rare cases of coxsackievirus and echovirus paralysis, aseptic meningitis and encephalitis A-vesicular lesions; B-body myocarditis and pleurodynemia

*epidemiology diarrhea

causes >50% of childhood deaths in developing nations In US: 76 million cases; 350,000 hospitalizations; 5,000 deaths bacterial pathogens in 6% of cases , Campylobacter most common fecal leukocyte absence in viral infections and intoxication

CORONA

causes SARS, large-spiked enveloped virus, common in pigs, cats, dogs, poultry

cryptococcosis

causes: Cryptococcus neoformans and C. gattii polysaccharide encapsulated yeast that is inhaled most commonly found in pigeon droppings major manifestation-meningoencephalitis 75% occur in immunocompromised pts (10% of AIDS pts) dx: india ink stain of CSF (positive 50% of the time), cryptococcal antigen test

systemic mycosis

causes: Histoplasma capsulatum, Blastomyces dermatitidis, Coccidioides immitis Mostly originating in the lung caused by virulent dimorphic fungi Infections are rare (high natural immunity) Usually requires large inoculum Often endemic to specific areas endemic to Arkansas: histoplasma, blastomycosis

gonorrhea treatment

ceftriaxone 250mg IM plus azithromycin 1g single dose (usually with chlamydia)

fungal morphology

cell membrane-contains ergosterol (target of most antifungals) cell wall-mostly carbohydrates, protect against human immune system capsule-polysaccharide coating found in Cryptococcus neoformans

CSF

cerebrospinal fluid-produced by ventricles in the brain that flows downward through the spinal cord and is removed by the arachnoid villi and vertebral venus plexus located in the spinal cord 40-60mL in infants; 60-100 in children; 115-160 in adults

C. trachomatis Infections in Women

cervicitis-most asymptomatiic, mucopurulent endocervical discharge and edematous cervix (with erythema and friability) urethritis-usually asymptomatic, dysuria, frequency, "sterile" pyurias complications: PID (endometritis, salpingitis, tubo-ovarian abscess, peritonitis), perihepatitis (Fitz-Hugh-Curtis Syndrome), reactive arthritis

pleurodynia

chest pain or abdominal pain, commonly associated with fever, malaise, and HA

amebic liver access

chocolate-colored "pus", necrotic material, usually bacterial free, lesions expand and coalesce, further metastasis direct extension or fistula

*infectious diarrhea from toxins

choleragen toxin E. coli heat labile toxin (LT) similar in structure to choleragen-E. coli, Campylobacter jejuni, and Bacillus E. coli heat stabile toxin (ST)-E. coli, Yersinia enterocolitica Shiga-like toxin-Shigella dysenteriae, enterohemorrhagic/invasive E. coli

*exceptions to normal course of infections

chronic infections, subclinical or subacute illness, insidious disease, fulminant illness

CWD

chronic wasting disease-affects deer, elk, and moose to cause sx of weight loss, excessive salivation and urination, blank facial expression, grinding of teeth, and repetitive walking in set patterns

genital HSV

chronic, lifelong viral infection, mostly HSV2 most transmitted by asymptomatic shedding; men transfer more than women increases the risk of HIV 2-fold; facilitates transmission of HIV as well herpetoviridae family, latent infection in specific target cells, recurrent

mycetoma

chronic, slowly progressive granulomatous infection of the skin and subcutaneous tissues with possible involvement of underlying fascia and bones - commonly affects the extremities, multiple sinuses discharging viscid, seropurulent fluid containing granules or grains which are microcolonies of the causative agent maduramycosis AKA madura foot-(sub)tropical by eumycetoma fungi and actinomycetes bacteria found in the soil bacterial-white to yellow grains (except Actinomadura pelletieri-red) fungal-black and white grains young men 20-40yo, field workers prone to thorn prick and trauma eumycetoma (40%) and actinomycetoma (60%) ear-from wicks to remove earwax; back, head, and neck-carrying goods triad of clinical features-tumefaction (tumor-like swelling), multiple draining sinuses, granules in sinuses (NO LIQUIFACTION) DOC for eumycetoma - PO ketoconazole & and itraconazole DOC Madurella and Fusarium - amphotericin B

bacterial meningitis

classic triad: nuchal rigidity, fever, AMS additional sx: severe HA, chills, photophobia, drowsiness, seizures young children: bulging fontanelle (soft spot), apnea, purpuric rash, convulsions

Specimen collecion tips for blood cultures

clean with betadine/chlorhexidine (ETOH doesn't kill as many bacteria and the bacteria are more likely to be resistant collect from 2 different sites for both confirmation and to eliminate contamination collect before starting antibiotics never draw from ports/lines, rather draw distal to line/port (avoid contamination)

normal CSF components

clear, protein <50, glucose 50-60% of peripheral serum glucose, pH 7.4, WBC <5 (lymphocytes)

ebola risk assessment-moderate

close contact with someone with ebola without appropriate PPE (within 3 feet for a prolonged period of time) in countries with widespread transmission direct contact or body fluids with appropriate PPE (anyone involved in patient care)

opsonization

coating antigen with antibody which enhances phagocytosis

*shape and arrangement

cocci (kokkos-Greek for berry)-spherical or oval, 0.5-1 mcm diameter, diplo (pair), strepto (chain), staphylo (cluster) bacilli (rod)-slender, short/plump (coccobacillus), club-shaped, 0.5-20 mcm long, single (Clostridium) or chains (Bacillus) spiral-three forms-vibrio (comma), spirochete (thin walled helical without flagella like Leptospira and Borrelia), spirilla (thick walled helical with flagella like Spirillium and Campylobacter)

How is Acinetobacter different from other UTI-causing agents?

coccobacilli, obligate aerobe

Symptomatology of infections

collection of sx of the host during disease AKA clinical picture or presentation sx differ based on the infectious agent, interaction between invading organisms, and retaliation of the host (inflammation, immune system) types: specific vs. nonspecific and overt vs. covert

colonization vs infection

colonization-growth infection-growth AND causing damage (sometimes just overgrowth)

prevention of vertical transmission of HIV

combo ARV regimens regardless of virologic, immunologic, or clinical parameters

Vibrio cholera

comma, GNR with single polar flagellum, facultative anaerobe and pathogen reservoir: asymptomatic human carriers transmission-contaminated food and water, estuarine shell fish LPS A (endotoxin), core polysaccharide, O antigen 200+ serotypes, but only 2 (01 and 0139) are associated with epidemic and pandemic cholera pathogenesis related to acquisition of the VPI (vibrio pathogenicity island) and bacterial ophage (CTXtheta)-transmitted laterally between strains acute, severe, voluminous watery diarrhea (rice water stool- up to 1L/h), vomiting, and dehydration no tenesmus, strain, abdominal pain, or fever duration: 1-3 days; rehydration IV followed by Oral Rehydration Solution (glucose and electrolytes; DOC-doxycycline

Staph epidermis

common HAI, covers 90% of outer skin surface, infected cuts and UTIs

shingles

common painful skin rash inervated by an infected neuron *reactivation* of VZV (varicella zoster virax)-usually only effects one dermatome tx: acyclovir, valacyclovir, topical and/or systemic pain relief ZOSTAVAX and SHINGRIX recommended 60+yo (labeled for 50+yo) you can have shingles without ever having chicken pox, because the virus may have never manifested with symptoms

Fasciolopsis buski

common parasite of humans and pigs in SE Asia one of the largest trematodes to infect man (8cm), upper intestine chronic infection: inflammation, ulceration, haemorrhage of the small intestine

Erysipelas

common, bacterial skin infection of upper dermis-red face, arms, or legs can distinguish from cellulitis because of the clear demarcation cause-S. pyogenes; tx-oral penicillin VK

Taenia saginata

common, mild, worldwide tapeworm acquired by ingestion of uncooked beef

CAP

community acquired pneumonia- S. pneumoniae, H. influenzae, atypicals (Legionella pneumophila, Mycoplasma pneumoniae, Chlamydia pneumoniae)

RETRO viridae

complex (symmetry), + stranded RNA reverse transcribed into DNA e.g. HIV

POX viridae

complex (symmetry), enveloped, DNA virus e.g. smallpox

helminths

complex life cycle: 1. infective stage-egg or larva 2. intermediate hosts-may be more than one, no adults 3. definitive host-adult nematodes-roundworms; platyhelminthes-flatworms; trematodes-nonsegmented flukes; cestodes-segmented tapeworms

*CNS anatomy

components: brain, meninges, spinal cord, CSF axenic environment-no normal microbiota pathogens access via break in bones or meninges, spinal tap, axonal transport

genital warts

condylomata acuminata (cauliflower-like appearance, skin-colored, pink, or hyperpigmented, may be keratotic on skin but generally nonkeratinized on mucosal surfaces), smooth papules, flat papules, keratotic warts (thick horny layer that can resemble common warts or seborrheic keratosis) most commonly occur in areas of coital friction perianal warts do not necessarily imply anal intercourse as it may be secondary to autoinoculation, sexual activity other than intercourse, or spread from nearby genital wart site HPV types causing genital warts can occasionally cause lesions on oral, upper respiratory, upper GI, and ocular locations. Genital warts-usually asymptomatic, vulvar warts (dyspareunia, pruritis, burning discomfort), penile warts (occasional itching), urethral meatal warts (hematuria or impairment of urinary stream), vaginal warts (discharge/bleeding, obstruction of birth canal secondary to increased wart growth during pregnancy), and perianal and intra-anal warts (pain, bleeding on defecation, itching) spontaneous regression estimated at 10-30% within 3mo recurrences after treatment are common.

vertical transmission

congenital infections from mother to child either across the placenta or through infected vaginal secretions of the mother during birth e.g. HIV and TORCH infections (Toxo, Other (Varicella, strep B, syphilis), Rubella, Cytomegavirus, Herpes)

congenital vs. perinatal

congenital: mother to child during gestation perinatal: mother to child during birth

biomolecules combination in vaccines

conjugates, acellular, polysaccharide (protein conjugates such as those in Prevnar 13 used to prevent Strep pneumo

smallpox

contagious, disfiguring, and often deadly viral disease cause: orthopoxvirus (*Variola Virus*-dsDNA) prodromal period includes high fever, body aches, and malaise rash begins on the face and spreads downward over the whole body rash becomes pustules and finally crusts, leaving scarring. virus was declared eradicated by the WHO in 1980 antiviral medications exist in case of virus re-emergence. enough vaccine exists to vaccinate everyone in the US should an outbreak occur Portal of entry = inhaled

*non-sterile body sites

contain normal flora-mouth, nose, URT, skin, GIT, urethra

convalescent period of infection

containment of infection and progressive elimination of the pathogen resolution of sx and repair of damaged tissue over days, weeks, or months

pyrazinamide for TB

converted to active pyrazinoic acid in acidic conditions of macrophage lysosymes and is bacteriostatic to susceptible strains and may be bactericidal against actively dividing organisms

What virus is responsible for causing SARS?

coronavirus

HIV pre-exposure prophylaxis

counseling and behavioral interventions for those with HIV can reduce secondary transmission of HIV tenofovir/emtricitabine (Truvada) to reduce risk of HIV infection in uninfected high-risk individuals

C&S

culture and sensitivity-gold stadard of microbiology minimum of 18h, but usually 48h relatively unculturable bacteria-chlamydia, syphilis, leprosy note: positive cultures are generally more meaningful than negative caveat-negative may be false negative, positive may be contaminant

Gonorrhea diagnosis

culture or NAAT

direct tests for TB

culture, direct smear microscopy, molecular techniques, antigen and lipid detection, animal pathogenicity testing

GIT and Visceral Infection

cuts or injection in mucoepithelial membrane, primarily mouth barriers to invasion: mucus, ciliated epithelium, stomach acid, bile, IgA (mucosal) Two stages: 1. primary-bloodstream and lymphatic system in microfold cells in Peyer's patches and mononuclear phagocytes and lymphocytes 2. secondary-amplification of infection by replication in phagocytes, endothelia or liver, as well as, infection of target tissues

Bacterial Internal Assets

cytoplasm-nucleoid, plasmids, ribosomes, enzymes, nutrients nucleoid-naked, circular molecule of DNA plasmid-additional hereditary material ribosomes-70S (50+30), humans are 80S (60+40)

shiga toxin

cytotoxin produced by Shigella dysenteriae B subunit binds to host cell glycolipid Gb3 and facilitates transfer of A subunit A subunit disrupts protein synthesis by preventing binding of aminoacyl-tRNA to the 60S ribosomal subunit which results in destruction of intestinal cells and villi and decreases intestinal absorption

Clostridium difficile treatment

d/c implicated abx metronidazole or vanc (glycopeptide) necessary for severe diarrhea or colitis fidaxomacin superior to vanc in recurrent infection vanc is given orally for pseudomembranous colitis, but not pneumonia because vanc isn't absorbed orally and cruises down the gut to kill C. diff in the GIT

GIT Disease

damage the epithelial lining, alter fx of the lining and absorptive villi, cause malabsorption of water and electrolyte imbalance, gastroenteritis, diarrhea and vomiting, more in infants (rotaviruses), poor hygiene (fecal-oral transmission)

*high risk environments for infection

daycare, nursing home, prison

host cell outcome with virus

death-host cell function shuts down transformation-activates or introduces oncogenes which results in uncontrolled and uninhibited cell growth e.g. HPV latent infection-virus survives inside the host cell in an inactive state, but can reactivate in the right conditions e.g. shingles, herpes (cold sores when sick) chronic slow infection-cause disease after years (often decades) of indolent infection e.g. HIV

*Clostridium perfringens treatment

debridement, high dose PCN (no abx for food poisoning), hyperbaric oxygen

botulinism toxin

decreases the release of NT from cholinergic neurons causing flaccid paralysis

tetanus toxin

decreases the release of NT from inhibitory neurons to produce spastic paralysis AKA tetanospasmin-transported from NMJ to CNS where it acts on inhibitory Renshaw cell interneurons to prevent GABA and glycine NT release. Failure of inhibition leads to unregulated excitation of motor neurons hyperreflexia, muscular spasms, risus sardonicus (lockjaw)-grotesque sardonic grinning expression, cardiac arrhythmia, fluctuation in BP and sweating

cutaneous mycosis

deeper layers of epidermis and its integuments, hair and nails scrapings seen with Gomori methenamine silver and Periodic acid Schiff (special stains for fungi) and KOH dermatophytes are morphologically similar and appear as hyaline septate hyphae that invade the stratum corneum, hair follicles, and hairs

What has been another recent use for adenovirus?

delivery of genetic material as a part of gene therapy

most potent APC

dendritic cell

DHF

dengue hemorrhagic fever-lasts 2-7d, abdominal pain, nausea, severe myalgia "break bone fever", AMS and early signs of shock (irritable, confused, cold skin, increased puls, altered consciousness), hemorrhagic sx (can be fatal) dx: serology (IgM?), RT-PCR

HPV complications

depressed or hypertrophic scars uncommon, but can occur especially if the pt has had insufficient time to heal between txs rarely can result in disabling chronic pain syndromes e.g. vulvodynia or hyperesthesia or treatment site pts should be notified that persistent hypopigmentation or hyperpigmentation are common with some txs

KOH prep

dermatophytes (fungi) + KOH dissolves keratin

Management of Septic Patients

detailed initial assessment-HR, BP, O2, RR, T, UO A-airway, B-breathing, C-circulation

HIV post-exposure prophylaxis (PEP)

determined by level of risk; tx ideally initiated within 1-2h of exposure, but recommended up to 72h; optimal duration at least 4 weeks

diagnosis and tx of Norovirus

difficult to culture, mostly PCR (real time quantitative reverse transcriptase PCR), Ab testing by ELISA (low sensitivity and specificity) supportive fluid replacement therapy bismuth subsalicylate for stomach discomfort

histoplasmosis

dimorphic fungi, endemic to AR, causes respiratory illness, saprote hyphae in nature, creates spores, released into air, forms yeast when breathed into the lungs which creates endospores which are released when the cell lyses where it can either infect more cells or get breathed out where it can grow on the ground and start over

Histoplasma capsulatum

dimorphic mycoses, acute pneumonia (cave disease), chronic pneumonia (smoker), disseminated (immunocompromised), primary cutaneous (lab accidents) DOC: amphotericin B; viewed with PAS stain starlings were brought to NYC in 1890 by a Shakespeare fan and the Histoplasmosis followed in their droppings whose spores can be inhaled S-SE USA (Ohio and Mississippi Valley) starts with flu-like sx meningitis, 95% asymptomatic, chronic infection can lead to lung fibrosis, multiorgan failure and sepsis in the immunocompromised fungus lives intracellular in macrophages (immune evasion)

Coccidiodes immitis

dimorphic, skin, bones, joints, subcutaneous tissues, visceral organs DOC: amphotericin B soil fungus whose spores can be inhaled-SW US and Mexico "Valley fever" sx: starts with flu-like sx, meningitis, coccidioidal granuloma and San Joaquin fever Filipino>AA>Hispanics>Asians>Caucasians "great imitator"-wide variety of lesions like syphilis and TB tissue section showing typical endosporulating spherules typical single-celled, hyaline, rectangular to barrel-shaped, alternative arthroconidia

Molecular Technique for TB

direct detection from specimen via PCR and target amplification identification from culture via PCR sequencing, DNA and gene probes antigen detection via ELISA

ebola virus pathogenesis

direct infection of tissues, immune dysregulation, hypovolemia, vascular collapse, multi-organ failure, septic shock, DIC (disseminated intravascular coagulation)

*contagious

direct transmission from infected tissues or secretions e.g. handshakes, sex, kissing, bites, etc.

*microscopy types

direct wet mount (wet prep or KOH prep) stain (gram, giemsa, trichrome, acid fast, india ink) shape and arrangement

penetration

disruption in the integrity of a body's surface barrier e.g. abrasions, burns, wounds, surgery, catheterization, intraveous drug use, animal/arthropod bites primary infectious process produces surface lesions e.g. chicken pox or impetigo dangerous form of penetration-large number of organisms bypass the host's primary immune defense systems Direct inoculation from intravenous drug use or from animals/arthropod bites - Dangerous form of penetration: -Large numbers of organisms can gain access directly into vital sites -Bypassing the host's primary immune defense systems.

systemic pathogen

disseminates from the site of primary infection to other locations (usually via circulatory system) e.g. N. meningitides, Salmonella typhi (typhoid fever), Borrelia burgdorgeri (Lyme disease)

diderm

double cell membranes

Tips for UTI Prevention

drink plenty of water, take showers, avoid prolonged baths, wipe from front to back after using the bathroom, do not "hold it", do not wear tight-fitting undergarments made of nonbreathing materials, *void after intercourse for women,* avoid spermicidal jelly

Haiti and poop use

dry compost toilets whose contents are then processed and used as fertilizer

gangrene

dry gangrene-slow spread, shrunken, black dead tissue-often low blood supply wet gangrene-fast spread, swollen, black, under tension-impeded venous return gas gangrene-typically associated with trauma, spores infect skin (cellulitis), dissolve cell membranes and produce H2S (hyperbarics to kill anaerobic bacteria and neutralize H2S smell)

tetanus dx and tx

dx based on symptoms and history, no lab test confirmation medical emergency human tetanus immunoglobulin (TIG)-injection/infiltration for wound (also IM) agents to control spasms: antibiotics, immunization

cryptococcal meningitis dx and tx

dx: based on CSF, india ink staining, fungal culture, cryptococcal Ag tx: antifungal agents like amphotericin B +/- flucytosine followed by long-term flucoazole for suppression

Symptomatic Abacteriuria or Acute Urethral Syndrome

dysuria and pyuria (females), <100,000 CFU/mL most have infection and require tx if do not respond to tx, consider cx and possible STD

clinical presentation lower UTI

dysuria, urgency, frequency, nocturia, suprapubic heaviness, gross hematuria (elderly pts are exception) UA: bacteriuria, pyuria, possible nitrite-positive, leukocyte esterase-positive

prevention of swimmer's ear

eat plugs when around water, hair dryer to dry ears, ear solution with 2/3 rubbing alcohol and 1/3 vinegar

enterovirus tx and prevention

effective Ab protective immunity tx: pleconaril inhibits penetration of virus into cells early in the course of infection vaccines (live and attenuated) elicit IgA and IgG, stops viral spread to and from gut and in the body, live vaccine is shed in feces and spread to contact-immunize contacts

Unique Viral Characteristics

energy-less, composed of a capsid that surrounds genetic material genetic material is either DNA or RNA (NEVER both) replication occurs when the virus takes control of host cell machinery

gram + microaerophilic

enterococcus and streptococcus (some are facultative anaerobes)

Clostridium difficile toxins

enterotoxin A-cytopathic effect-disruption of tight cell-to-cell junction -increases permeability of intestinal wall and diarrhea -acts as inflammatory mediators-chemotactic factor for neutrophils and release of cytokines cytotoxin B-destroys intestinal and tissue cell

Coxsackie virus

enterovirus, picornaviridae family "24h" diarrhea, myocarditis, aseptic meningitis, and may trigger insulin-dep DM

Poliovirus

enterovirus, picornaviridae family, infect skeletal muscle to gain access to brain cytolytic for motor neurons of the anterior horn and brain stem-cause paralysis

Flaviviruses

enveloped ssRNA, most arboviruses (arthropod-born e.g. Aedes mosquitos) Abs enhance infectivity and promote viral uptake into macrophages, monocytes, and other cells (opsonization)

ESR

erythrocyte sedimentation rate high ESR indicates serious infection

pathogenesis of normal flora

especially common in immunocompromised individuals Common examples in immunocompetent individuals include: -Dental caries -Periodontal disease -Abscesses -Foul-smelling discharges -Endocarditis (Less common)

endemic zoonotic H5N1

especially tenacious Despite the death or destruction of an estimated 150 million birds, the virus is now considered endemic in many parts of Indonesia and Viet Nam and in some parts of Cambodia, China, Thailand, and possibly also the Lao People's Democratic Republic. Control of the disease in poultry is expected to take several years. A strong link between duck grazing patterns and rice cropping intensity in H5N1 highly pathogenic avian influenza in Thailand and Viet Nam. Ducks feed mainly on leftover rice grains in harvested paddy fields, so free-ranging ducks in both countries are moved to many different sites in line with rice harvest patterns. Virus persistence is now increasingly confined to areas with intensive rice-duck agriculture in eastern and southeastern Asia. 90 % of the world's 1.044 billion domestic ducks are in Asia China and Viet Nam account for the bulk of this - 775 million or 75 percent. Thailand has about 11 million ducks.

EPO

euedaphic pathogenic organisms-true soil organisms-includes most bacterial and fungal pathogens-facultative/opportunistic pathogens e.g. Actinomycetoma, anthrax, botulism, Campylobacteriosis, Leptospira interrogans, Listeria, tetanus, Francisell tularensis, gas gangrene, Yersinia enterocolitica

mosquitoes and disease transmission

every temperature zone including the artic; larvae overwinter in temperate zones 3500 species-small fraction vector disease to human chief genera: Anopheles (malaria, filariasis), Aedes (YF, dengue, chikungunya), Culex (WNV, Japanese encephalitis, filariasis) most are distinct selective feeders-ammals, birds, reptiles

Bacillus anthracis

excessive inflammation may progress to fluid build up in the lungs anthrax toxin: edema factor (EF), lethal factor (LF), protective antigen (PA)

H5N1 exposure risk

exposure risk highest during slaughter, defeathering, and cooking preparations no evidence that properly cooked poultry can be a source of infection currently no efficient human-to-human transmission of the virus avoid live or "wet" poultry markets, farms, etc. where diseased birds may be

ESBL

extended spectrum beta-lactamase E. coli and Klebsiella can develop this resistance mechanism and make them no longer susceptible to cephalosporins. Use carbapenem instead. Now some Klebsiella is resistant to carbapenem as well

*exogenous

external environment such as water, food, soil, or air

dengue hemorrhagic virus

family: flaviviridae, genus: flavivirus, only arbovirus adapted to himan host eliminated other reservoirs-no maintenance in primitive enzootic forest cycle most widespread arbovirus, (sub)tropical leading cause of hospitalization and death (>90%) in children <15yo in SE Asia resurgence of epidemic dengue fever in 2000s in the Americas DHF emergence for the first time in the past 20 years

hookworm dx

fecal smears containing eggs measure Hb, serum ferritin, iron to exclude other causes of anemia

cryptosporidium parvum

fecal-oral intestinal coccida that can be systemic in AIDS (can be fatal) originally considered an animal parasite (rodents, cattle, sheep), some (fish, fowl, reptiles) do not infect humans oocysts are 2-5 microns in diameter, do not stain with iodine, acid-fast can be sexually transmitted, resistance to disinfectants most infections cause severe diarrhea DOC: nitazoxanide

echovirus 11 transmission

fecal-oral route

transmission on intestinal protozoa

fecal-oral route, cyst and then trophozoite stage

prevention and control of Entamoeba histolytica

fecal-oral transmission so reducing contamination is needed in endemic areas filter and purify drinking water with iodine or boiling, wash fruits and vegetables grown in nightsoil, improved sanitation, drink bottled water, and don't use ice

clinical manifestations in West African ebola outbreak

fever, fatigue, arthralgia, myalgia, HA, confusion, eye pain, coma, chest pain, cough, dyspnea, sore throat, hiccups, vomiting, diarrhea, anorexia, abdominal pain, dysphagia, jaundice, unexplained bleeding (melena, gingival, hematuria, ecchymoses, etc.), conjunctivitis, rash

chickenpox

fever, itchy blisters on back and trunk and spreads to face and extremities cause: varicella-zoster virus (dsDNA), typically inhaled tx: supportive therapy and acyclovir in the immunocompromised vaccine given at 12-15mo and a booster at 4-6y

*What are potential adverse effects of the flu vaccine?

fever, muscle aches, malaise

mumps

fever, swelling of salivary (parotid) glands, orchitis ELISA for diagnosis; humans are the exclusive natural reservoir DOC-hyperimmune serum IgG to prevent orchitis and prevent sterility in adults transmission-salivary and respiratory secretions; incubation: 2-3w those infected can recover with permanent immunity.

Streptomycin for TB

first drug used clinically but is now secondline due to its toxicity aminoglycoside, protein synthesis inhibitor, decreases fidelity of mRNA and garbles the message which leads to nonsense proteins AE: cranian nerve 8 affected-auditory and vestibular function

Rifabutin for TB

firstline, rifampin derivative (less potent), less interactions with HIV medications similar AE to rifampin-most common GI intolerance, skin rash, and neutropenia

Rifampin for TB

firstline-inhibits DNA dep RNA polymerase-bactericidal and broad spectrum resistance: structural alteration of DNA dep RNA polymerase prevents further initiation but not elongation, drug ineffective against altered enzyme

Rifapentine for TB

firstline-long-acting rifamycin that can be used once weekly in the continuous phase of tx in carefully selected HIV-negative pts 85% as potent an enzyme inducer as rifampin, likely with similar DDIs

Trichomonas vaginalis

flagellate protozoa, common STD, world-wide, infects male (urethra, prostate, epididymis) and females (vagina)

Giardiasis

flagellated protozoan, G. lamblia (G. duodenalis, G. intestinalis), worldwide, most common protozoan isolated from human stools typically noninvasive and asymtomatic, acute/chronic diarrhea ingested cyst and excystation takes place in the duodenum exposure of cysts to acidic pH or other sources of hydrogen ions acts as an environmental cue for the parasite, trophozoites emerge through a break in the cyst wall (mediated by proteases) and flagellar activity will begin 5-10min later trophozoite-undergoes cytokinesis (cell division without nuclear division), pear or tear-drop shape, bilateral symmetry

clinical presentation upper UTI

flank pain, fever, N/V malaise PE: costovertebral tenderness UA: same as lower UTI + Ab-coated bacteria

platyhelminthes

flat worms, no body cavity, alimentary canal with blind ending if present

arboviruses

flavi, toga, bunya, rhabdo, reo, orthomyco viral families arthropod-born, compex life cycle limits transmission requires endemic specific reservoirs and amplifying hosts

chromoblastomycosis tx and prophylaxis

flucytosine common, itraconazole, fluconazole, terbinafine responds poorly to available therapies, relapses frequent cryotherapy, thermotherapy, laser therapy, chemo, surgery

*antibiotics that target DNA gyrase in bacteria

fluoroquinolones (Cipro) Don't need to know for exam 1

*FQ

fluroquinolone

Transmission of Select Bacterial Pathogens

foodborne: EHEC, Salmonella, Vibrio, Campylobacter, Shigella, C. perfringens, B. cereus, Yersinia enterocolitica animal reservoir: Salmonella, Campylobacter, C. perfringens, Yersinia enterocolitica, and E. coli(?) waterborne: ETEC, Salmonella, Campylobacter, Vibrio cholerae

hepatitis A vaccine

for children at 1yo, travelers to regions with mod-high rates, MSM, certain illegal drug users, people with clotting-factor disorders, people who work with HAV, people with chronic liver disease, and anyone else seeking long-term immunity HAVRIX or VAQTA (preservative free)-both inactivated, 2 injections 6 mo apart postvaccination measurement of Ab response is not required Twinrix-Hep A and B for pts >18yo, 3 doses (0, 1, and 6mo)

post-exposure prophylaxis of hepatitis A

for unvaccinated persons recently exposed -if healthy and 1-40yo give single antigen vaccine -if 40+yo, immunocompromised, <12mo, or those with chronic liver disease or other underlying conditions give immunoglobulin

Crytosporidium parvum

found in cattle, attach to intestinal lining and cause watery diarrhea waterborn, acid-fast oocysts, resistant to chlorine

Yersinia pestis virulence factors

fraction1 (F1): capsular antigen with antiphagocytic effect V antigen (protein) and W antigen (lipoprotein); unique to genus; fx unknown

*vector-borne

from biting arthropod vectors

blood agar

general and differential alpha-incomplete rbc lysis-green halo appears around bacterial colonies beta-complete rbc lysis-clear zone of hemolysis around colonies gamma-no hemolysis

agars

general e.g. blood agar differential e.g. blood agar (hemolysis), MacConkeys, mannitol salt selective-inhibits growth of select bacteria e.g. MacConkeys, mannitol, sugar

bacterial naming

genus and species also categorized by gram stain, morphology and metabolic characteristics

hepatitis A prevention

good hand hygiene, heat foods to 185F, drink bottled water, avoid raw food in endemic areas, disinfect with bleach water, vaccines, immunoglobulin

HIV virion

gp120 (docking glycoprotein), gp41 (transmembrane glycoprotein), integrase, capsid, matrix, reverse transcriptase, viral RNA genome, nucleocapsid, liquid membrane, protease, Vif, Vpr, Nef, and p7

Kahoot-thick peptidoglycan layer vulnerable to lysozyme and penicillin attack

gram +

Dr. North Strep pneumo summary

gram + dx: CXR, test CSF or blood, noninvasive urine test observe: nonmotile pairs WHO recommends childhood vaccination DOC-PCN

Actinomyces Israelii

gram + beaded, filamentous, fungi-like aerobic organism normal flora of mouth and GIT that causes eroding abscesses following trauma to mucus membranes microscopic inspection of pus reveals "sulfur granules"

potential pathogens for sepsis

gram +: S. aureus and epidermis, MRSA, Strep pneumoniae, E. faecalis and faecium gram -: E. coli, P. aeruginosa, A. baumanii, Klebsiella, Serratia, Enterobacter, Proteus anaerobes: consider C. diff in pts with diarrhea with recent abx fungal: *Candida,* Cryptococcus, Coccidioides, Fusarium, Aspergillus

Dr. North RTI summary

gram +: S. aureus, GAS, GBS, S. pneumo, Diphtheria gram -: H. influenza, B. pertussis, Pseudomonas atypical: M. pneumoniae, C. pneumoniae, Legionella pneumophila

Acinetobacter baumanni

gram - coccobacilli, aerobic, doesn't ferment lactose, MDR pathogen antiphagocytic capsule; causes pneumonia, burns, sepsis, UTI occurence-colonizes and infects sick, immunocompromised hospitalized patients reservoir-soil, water, skin, secretions transmission-medical devices, hands of healthcare workers DOC imipenem/meropenem (Colistin has most evidence for MDR use)

Dr. North Pseudomonas summary

gram -, HAI, affects immunocompromised (BEPSEUDO) diagnosis: blue-green lab cultures fresh tortilla or grape-like smell DOC-combo of an abx with antipseudomonal activities and an aminoglycoside -beta-lactam (penicillin, cephalosporin) or carbapenems (imipenem, meropenem)

Bacterial Components Responsible for Toxic Effects

gram -: endotoxin; gram +: exotoxin

*If the shape is in the name...

gram positive!!! (But not all gram positives have a shape in their name)

*sepsis treatment tips

guidelines state that you identify sepsis and start antimicrobials within 1 hour

acne

hair follicles are clogged with dead skin cells and sebum cause: Propionibacterium acnes (85%), S. aureus topical benzoyl peroxide - mild to moderate cases retinoic acid (Accutane) - severe cases only -CI: pregnancy (REMS-Risk Evaluation and Mitigation Strategies) -BBW for suicidal ideation

toxoplasmosis sx

healthy-usually asymptomatic or may have "flu-like" symptoms pregnant-miscarriage, stillbirth, congenital defects possible immunocompromised-can be fatal if untreated-HA, fever, seizures, AMS

CORONA viridae

helical, enveloped, + stranded RNA e.g. respiratory illness (cold)

FILO viridae

helical, enveloped, - stranded RNA e.g. Ebola virus

ORTHOMYXO viridae

helical, enveloped, - stranded RNA e.g. influenza virus (A, B, and C)

PARAMYXO viridae

helical, enveloped, - stranded RNA e.g. mumps, measles

RHABDO viridae

helical, enveloped, - stranded RNA e.g. rabies virus

Septic Shock Complications

hemodynamic instability (severe hypotension), DIC (Disseminated intravascular coagulation), ARDS (Acute respiratory distress syndrome-damage to alveoli), multiple organ failure

hepatitis B pathophysiology

hepatocellular injury-cytotoxic immune rxn, cirrhosis, hepatocellular carcinoma HBsAg (surface)-detectable at onset of sx, antiHBsAg in vaccine HBeAg (envelope)-present in acute infection, high degree of infectivity, may indicate infection resolution and some mutants do not express this (refractory) HBcAg (core)-promotes immune mediated cell death-immune by infection only

tuberculosis cell wall

high lipid content (60%) makes it hydrophobic and resistant to many disinfectants, common lab stains or destains (acid-fast), abx, and host immune response responsible for virulence, resistance, permeability, and disease persistence gram positive, popular target for drug therapies proteins-important antigens that can be extracted and partially purified (PPD)

gram negative

high lipid content, porin channels three layers: inner cytoplasmic membrane, periplasmic space, thin peptidoglycan layer (5-10%), outer cell membrane (lipid layer-contributes to resistance) endotoxin (LPS)-lipid A resistant to lysozyme and penicillin attack

Urogenital flora

high pH vagina (prepuberty and postmenopause)-Diphtheroids, Staph. epidermis, Streptococci, and E. coli low pH vagina-L. acidophilus, Corynebacteria, Peptostreptococci, Staphylococci, Streptococci, and Bacteroides urethra-commonly colonized by S. epidermis, Enterococi, and Diphtheroids -E. coli, Proteus, and Neisseria found in 10-30% of individuals -10^4 organisms/mL common and not indicative of UTI

HPAI

highly pathogenic avian influenza In 2004, over 120 million birds died or were destroyed as a result of a current avian influenza type, the H5N1 strain. This number is higher than the combined total bird deaths of all prior highly pathogenic outbreaks recorded throughout the world over the last four decades. The spring 2005 die-off of upwards of 6,000 migratory birds at a nature reserve in central China, caused by highly pathogenic H5N1, was highly unusual and probably unprecedented. In the past, only two large die-offs in migratory birds, caused by highly pathogenic viruses, are known to have occurred: in South Africa in 1961 (H5N3) and in Hong Kong in the winter of 2002-2003 (H5N1). Furthermore, the 2004 deaths occurred in just three months. In the subsequent months, H5N1 has expanded to include other wild birds as well as domesticated ducks, and its host range now also includes mammals. When compared with H5N1 viruses from 1997 and early 2004, H5N1 viruses now circulating are more lethal to experimentally infected mice and to ferrets (a mammalian model) and survive longer in the environment.

*Pathogens

highly virulent; rarely found without disease to host

pyogranuloma

histopathological-granulomatous reaction with any neutrophils

fungal endemics

histoplasmosis-southern blastomycosis-east, like a line through Minnesota to Louisiana coccifiomycosis-southwest

Ancylostoma and Necator

hookworm, major cause of anemia in the tropics

Latent Syphilis

host suppresses infection, no lesions, only evidence is a serological test early latent: <1y duration; late latent: 1+y duration (unknown duration tx like late)

*infection disease course

host-pathogen-specific, based on the progression and intensity of sx incubation period, prodromal stage, acute stage, convalescent stage, resolution stage

Food-seeking or food-supplying Associations

host: capable of supporting the nutritional and physical growth needs of another colonization: multiplication of another organism usually a microbe in or on a host mutualism: beneficial to both organisms commensalism: beneficial to one partner, but doesn't harm the other parasitism: the host is injured by the activities of the parasite infection: detrimental colonization of a host by a foreign organism

Kenya and poop use

human excrements to make briquets for cooking and heating burn longer and hotter than charcoal

Nightsoil

human waste being used to fertilize crops which leads to an increase in helminthes and other intestinal parasites

Norovirus susceptibility

humans and mammals-mostly children, elderly, and immunocompromised immunity only 6-14 weeks; same strain for 3-6mo symptomatic pts can be re-infected in 2-3y *link to human histo-blood group antigens (HBGAs) (O are most susceptible and B are the least)*

diagnosis syphilis

hx, known contact to an early case, s/sx in last 12mo, serologic test PE: oral cavity, lymph nodes, skin of torso, palms and soles, genitalia and perianal area, neurologic examination, abdomen identification of T. pallidum in lesion exudate or tissue-darkfield microscopy serological tests to allow presumptive dx -treponemal (qualitative) -nontreponemal (qualitative and quantitative-most common in the clinic) --not specific for T. pallidum, titers correlate with disease activity --VDRL and RPR used to follow response to therapy --may be reactive for life "serofast"

favic

hyphae and empty spaces (honeycomb) pattern form inside the hair

PICORNA

icosahedral (20 little triangles), nonenveloped, nonsegmented, small ssRNA virus, one of the largest virus families, more than 230 members divided into 9 genera

HERPES viridae

icosahedral, enveloped DNA virus e.g. HSV type 1 and 2, varicella-zoster virus, cytomegalovirus, EBV

FLAVI viridae

icosahedral, enveloped, + stranded RNA e.g. dengue virus, hep C

HEPADNA viridae

icosahedral, enveloped, DNA virus e.g. hep B (requires co-infection with Delta virus to cause disease)

PICORNA viridae

icosahedral, naked, + stranded RNA *e.g. polio, hep A, rhinovirus (cold)*

PAPOVA viridae

icosahedral, naked, DNA virus e.g. HPV

Capsids

icosahedral-formed by arranging polypeptides into a triangular capsomer, then combining 20 capsomers helical-capsomers bound to RNA and coils into helical nucleoprotein capsid exceptions: RHABDO is bullet shapes, POX in a BOX

*control of transmission

identification of animal hosts, reservoirs, and competent vectors interruption of transmission cycle

Risk Factors for Candidemia/Invasive Candidiasis

immmunocompromised (neutropenia, chemo, transplant, DM, chronic liver or kidney failure), prolonged invasive vascular devices (HD catheter, central venous catheter), TPN, necrotizing pancreatitis, recent major surgery, long-term abx tx, prolonged hospital admission, recent fungal infection, colonization in multiple sites

hepatocellular degeneration in hepatitis A

immune-mediated injury not a cytopathic effect of virus sx indicate the onset of immune response cytotoxic T cells-hepatocyte lysis-cellular immune response

*cyst

inactive, non-motile, infective stage of protozoa, excreted in feces minimal metabolism, but some organisms can divide within the cyst wall

*vehicles

inanimate objects/materials by which organisms get from one host to another; includes water, food, objects (called fomites) and biological products (e.g., blood)

*vaccination issues and challenges

incomplete/ineffective immunization long vaccine production timelines ASD concerns

HIV and increased risk of infection

increased risk of opportunistic infections when CD4<200 thrush, TB, herpes zoster, Pneumocystis jiroveci PNA, Cryptosporidial diarrhea, Mycobacterium, Cytomegalovirus, Toxoplasmosis gondii, Cryptococcal meningitis, Microsporidial diarrhea

transmission prevention of HIV

increased risk of transmission: STDs, acute and late-stage HIV infection, high VL decreased risk: condom use, male circumcision, ART, pre-exposure prophylaxis

stages of whooping cough

incubation: 7-10d prodrome/catarrhal: 2weeks, common cold sx with dry hacking cough paroxysmal: 2-4w, fever subsides, followed by burst of rapid, consecutive, forceful coughs followed by inspiratory "whoop", vomiting, leukocytosis convalescent: 3+w, decrease in severity/duration of paroxysms, development of secondary complications (pneumonia, seizures, encephalopathy)

Capsule Visualization

india ink stain is not taken up by capsules so encapsulated bacteria will appear to have transparent halos quelling reaction-Ab bind capsule which swells with water and can be visualized microscopically

*herd immunity

indirect protection from infectious diseases conferred by high rates of immunization in the population

cholera toxin

induces fluid secretion into the lumen of the intestine, causing diarrhea

acute clinical human reservoirs

infected and ill-thus their contacts and activities may be limited-more likely to be diagnosed and treated than carriers

*How avian influenza A/H5N1 might enter the U.S. bird population

infected poultry could be imported to South America where trade is less restricted and then wild birds that become infected migrate to North America

Visceral Tissue Infections

infection of liver through viremia and reticuloendothelial system infectious agents: hepatitis, yellow fever, EBV infectious mono, CMV, HSV

folliculitis

infection of the hair follicle e.g. pimple, sty, furuncle, carbuncle cause: Staph!!! P. acnes, Pseudomonas tx: *IND (incision and drainage)*, topical mupirocin, systemic abx in severe cases when not all of the pus could be removed

rotavirus transmission and tx

infection with 10 ingested viral particles, diarrhea helps to transmit out of the host stool will contain large amounts of virus (10^10 particles per gram) immunity-secretory IgA against VP7 and VP4 neutralize the virus rehydration therapy, but no specific antiviral therapy required vaccine administration at 2, 4, and 6mo-Rotateq (5 bovine viruses with antigens from 5 human viruses) and RotaRix (single-strain attenuated human rotavirus)

*pathogen

infectious disease agent Microbe that replicates either independently or with the host AND is capable of provoking an adverse response in the host

Kuru

infectious prion found almost exclusively among cannibals in Papau New Guinea sx: ataxia and myoclonus, then dementia, then death within months of sx onset

*Factors influencing agent of disease transmission

infectivity, virulence, pathogenicity, immunogenicity, antigenic stability, survival

*Tinea Capitis

infects the scalp primarily in children appears as an expanding ring and result in scaly red lesions and loss of hair

Summary of Cascade of Sepsis

inflammation affects microcirculation as arterioles become less responsive to vasoconstrictors and vasodilators and capillaries become less perfused histamine release from mast cells increases capillary permeability and third-spacing of fluid and protein in interstitial spaces inflammation promotes coagulation and antifibrinolysis (due to loss of protein) increased platelet aggregation d/t TXA2 formation of inflammatory molecules leads to organ tissue damage

acute bacterial sinusitis

inflammation and infection of the paranasal sinuses, or membrane-lined air spaces around the nose; nonspecific URT infection that persists beyond 7-14d most sinusitis is viral, but if the sx persist for 7 or more days, bacteria is suspect specimen collection: sinus puncture (anaerobic transport to lab, prompt processing, INVASIVE, rarely done) or sinus radiography (may be helpful but not routinely recommended for uncomplicated sinusitis cause: *S. pneumoniae, H. influenzae, mixed anaerobes, Moraxella catarrhalis*, S. aureus, GAS, C. pneumoniae, Pseudonmonas, other GNR adult: nasal discharge, congestion, maxillary tooth pain, facial or sinus pain children: nasal discharge and cough longer than 10-14d, 102+F, facial swelling, pain

prostatitis

inflammation of prostate gland and surrounding tissue due to infection usually occurs in males >30yo routes of infection similar to UTIs, with reflux of infected urine into prostate gland sterile urine reflex can cause chemical prostatitis altered prostate secretory fx and increased pH of secretions gram -: E. coli, Enterobacter, K. pneumoniae, P. mirabilis, P. aeruginosa, Serratia

conjunctivitis

inflammation of the conjunctiva associated with marked hyperemia and mucopurulent or watery discharge viral (adenovirus, HSV), bacterial (S. aureus, S. pneumoniaw, H. aegypticus, N. gonorrhoeae, Pseudomonas, Francisella tularensis, C. trachomatis), and allergic steroids for anti-inflammatory activity cold artificial tears or topical decongestants may help with sx for bacteria: FQ (gati-, levo-, moxi-), polymyxin B +trimethoprim, azithromycin

keratitis

inflammation of the cornea that covers the pupil and iris medically URGENT-can lead to impairment, blindness, or loss of the eye severe infections can be admitted to the hospital-risk of corneal perforation is high and the frequency and intensity of tx requires medical personnel

Endophthalmitis

inflammation of the internal coats of the eye, bacterial or fungal possible complication of intraocular surgeries-especially cataract surgery loss of vision and the eye itself are possible bacterial-haziness of vitreous is the key to diagnosis needle aspirate both vitreous and aqueous humor to culture

infections through ingestion

ingestion of pathogenic microorganisms or their toxic products-one of the most efficient means of disease transmission in humans. contaminated food and water-cholera, typhoid fever, dysentery, food poisoning, traveler's diarrhea, cryptosporidiosis, hep A

*disease without colonization

ingestion of preformed toxins so it will not respond to antibiotics treatment may include anti-toxin therapy

hepatitis A pathogenesis

ingestion, replication in oropharynx/GIT, transported to liver (more replication), shed in bile, transported to intestines, shed in feces, brief viremia, cellular immune response

Strongyloides

inhabits small bowel-more severe in immunosuppressed people

Fatal Familial Insomnia

inherited prion disorder that targets the thalamus to cause sleep disturbances, dementia, and death in approximately one year. *Average age of onset is 40yo.*

prion etiology

inherited-autosomal dominant mutation in PrP gene favors conversion to PrPSc infectious-exogenous PrPSc induced conformational change of host PrPC sporadic-possibly spontaneous conversion of wild-type PrPC to PrPSc

allylamines

inhibit fungal sterol synthesis (ergosterol) by inhibiting squalene epoxidase e.g. terbinafine, butenafine, Nafitifine (Naftin), amorolfine (Loceryl) Selectively blocks ergosterol synthesis by inhibiting squalene epoxidase (not found in animals)

ethambutol

inhibits mycobacterial arabinosyl transferases (essential component of cell wall) bacteriostatic against susceptible mycobacteria

prodromal stage of infection

initial appearance of symptoms in host with no pronounced clinical presentation and changes shared by a number of disease processes

transmission hepatitis C

injection drug use (60% of the US), receipt of donated blood products or organ, needle-stick injuries, vertical transmission (not breast milk), personal items contaminated with blood, sexual contact

*biological transmission

intermediate host or vector-transmission reflects adaptation of the parasite into a cyclic event between vertebrate host and arthropod vector-transmission cycle

Practical Considerations for Evaluating Patients for Ebola in the United States

international travels in last 21d, contact with confirmed ebola, symptoms of ebola if exposure and sx: 1. initiate basic infection control and assessment 2. identify 3. isolate 4. inform e.g. public health authorities

Cyclospora cayetanensis

intestinal coccidia, fecal-oral, diarrhea similar to Cryptosporidium C. cayetanensis only one known to infect humans, no known animal reservoirs first outbreak among medical residents in 1980 1996 Texas had 100 cases in 6w from contaminated raspberries oocysts, 10 microns, variably acid-fast

cutaneous amebiasis

intestinal or hepatic fistula, perianal ulcers, urogenital mucosa bathed in fluids containing trophozoites

Mtb interaction with alveolar macrophages

intracellular growth by inhibition of phagolysosomal fusion-blocks EEA1 (early endosomal autoantigen) secretions inhibit macrophage activation by IFN-gamma and induce macrophages to secrete TNFalpha-regulation of immune cells-causes acute phase reaction (inflammation, fever, weight loss, and tissue damage) produces ammonia to diminish the potency of intralysosomal enzymes via alkalization

fungal endophthalmitis

intravitreal amphotericin B 0.005-0.01mg in 0.1ml for aspergillus systemic antifungals for Candida

keratinases

invade only keratinized layers

amphotericin B

isolated from Streptomyces nodosus, active against most systemic fungi IV (poorly tolerated-chills, HA, nausea) and topical NOT oral (poor absorption) encapsulated into liposomes in an attempt to reduce pronounced renal toxicity

clinical presentation acute infection of hepatitis A

jaundice more common with increased age, majority >14yo flu-like (anorexia, nausea, fatigue, malaise, fever, and headache), RUQ abdominal pain, dark urine, alcoholic stools, pruritus labs -IgM anti-HAV (acute infection) and Total anti-HAV (IgM and IgG) -Mild elevation of LFTs -Increased bilirubin -Period of infectivity is 2 to 3 weeks before onset of jaundice to one week after jaundice

high yield pathogen classification overview

lack cell wall-Mycoplasma (atypical/walking pneumonia) and ureaplasma obligate intracellular-chlamydia and rickettsia filamentous/acid fast-Mycobacteria, Acinomyes (anaerobe), Nocardia GPC-Strep, Staph, Entero GPR-Listeria, Corynebacteria, Bacillus, Clostridium (anaerobe) GNC-Neisseria, Moraxella gram - nonenteric-H. influenzae, Pseudomonas, Legionella (and other ellas) gram - enteric-E. coli, Enterobacter, Klebsiella, Proteus, H. pylori, Salmonella, Shigella, Vibrio, Campylobacter, Bacteroides (anaerobe)

Norovirus disinfection

lack of lipid envelope that are susceptible to desiccation, heat, and detergents inactivated by heating over 60C, chlorine based disinfectants bleaches 5.25% household bleach (1000 - 5000 ppm or 5 - 25 tbsp per gallon water) polyquarternary amines such as benzalkonium and benzathonium chlorides PROPER HAND HYGIENE

*measles susceptibility

lack of vaccine, crowded conditions, malnutrition

Balantidium coli

largest parasitic protozoan, class ciliophora, more complex than amebae cyst ingestion, excystation, invasion of trophozoites into mucosal lining of small intestine, cecum, and terminal ileum funnel-like mouth called a cytosome, large and small nucleus involved in reproduction, food vacoules, and two contractile vacuoules worldwide, swine and monkeys (less common) as reservoirs fecal-oral, sx: diarrhea, persistent pain, perforated colon

monocytes

largest type of leukocyte with a horse-shoe shapes nucleus role in cytokine release and differentiate into macrophages and dendritic cells

Symptoms and pathogenesis of Giardia

latency, acute self-resolving diarrhea, and chronic syndromes associated with nutritional disorders, weight loss, and failure to thrive (can last for years) children more likely to be symptomatic initial infection is the most severe inclubation 1-2w (up to 75d) first signs: nausea, loss of appetite, upper GI upset followed by sudden onset: explosive, yellowish, watery, frothy, foul-smelling diarrhea with no blood or mucus other sx: flatulence, bloating. anorexia, "purple burbs" (foul sulfuric, resolves in 3-4d), malabsorption, steatorrhea, debility (loss of strength), weight loss

latex particle agglutination

latex beads tagged with antibodies

Norwalk "Noro" virus

leading cause of epidemic acute gastroenteritis "stomach flu" ssRNA, family calciviridae, incubation 12-48h N/V/D (non-bloody), abdominal cramps, myalgias severe dehydration-decreased urination, lack of tears, dry mouth and throat, lethargy, weakness, HA, fever, dizziness, sleepy self-limiting 2-3d (4-6d in hospital outbreaks and in children <11) vomiting more prevalent >1yo and diarrhea more prevalent <1yo severe illness rare-death mostly in nursing homes, schools, and camps "hyperemesis hemis" or "winter vomiting disease"

WNV in US

leading cause of mosquito-born encephalitis in US and Canada; most prevalent cause of meningoencephalitis in US (9/10 arboviral meningoencephalitis cases); cast fatality 10-12% in US; on course to replace St. Louis encephalitis virus

insects

lice (poor and crowded communities), fleas (plague), mosquitoes (most important arthropod vector), kissing bugs (feed on blood nocturnally, often near the mouth)

superficial mycoses

limited to outermost layers of skin and hair: tinea versicolor, tinea nigra, white piedra, black piedra don't elicit immune response and cause little to no discomfort, cosmetic problem

LPS

lipopolysaccharide on the outer membrane of GNR components-outer oligosaccharide chains (O-antigen), core polysaccharide, inner Lipid A (ENDOTOXIN)-released upon lysis where it causes systemic inflammation, fever, and possible fatal shock

What are soil-borne pathogens?

live in soil and are capable of causing disease in humans transmission from the soil even in the absence of infectious individuals EPO and STP-shigellosis overlaps the two groupings

*Endoparasites

live inside the host

*Ectoparasites

live on the surface of the host

Clonorchis sinensis

liver fluke Widespread in China, Japan, Korea and Taiwan, this parasite is acquired by ingestion of infective metacercariae in raw or pickled fish

Fasciola hepatica

liver fluke, primarily in sheep who become infected when they ingest metacercariae that have encysted on watercress adult trematode lives in the intrahepatic bile ducts of the liver fascioliasis can lead to severe anemia in humans

endoparasite

lives inside another living organism e.g. malaria, Giardia

phaeohyphomycosis tx and prophylaxis

local excision for subcutaneous and IV ampho B and oral flucytosine for invasive

prion characteristics

long incubation time (months to years) non-inflammatory process in the brain NO host immune response gradual increase in severity leading to death within months of onset of disease

*LPAI

low pathogenic avian influenza seen in H5 and H7 viruses in poultry mild sx like ruffled feathers and a drop in egg production, often undetected

meningitis diagnostic tests

lumbar puncture (LP) to collect several tubes of CSF perform MRI or CT first if pt has AMS or new onset seizures

three types of amebiasis

luminal: least severe, asymptomatic invasive dysentery: more common, bloody mucus-containing stools and pain invasive extraintestinal: trophozoites carried via the bloodstream

Paragonimus westermani

lung fluke, widespread in the far E and SE Asia, acquired by ingestion of infective metacercariae in raw or pickled crustaceans

*Kahoot-Which site in the body is usually sterile?

lungs

Kahoot-An increase in this WBC is usually indicative of a viral infection

lymphocyte

*antibiotics that target bacterial 50S ribosome

macrolides, lincosamides, chloramphenicol Don't need to know for exam 1

Prion Neuropathological Findings

macroscopic examination is often normal but microscopic examination includes neuronal loss, amyloid plaques, accumulation of PrP, and small empty microscopic vacuoules in neuronal tissue

calcitonin

made by thyroid gland to regulate calcium procalcitonin is its precursor made in the lungs and intestines

Chikungunya vectors

mainly Aedes aegypti and albopictus (tiger mosquitoes) occasionally Culex, Mansonia, Anopheles abrupt onset of fever and arthralgia, incubation for 2-4d sx: HA, myalgia, pain along spine, facial edema, peteciae, URT sx, bleeding gums in children, more severe in elderly recovery is generally 7-10d, but joint arthitics persist for 3-12mo (some 5+y) dx: typically clinical (large number of cases in area), RT-PCR tx: supportive care only

Clinical Presentation trichomoniasis

majority are asymptomatic (especially men) vaginitis-frothy gray or yellow-green vaginal discharge -pruritis, cervicla petechiae (strawberry cervix <2%) may also infect Skene's glands and urethra, where the organisms may not be susceptible to topical therapy Trichomoniasis has been associated with increased shedding of HIV

*chronic infection

markedly protracted and irregular course symptoms continuous or sporadic for months or years without convalescence

mast cells and basophils

mast cells-skin, mucoepithelial tissue, lining of small blood vessels and nerves basophils-circulate in the blood both bind IgE, complement, and microbial products release histamine and cytokines as part of allergic and inflammatory responses

acute stage of infection

maximum impact-rapid proliferation and dissemination of the pathogen tissue damage and inflammation due to toxic byproduct of pathogen metabolism, cell lysis, or immune response by host sx are pronounced and more specific to pathogen and site of infection

parasite

may be simple unicellular protozoa or complex multicellular metazoa all parasitic organisms are eukaryotes (well-defined chromosome in a nucleus) mostly invertebrates, mostly (sub)tropics

*WBC differential

may list as a percent instead of a value. If the percent on the lymphocytes are low it may just mean that the neutrophils are super high, etc.

macrophages

may reside in the tissue, spleen, lymph nodes, and other organs activated by IFN-gamma and TNF and play role as APC M2-inactive-remove debris, maintain normal tissue function, and facilitate repair M1-activated-initiate inflammatory and acute-phase response (antibacterial)

hookworm tx, prevention, and control

mebendazole (cheap)-100mg BID for 3 days bephenium hydroxynaphthoate "alcopar" in pregnancy ferrous sulfate TID for 3mo in anemia

*Arthropod-borne Pathogens

mechanical transmission when arthropods carry pathogens from one place or host to another host often via body parts biological transmission-multiplication or development or both in an arthropod

watery diarrhea

mechanism: intoxication, non-inflammatory enterotoxin in proximal small bowel Vibrio cholera, ETEC, C. perfringens, B. cereus, S. aureus

evaluation of TB

medical hx, PE, Mantoux tuberculin skin test, chest radiography, microscopy, histopathological exam, cx, haematological exam, DNA based detection

Clinical Syndromes Caused by C. trachomatis

men: urethritis, proctitis, conjunctivitis women: cervicitis, urethritis, proctitis, conjunctivitis infants: conjunctivitis, pneumonitis, pharyngitis, rhinitis

types of TB

meningitis, scrofula (lymphatics), pleurisy, millary (disseminated), Potts disease (bones and joints of spine), urogenital, pulmonary (most dangerous)

*thimerosal

mercury-based vaccine preservative that has been controversial

endospores

metabolically dormant forms of bacteria resistant to heat, cold, drying, and chemical agents. Can lie dormant for years and become active when exposed to favorable environment. germination-transformation from endospore to vegetative state possessed by only 2 pathogenic genera-both gram positive-bacillus (aerobic) and clostridium (anaerobic)

extraintestinal amebiasis

metastasis via blood stream primarily liver (portal vein) -other sites less frequent ameba-free stools common high antibody titers

mechanical vectors

microbes do not multiply in the vector e.g. biting insects with infected blood

dx schistosomiasis

microscopy for eggs in urine sediment for S. haematobium and stool samples for S. mansoni and S. japonicium rectal biopsy for S. mansoni ad S. japonicium serology, endoscopy, radiology, clinical observation

Clostridium perfringens diagnosis

microscopy, Nagler's reaction lecithinase test (test for the release of phospholipase)-bacterial lecithinase break down lecithin typically found in egg yolk into insoluble diglycerides resulting in an opaque halo surrounding the colony when grown on egg yolk agar medium

urine collection

midstream clean-catch (preferred method), catheterization, suprapubic bladder aspiration (usually newborns)

tetanus treatment

mild cases: tetanus immunoglobulin IV or IM, metronidazole IV for 10d, diazepam CAUTION: PCN can inhibit GABA just like tetanospasmin severe cases: tetanus immunoglobulin intrathecally, tracheotomy and mechanical ventilation, magnesium IV to prevent spasm, diazepam CIVI

arachnids

mites and ticks serve as vectors for bacterial, viral, and protozoan diseases ticks second only to mosquitoes for the number of diseases they transmit -hard ticks are the most prominent disease vector -e.g. Lyme disease, RMSF, tularemia, relapsing fever, and tickborn encephalitis mites wherever humans and animals coexist-transmit rickettsial disease

epithelioid granuloma

modified macrophages-epitheloid cells and Langerhans giant cells-forms "multinucleated giant cell that surrounds Mtb-central core made up of necrotic mass of intracellular mycobacteria surrounded by dense wall of macrophages, CD4, CD8 and NKT cells-encapsulation and isolation of lesion by dense membrane of connective tissue

dimorphic fungi

molds at 25C with spores that can become aerosolized inhaled spores grow as yeasts at body temp 37C

*epidemiologic surveillance

monitor and calculate expected frequency of infection or disease

types of TB resistance

mono-resistant, poly-resistant (but not both isoniazid and rifampin), MDR: at least isoniazid and rifampin (top two DOC), XDR (extensive): isoniazid and rifampin, PLUS resistant to any fluoroquinolone AND at least 1 of the 3 injectable second-line drugs (e.g., amikacin, kanamycin, or capreomycin) -DOTS - Direct Observation Treatment Short course (watch them take the medicine)

influenza vaccine production

month 1-WHO or other health agencies present proposed recommendations and seed strains to later grow in eggs month 2-adjust the strains to optimize vaccine's power month 3-injected into chicken eggs for incubation then harvested, purified, and tested for sterility month 4-initial batch tested in human clinical trials that demand them like Brazil and Canada month 5-before the vaccine is used in pts it is tested for potency and purity and approved by the FDA for wide distribution

*Gram (-) Facultative Anaerobes

most GNRs

Genital Gonorrhea Infection in Women

most asymptomatic cervicitis-abnormal vaginal discharge, intermenstrual bleeding, dysuria, lower abdomen pain, dyspareunia, mucopurulent cervival discharge, easily induced cervical bleeding, incubation period unclear, sx within 10d of infection urethritis-dysuria, 70-90% with cervical gonococcal also have urethral infection

occupational exposure of HIV

most cases have resulted from needlestick injury-0.3% risk of transmission mucicutaneous exposure-tainted blood contact-0.09% significant risk factors for seroconversion-deep injury, injury from device visibly contaminated with blood, advanced HIV disease in index pt

Cutaneous Anthrax

most common anthrax and least severe, extremely rare in US, GPR, spore-forming localized itching followed by a raised lesion that eventually form a painless *black eschar* within 7-10d DOC: Cipro and doxycycline; no tx available for toxin BioThrax-vaccine-required 5 doses within 18mo and an annual booster 20% mortality rate without tx

viral hepatitis

most common cause of liver disease, A-E, all cause acute, many asymptomatic B,C, D are associated with chronic (6+mo) which can lead to cirrhosis, end-stage liver disease, and hepatocellular carcinoma

candidiasis in immunocompromised hosts

most common in diabetes esophagitis-extension of thrush-substernal pain, worse when swallowing disseminated-can invade the blood stream, retinal exam may lead to diagnosis as fluffy white patches may be visualized during ophthalmological examination

clinical manifestations trichomoniasis

most common in older women, men often asymptomatic prevalence of invasive cervical cancer and prostate cancer with trichomoniasis increased preterm and low weight babies sx in women: foul, thin, frothy, green-yellow vaginal discharge; vulvovaginal irritation and redness sx in men: urethritis, chronic prostatitis sx in both: higher susceptibility to HIV, infertility

HSV meningitis

most common treatable cause of viral encephalitis early treatment necessary-high mortality rate without treatment (70%) tx: acyclovir IV as empiric therapy

HIV-1

most common; M-main/major; O-outlier N-non-M orO group M has 9 subtypes (B primarily responsible for the epidemic in North America and western Europe) similar to SIVcpz found in chimpanzees in west Africa

PID

most polymicrobial: N. gonorrhoeae, C. trachomatis moving further up pelvic floor-cervicitis-endometritis-salpingitis-peritonitis (ascending infection) 25% of women with just one episode of PID will have ectopic pregnancy, infertility, or chronic pelvic pain minimum criteria: uterine tenderness, adnexal tenderness, or cervical motion tenderness additional: >101F, mucopurulent discharge-abudant WBCs on saline microscopy more specific: endometrial biopsy, transvaginal sonography or MRI, laparoscopy

dendritic cells

most potent APC found in lymph nodes and tissue initiates and determines the nature of T-cell response

opportunistic mycosis

mostly Candidiasis (Candida albicans and others-dimorphic BUT also mold at 37C) and Aspergillosis (often cause epidemic death in birds) in immunocompromised; also Cryptococcus neoformans

tetanus diagnosis

mostly clinical presentation, difficult to culture due to extreme sensitivity to oxygen toxicity and low bacteriemia, no blood tests (toxins are bound to motor neurons and internalized) spatula test-touch posterior pharyngeal wall; positive test will result in involuntary contraction of the jaw; negative test will result in gag reflex

Prevnar 13

mostly for children

HIV-2

mostly in western Africa (subtypes A-G) found in sooty mangabey-"Hunter" theory that either eating the bushmeat or infected chimp blood contamination caused HIV in humans (zoonosis) usually longer asymptomatic stage than HIV1 but lower plasma RNA levels, and lower mortality rates

acute sinusitis

mostly viral, S. pneumoniae, H. influenzae, and Moraxella catarrhalis

trophozite

motile, vegetative stage of protozoa; multiplies via binary fission; colonizes host -metabolically active, parasite takes up nutrients, forms cysts

systemic candidiasis

mucocutaneous barriers breached in pts after surgery, burns dissemination to kidneys, skin, eye, heart, bone, liver, etc (often fatal)

metazoa

multicellular organisms, e.g. helminths (worms) and arthropods (ticks, lice) e.g. filaria, toxocara

first episode HSV

multiple lesions that are more severe, last longer, and have higher titers of virus progression: papules, vesicles, pustules, ulcers, crusts, healed fever, HA, malaise, and myalgia that lasts 2-4 weeks

*Actinomycetoma

multiple, diffuse with ill-defined margins, early in sinuses, inflamed and flared up, flap of opening easily removed, purulent discharge, white grains except A. pelletieri which is red, more extensive and obliterative with hypertrophic osteolytic lesions, more common than eumycetoma

tuburculosis patho

multiply in 4-6 weeks and spread throughout the body "lymphohematogenous seeding" in areas of high partial pressure of oxygen extrapulmonary-renal cortex, reticuloendothelial system (part of the immune system), brain, bones, and joints, miliary (all parts of the body through blood-rare) primary infection-pt will heal and a scar will appear in the infected loci but viable bacilli may remain in infected areas and become latent as long as the immune system is functional then may reactivate when immunosuppressed 85-90% of reactivation occurs in the lungs chemotactic factors from macrophages attract circulating phagocytes CMI (cell-mediated immune) response kills the AM and other infected cells results in epitheloid granuloma formation initial pulmonary site of infection and lymph nodes develop necrosis and radiographic calcification

Which viruses in the paramyxoviridae family have available vaccines?

mumps and measles

Isoniazid resistance in TB

mutation of katG gene producing inactive catalase-peroxidase so that there is no activation of the prodrug and thus failure of the drug to penetrate the microorganism by active transport system

Isoniazid for TB

mycobacterial catalase-peroxidase (*katG*) converts into active metabolite-a hydrazide of isonicotinic acid. It is bacteriostatic for resting bacilli and bactericidal for growing bacilli. DOC for TB-treatment is up to 2y *primary action seems to inhibit the biosynthesis of mycolic acids (part of cell wall structure)* which leads to loss of acid-fastness

Diseases Transmission in GIT

naked capsid viruses, no envelope, outermost covering of capsid made of proteins, more virulent than enveloped (cause lysis of cells instead of budding) resistant to heat, acid, and drying (retain infectivity) spread via fomites and close contact e.g. Norwalk virus, calciviruses, astroviruses, adenoviruses, reoviruses

How is bacteria acquired into CSF?

nasopharyngeal colonization of host mucus barrier contains IgA which work to inhibit bacterial colonization bacteria secrete IgA proteases which degrade protective mucus barrier degradation of mucus barrier allows bacterial adherence to the nasopharyngeal epithelial surface receptors bacteria cross the BBB from the blood into the subarachnoid space/CSF

control of HPAI in Vietnam

nationwide vaccination of poultry in 2005, gradually H5N1 reappeared, mostly in unvaccinated ducks, particularly in the Mekong delta

NKC

natural killer cell large, granular lymphocyte that kills Ab marked cells, virus-infected cells, and tumor cells by releasing perforin and granzymes to induce apoptosis

covert symptomatology

need lab testing to detect e.g. hepatitis, increased WBC, etc.

Indications for CSF Examination for syphilis

neurologic or opththalmic sx, evidence of active tertiary syphilis (gummatous lesions), tx failure, HIV with CD4 <350 and/or nontreponemal serologic titer >1:32

Kahoot-An increase in this WBC is usually indicative of a bacterial infection

neutrophils

*incidence

new cases within a defined population over a defined period of time

echinocandins

newest antifungals, well-tolerated inhibit synthesis of glucan in the fungal cell wall (likely block 1,3-beta gluca synthase)-mammalian cells have no cell walls e.g. caspofungin, micafungin, anidulofungin

UTI Testing in the Outpatient Setting

nitrite dipstick-gram + and Pseudomonas do not convert urinary nitrate into nitrite leukocyte esterase dipstick-rapid detection pyuria (neutrophils); indicates WBCs

*antibiotics that target DNA synthesis in bacteria

nitroimadazole (nitrofurantoin) Don't need to know for exam 1

lobomycosis tx and prophylaxis

no effective medical tx-complete excision and cryosurgery

ebola risk assessment-none

no risk if the person is not showing symptoms, the exposure was 21+d ago, travel areas with strict control measures despite active ebola cases, remain on boat in area with wisespread transmission (not airborn, needs direct contact with the infected), an ebola survivor (cleared by public health authorities to no longer be infectious)

taxonomic classification of parasites

no universally accepted system, 800,000 identified but estimated 10 million animal kingdom, 2 sub-kingdoms: protozoa (unicellular) and metazoa, 33 phyla 45,000 protozoa-most species that cause human disease belong to phylums sarcomastigophora and apicomplexa metazoa include helminths and arthropoda (ticks, lice) Genus species = Plasmodium falciparum or Giardia lamblia

hepatitis C prevention

no vaccine but vaccinate against A and B; abstinence from alcohol and smoking

Investigational Therapies for Ebola Patients

non approved for prophylaxis or tx, ribavirin not effective convalescent serum, vaccines, and therapeutic meds in trial Therapeutic meds -ZMapp - three chimeric human-mouse monoclonal antibodies -Tekmira - lipid nanoparticle small interfering RNA -Favipiravir - oral RNA-dependent RNA polymerase inhibitor Vaccines - in clinical trials -Chimpanzee-derived adenovirus with an Ebola virus gene inserted -Attenuated vesicular stomatitis virus with an Ebola virus gene inserted

*pathogen classification

non-cellular (viruses and prions) cellular (prokaryotes like bacteria and their products or eukaryotes like parasites, fungi, and protists)

rotavirus

non-enveloped spherical icosahedral dsRNA virion, double-layered capsid A-G, human disease by A (occasionally B and C) subgroups based on outer capsid proteins (VP7-glycoprotein G and VP4-protease sensitve P) proteolytic digestion of the outer capsid by intestinal enzymes (trypsin) activates the virus for infection to produce ISVP (intermediate subviral particle) stable to environmental abuse of detergents, repeated freezing, and pH 3.5-10 damages transport mechanism in the gut and prevents absorption of water as many as 10^10 particles per gram of stool no inflammation or blood loss, respiratory sx common fatal <2yo, kills 1,000,000 annually IgA in colostrum protects for the first six months of life common cause of hospitalization in children-dehydration underdeveloped environments and undernourished population

trematodes

non-segmented, usually leaf-shaped with two suckers but no distinct head alimentary canal, usually hermaphroditic with the exception of schistosomes e.g. Fasciolopsis (liver fluke), Schistosoma (thread-like), Clonorchis, Paragonim

clinical features ebola

nonspecific early sx progress to hypovolemic shock, multi-organ failure, hemorrhagic disease, and death nonfatal cases typically improve 6-11d after sx onset fatality rates of 70% in rural Africa early IV and electrolyte management may increase survival rate

subcutaneous mycosis

normally soil inhabitants who gain entrance through trauma to the skin and usually remain in the subcutaneous tissue and lymphatics involving the dermis, subcutaneous tissues, muscle, and fascia infection usually follows trauma. lesions develop at the site of implantation of the etiological agent in the subcutaneous tissue. e.g. mycetoma, sporotrichosis, rhinosporidiosis, chromoblastomycosis, phaeohyphomycosis, lobomycosis

persistent HPV infection

not cleared by immune system, persistently detectable type-specific HPV DNA persistent oncogenic type is most important RF for precancerous changes and cervical cancer

diagnostic features of protozoa

nuclear structure useful in species differentiation size helpful in identifying organisms cytoplasmic inclusions like chromatoid bars (coalesced RNA), RBCs, food vacuoles containing bacteria, yeast, etc. cytoplasm is smooth and clean or vacuolated directional or non-directional motility; sluggish or fast

HIV-1 NAT

nucleic acid test for acute HIV-1 infection

Epidermophyton floccusom

numerous macroconidia (smooth walled), absent microconidia athlete's foot

Microsporum canis

numerous macroconidia (thick walled, rough), rare microconidia tinea capitus and tinea corporis

oxygen utilization types

obligate aerobes-require oxygen for life and possess all three enzymes to break down oxygen byproducts e.g. M. tuberculosis facultative anaerobes-mostly aerobic, but can be anaerobic and use fermentation for energy e.g. Staph, some Strep, E. coli microaerophilic-AKA aerotolerant anaerobe-possess superoxide dismutase to tolerate low amounts of oxygen e.g. Campylobacter, H. pylori, Strep obligate anaerobes-can not grow in the presence of oxygen e.g. Bacteroides, Clostridium, Actinomyces

Dr. North Chlamydophila pneumoniae summary

obligate intracellular organism, major cause of pneumonia, no vaccine Taiwan acute respiratory agent (TWAR) 183, 497, 239

*predisposing factors to UTI

obstruction-incomplete emptying thus unable to remove bacteria from bladder -BPH, urethral strictures, calculi, tumors, bladder diverticula, anticholinergics neurological malfunctions-stroke, DM, spinal cord injuries vesicoureteral reflux-urine forced up the ureters to the kidneys-congenital abnormality or bladder over distension from obstruction catheterization, mechanical instrumentation, pregnancy, spermicides, diaphragms

overt symptomatology

obvious like chicken pox or measles

Rheumatic fever

occurs 1-3w post untreated GAS pharyngitis M-protein antibodies target heart and synovial joints fever, migrating, polyarthritis, carditis, autoimmune dysfx

sepsis

old definition: SIRS secondary to infection life-threatening organ dysfxn caused by dysregulated host response to an infection or organ dysfxn identified as an acute change in total SOFA score (2+) SOFA-sequential (sepsis-related) organ failure assessment pts with suspected infection who are likely to have prolonged ICU stay or die in the hospital can be promptly identified at the bedside with qSOFA (quick) -one of the following requires further investigation: AMS, RR 22+, SBP <=100

Facultative Intracellular Organisms

once phagocytosed, can live inside host macrophages and neutrophils by inhibiting phagosome-lysosome fusion Listen Sally Yer Friend Bruce Must Leave Now Listeria monocytogenes, Salmonella typhi, Yersinia, Francisella tularensis, Brucella, Mycobacterium, Legionella, Nocardia

commensial fungi

one benefits one is not harmed

HPV

one of the most common STDs, more than 40 types either low-rsk (nononcogenic) or high risk (oncogenic) most transient, asymptomatic, no clinical consequences dsDNA, papillomaviridae family HPV DNA detection-identifies infection HPV infects the basal cell layer of stratified squamous epithelium and stimulates cellular proliferation affected cells display a broad spectrum of changes, ranging from benign hyperplasia to dysplasia, to invasive carcinoma time of development is variable, median duration of cervical infection is 8mo 90% of infections clear within 2y gradual development of an effective immune response is the likely mechanism for HPV DNA clearance

Enteric Or Typhoid Fever

only in humans-acute generalized infection of reticulo-endothelial system, intestinal lymphoid tissue, and the gall bladder typoid fever by Salmonella typhi; paratyphoid fever by S. paratyphi A, B, and C typhos-Greek cloud-believed to cause disease or madness in advances stages-delirium and clouded level of consciousness survive stomach acid pH, attach and penetrate the gut mucosa in small intestine diarrhea by direct mucosal damage and by action of exotoxins invade lymphoid tissue in the GIT (Peyer patches), multiplication within macrophages leads to bacteremia essential lesion: proliferation of RES (reticuloendothelial system) typhoid nodules-specific changes in lymphoid tissue and mesenteric lymph node most characteristic lesion: ulceration of mucous, region of Peyers patches leading cause of osteomyelitis in children with sickle cell anemia

Hot Tub Folliculitis

opportunistic Pseudomonas infection in warm, moist environments itchy spots on the skin that become a bumpy red rash that is worse underneath the swimwear dx: pt hx and C&S tx: usually self-limiting and will resolve in 2-7d -levofloxacin and ciprofloxacin are the only PO meds Pseudomonas typically only in immunocompromised people with this exception

*Factors Influencing Exposure and Infection: Host Factors and Host Susceptibility

opportunities for host exposure-transmission routes, host availability susceptibility factors-dosage, virulence, age, immunity, nutritional status, genetics, immunocompetence and health status, behavior of host

endogenous

opportunitistic infections acquired from host's own microflora

Oral and Respiratory Tract Flora

oral cavity-alpha and beta-hemolytic streptococi predominate in this region URT-Streptococci, Staphylococci, anaerobes, Neisseriae, and diphtheroids, often the initial site of pathogenic bacteria colonization (N. meningitides, C. diphtheriae, Bordatella pertussis) LRT-normally sterile due to alveolar macrophages and mucociliary clearance

candidiasis in immunocompetent hosts

oral thrush-creamy white patches on oral mucous membranes that are difficult to scrape off vaginitis-20 million cases/year, most from abx or OCs during menses or pregnancy diaper rash

viral families affecting the respiratory tract

orthomyxo, picorna, paramyxo, corona, adeno

influenza

orthomyxoviridae, thought to be due to "influence" of stars, type A, B, C 1918 Spanish flu killed 20 million people characterized by sudden onset of fever, chills, muscle ache (myalgia), and HA cold sx like nasal inflammation and discharge, sore throat, and cough transmitted person-to-person by the aerosols created by coughing and sneezing type A subtypes based on receptor spike proteins called hemagglutinin (H) and neuraminidase (N) H binds respiratory cells. N breaks down respiratory mucus. enveloped, cylindrical capsid, -ssRNA

*OE

otitis externa; "swimmers ears", inflammation of the outer ear and ear canal cause: introduction of sharp object that disrupts the lining or moisture in the canal which softens the lining that allows antimicrobial growth pain, swelling, breakdown of skin and subcutaneous tissues of external canal acute infection usually secondary to S. aureus, Pseudomonas, Enterobacter chronic usually secondary to seborrhea fungal from Candida or Aspergillus malignant is Pseudomonas in >90%, also GAS and S. aureus external drops or ear wick (gauze with medicine) if edema is present for 24-48h goals: eradicate the organism, restore the acidic environment, and decrease pain

OM

otitis media-AOM (acute), OME (effusion), COM (chronic) *40-75% are viral,* AOM often follows viral URI-cause esustachian tube swelling *S. pneumoniae, H. influenza, Moraxella catarrhalis,* S. aureus, GAS, and more bacteria that colonize the nasopharynx enter the middle ear and are not cleared effectively by the mucociliary system

Plasmid gene confer pathogenicity/virulence in anthrax

pXO1: encodes PA, EF, and LF which are nontoxic individually, but toxic combined PA (protective antigen): highly immunogenic protein that promotes entry of EF and LF into phagocytic cells EF (edema factor): calmodulin-dep AC impairs neutrophil fx, massive edema LF (lethal factor): zinc metalloprotease toxin that inactivates protein kinase leading to cell death; stimulates macrophage to release TNFalpha and IL1beta Combination: hemorrhagic mediastinitis (bleeding into spaces surrounding heart and blood vessels), bloody pleural effusion, ARDS pXO2: encodes poly-D-glutamyl (glutamic acid) capsule (no other bacteria has protein capsule), inhibits phagocytosis of replicating cells

Tinea Nigra

painless dark patches on the soles of hands and feet from Exophiala werneckii

Which virus causes mumps and what are the symptoms of infection?

paramyxovirus characterized by fever, swelling of the salivary (parotid) glands, orchitis in males

roundworm life cycle

parasites of almost all vertebrates, adults only found in definitive hosts most intestinal nematodes shed their eggs into the lumen of the intestine, eggs are eliminated in feces and consumed in contaminated food or water some release their eggs into the soil, larvae actively penetrate the skin of a host others encyst in muscle tissue and are consumed in undercooked meat mosquitos transmit a few

dermatophytosis

parasitic infection (dermatophytes), feed on keratin, thrive on moist warm skin 1. Trichophyton 2. Epidermophyton 3. Microsporum

*definitive therapy for infections

pathogen definitively identified antibiotic susceptibility known focused narrow spectrum abx that are safe, effective, and reasonably priced avoid treatment failures, toxicities, and emergence of resistance

Neurologic damage

pathogens don't directly damage, but rather the host's inflammatory response inflammatory pathways result in: cerebral edema, elevated ICP, CSF pleocytosis (increased WBC), coma, death, decreased cerebral blood flow (ischemia)

HPV treatment

patient applied: imiquimod cream provider administered: surgery, cryotherapy, trichloroacetic acid

*empiric therapy for infections

patients with suspected infection, but the pathogen has not been identified choice of therapy based on signs and symptoms

*PCN

penicillin

carrier human reservoirs

people who harbor infections but are not ill incubatory carriers-begin transmission before full blown disease inapparent infections (subclinical)-do not develop disease, but can transmit convalescent carriers-continue to be infectious after recovery chronic carriers-harbor infections years after recovery

antimicrobial peptides

peptides produced by neutrophils, macrophages, epithelial cells, etc. that are toxic to microbes defensins-small cationic peptides that can disrupt membranes, kill bacteria and fungi, and inactivate viruses cathelcidins-cleaved to produce microbicidal peptides which disintegrate cell membranes of susceptible organisms

coronavirus cold transmission

person-to-person, droplet, poorly cooked pork

diseases with exotoxins

pertussis, anthrax, traveler's diarrhea, TSS, food poisoning

neutrophils

phagocytose bacteria via attachment, internalization, and digestion increased number on neutrophils in the blood is indicative of a bacterial infection infection also leads to recruitment of immature neutrophils (bands)-"left shift"

enteroviruses

piconaviridae family-small icosahedral ssRNA viruses e.g. Coxsackie virus, polio naked capsid (no envelope)-impervious to stomach acid, proteases, and bile very few cause disease in the GIT; fecal-oral; acquired through mouth and URT infect mucosa and lymphoid tissues, M cells and lymphocytes and spread to lymph nodes, spleen, and liver

Enterovirus 68 (EV68, EV-D68, HEV68)

picornoviridae, enterovirus, rare, first isolated in CA worldwide increase in 2000s-polio-like disorder called acute flaccid myelitis unenveloped, ssRNA virus containing poliovirus, coxsackievirus, and echoviruses unlike all other enteroviruses, EV68 displays acid lability and a lower optimum growth temperature, both characteristic features of the human rhinovirus, previously called human rhinovirus 87 by some researchers mostly sporadically in isolated cases; six outbreaks (10+ cases) between 2005-2011 in Philippines, Japan, the Netherlands. Georgia, Pennsylvania, and Arizona found in 2/5 of children in 2012/13 cluster of poliolike disease in California 2016-29 cases in Europe (France/Scotland, Sweden/Norway/Spain) typically during August and September in the Northern Hemisphere

endotoxins

piece of the outer membrane LPS (lipid A) of *gram -* organisms that is shed in steady amounts as living bacteria large amounts released when bacteria are lysed e.g. abx tx have no enzymatic activity, lipid portion confers toxic properties to the molecule potent activators of a number of regulatory systems endotoxic shock-small amounts of endotoxemia induce clotting, bleeding, inflammation, hypotension, and fever

Pseudomonas aeruginosa virulence factors

pili and LPS; endotoxin A (ETA-disrupts protein synthesis); exoenzyme S and T (destroy epithelial cell and tissues leading to pathogen spread); elastase and alkaline protease (destroy tissues and complement and cause lesions); phospholipase C (tissue destruction)

*Kahoot-short straight filaments that aid in attachment

pilli

Enterobius vermicularis

pinworm/threadworm, rare in tropics and prevalent in cold or temperate climates diagnosis with cellophane tape, females longer and thicker pinworm disease is the most prevalent helminthic infection in the US

*Reservoirs

place where organisms live, accumulate, or persist outside of the host of interest

Staphylococcus aureus

pneumonia, endocarditis leading to HF, stroke, bacteremia, sepsis, osteomyelitis RF: DM, cancer, vascular disease, eczema, lung disease (most have), hospitals MRSA-methicillin-resistant; VISA-vanc-intermediate;; VRSA-vanc-resistant

antifungal summary

polyenes-bind to ergosterol and disrupt membrane integrity polyoxins-inhibit chitin synthesis azoles and allylamines inhibit ergosterol synthesis griseofulvin disrupts microtubule aggregation during mitosis 5-fluorocytosine is a nucleotide analog that inhibits nucleic acid synthesis

*antibiotics that target RNA polymerase in bacteria

polymyxin Don't need to know for exam 1

*antibiotics that target bacterial cell membrane

polymyxin Don't need to know for exam 1

*Site of infections after pathogen penetration

portal of entry does not dictate site of action transmission related to the number of infectious agents absorbed by the host

tetanus prevention

potent toxin (LD50 of 1ng/kg) does not produce post-infection immunity tetaus toxoid vaccination q10y (3 in lifetime); combined vaccine <7yo DPT/DTaP

Group A Beta Streptococcus - Strep Throat Clinical Features

potentially serious pharyngitis-sore throat, fever, creamy white patches rare, but serious sequelae: pneumonia, bacteremia, cellulitis, scarlet fever, glomerulonephritis, necrotizing fascitis

human-poultry interaction

poultry on the Siliguri Darjeeling highway harbored the H5N1 virus and helped it spread to West Bengal where 4,000,000 poultry had previously been culled Panchayat elections severely affected containment and control as state officials in 4 districts did not want to intimidate villagers by taking away their birds (2008)

procalcitonin

precursor to calcitonin that gets ramped up during an infection and can be used as an indicator for sepsis

Obtaining Food at the Expense of Other Animals

predation-attach and consume part or all of a living animal scavenger-consume dead animals symbiosis-intimate association primarily for food getting on the part of one or both members of the group

normal skin flora

predominant organisms varies by location Staph. epidermis inhabits 90% of outer skin surfaces S. aureus-inside nose, perineum, fingernails micrococi-10% of bacteria on outer skin surfaces diphtheroids-commonly found on skin high in sebacious glands e.g. Proprionibacterium acnes) Streptococci-predominate oral flora and may spread to skin Gram - bacilli-moist skin like axilla and between toes

transmission of genital HPV

predominantly sexual activity even from asymptomatic and subclinical pts infectivity after treatment of genital warts or cervical abnormalities unknowns condoms may reduce risk

Zika and pregnancy

pregnant women are not more susceptible nor experience more severe disease infection during pregnancy CAN cause damage to the brain, microcephaly, or congenital Zika syndrome; linked to miscarriage, stillbirth, birth defects no evidence that past infection once cleared will affect future pregnancies

ebola transmission

present in high quantity in body fluids of symptomatic patients also transmitted via contact with bloods, fluids, or meat of an infected animal-no report of dogs or cats, limited evidence that dogs could become infected possible that the virus can be transmitted through the semen of a survivor

WNV prevention

prevent mosquito bites-DEET, picaridin, IR3535, oil of lemon eucalyptus (OLE), para-menthane-diol (PMD), 2-undecanone

PAM

primary amoebic meningoencephalitis Naegleria fowleri-thermophilic amoeboflagellate protozoan parasite and free-living amoeba that exist in nature without the need for a host. Globally distibuted in water (not salt water) and soil. Transmission: inhalation of infested water or mud (penetrate olfactory mucosa), 87% of cases occur during summer months Sx: high mortality rate with rapid progression, fever, HA, photophobia, nausea, vomiting, behavioral abnormalities, seizures, AMS, smell and taste disturbances

primary syphilis

primary chancre at site of inoculation (macule, papule, then ulcer) -*typically painless, indurated, clean base -highly infectious and heals spontaneously within 3-6 weeks regional lymphadenopathy-rubbery, painless, bilateral serological tests may not be positive during early primary syphilis

clinical course HIV

primary infection (may have acute mono-like syndrome), long asymptomatic stage, advanced disease with profound immunodeficiency and susceptibility to opportunistic infections

poverty and H5N1

primary source of food and income cannot be wasted so ill poultry consumed owners may not interpret signs of illness as a signal of avian flu absence of compensation for destroyed birds hinders reporting outbreaks and encourages owners to hide their birds during culling operations

insidious disease

prodromal phrase is protracted. The disease does not have marked symptoms but is ready to become active upon some slight occasion. Does not appear to be as bad as it really is.

Recurrent HSV Infection Without Treatment

prodromal sx common (tingling, irritation) 12-24h before lesions; lasts 4-6d sx less severe than primary; usually no systemic sx; HSV2 recurs more often

recurrent UTI

prophylactic antimicrobial therapy for 6mo; TMP-SMX, FQ, or nitrofurantoin

anthrax as potential biowarfare agent

pros: potentially lethal, tough and stable spores, easy to aerosolize cons: not communicable, relatively high infectious dose (10,000 spores), effective early tx exists

host defense mechanisms for prostatitis

prostatic fluid contains bactericidal zinc-complexed polypeptide normal pH 6.6-7.6 prevents bacterial growth

bacterial capsules

protective walls that surround cell membranes of some gram + and - organisms that are typically made of simple sugar residues. (Bacillus anthracis-aa residues) increase virulence through inhibition of phagocytosis if Abs directed towards the capsule, macrophages and neutrophils can engulf the bacteria through opsonization e.g. Strep pneumonia vaccine

exotoxins

proteins released from bacteria that enzymatically inactivate or modify key cellular constituents leading to cell death or dysfunction most gram + and some gram - neurotoxins e.g. tetanus and botulinum toxins enterotoxins-act on GI tract to cause diarrhea via NaCl excess or killing cells pyrogenic exotoxins-allow bacteria to destroy and tunnel through tissues

ebola

prototype viral hemorrhagic fever pathogen, FILO, enveloped, non-segmented zoonotic virus-bats most likely reservoir, also monkey, duiker no human-to-human transmission by inhalation, no transmission before sx

ciliates

protozoa that use cilia in their trophozoite stage, commonly found in animals B. coli is the only ciliate known to cause disease in humans trophozoites attach to the mucosal epithelium lining the intestine sx: generally asymptomatic in healthy adults, persistent diarrhea, abdominal pain, weight loss, dysentery results in severe infections complex cells with rudimentary mouth (cytostome) associated with pork

Cytoisospora belli

protozoan seen in immunocompromised, AKA Isospora belli, intestinal coccidia schizogony-sporozoites invade the intestinal epithelium and multiply sporogony-progeny of asexual reproduction infective stage-mature oocyst contains two sporocysts, each of which contain four sporozoites no intermediate hosts ranges from asymptomatic to acute, severe dysentery

types of specimens for TB

pulmomary-*sputum*, urine, blood, body fluid, tissue biopsy

pyrogenic toxins

pyrogenic toxin from Streptococcus pyogenes causes scarlet fever TSST-1 from S. aureus causes toxic shock syndrome

influenza antigenic shift

radical changes in influenza A viruses-occurs occasionally immune system cannot recognize them at all

H5N1 control measures

rapid culling of all infected or exposed birds, proper disposa; of carcasses strict bio-security measures, restriction on movement of live poultry no vaccine currently

epiglottitis

rapidly progressive inflammation which may cause airway obstruction sore throat, hoarseness, inspiratory strider, drooly culture attempts can cause complete obstruction esp in children-NEVER perform dx from presence of edematous "cherry red" epiglottis H. influenzae, S. pyogenes, S. pneumonie, S. aureus tx: cephalosporin and vancomycin, have tracheostomy ready for obstruction

subacute sclerosing panencephalitis

rare form of chronic progressive brain inflammation encephalitis that occurs years after measles infection

Trichophyton

rare macroconidia (thin walled, smooth), abundant microconidia Multicelled macroconidida and peg shaped microconidia athletes foot

cat scratch disease

rare subacute regional lymphadenitis caused by bacteria acquired from cats, dogs, or fleas; cause: Bartonella henselae (GNR) and endotoxin (lipid A) can live intracellularly; mostly affect the immunosuppressed usually self-limiting, but azithromycin, TCN, or FQ for severe cases

pulmonary amebiasis

rarely primary rupture of liver abscess through diaphragm 2o bacterial infections common fever, cough, dyspnea, pain, vomica

Serology/Immunology: ELISA

reactions of Ag and Ab are highly specific serology direct tests target Ags, indirect target Abs titer: highest serum dilution that gives a positive reaction acute infection = Ag on pathogen, or IgM, or 4+ fold increase between acute and convalescent serum titers enzyme-linked immunosorbant assay (ELISA)-easily assayed enzyme/reporter molecule covalently linked to an antibody performs Ag-Ab capture (immunosorbant) and the bound reporter gives a signal uses: Ag (hormone, enzyme, microbial Ag, drug), Ab (infectious agent exposure like HIV), biological fluids (blood, CSF, urine) and/or environmental samples

molecular tests

real-time PCR

*pre-exposure prophylaxis of hepatitis A

recommended to international travelers -for healthy pts-give vaccination at any time prior to departure -older adults, immunocompromised, or persons with chronic diseases departing within 2 weeks with mod-high hep A endemicity-give initial dose of vaccine plus IG at separate anatomic injection sites -<12yo, refusing vaccine, or allergies-give 1 dose of IG (works <3mo)

sepsis source control 2016 guidelines

recommends specific anatomic dx of infection requiring emergent source control should be identified or excluded as rapidly as possible in pts with sepsis, and that any required source control intervention should be implemented as soon as medically and logistically practical after the dx is made recommends prompt removal of IV devices that are possible source of sepsis after other vascular access has been established

specific symptomatology

reflect infection site-diarrhea, rash, convulsions, hemorrhage, pneumonia

endemic disease

relatively stable and expected incidence and prevalence within a population

*vaccine-mediated disease prevention

relies on adaptive immune response and immunological memory

hepatitis A in children

remain asymptomatic and infectious for longer periods of time-reservoir!

genital warts treatment

removal of warts; if left untreated they may regress spontaneously tx can induce wart-free periods but do not completely eliminate infectivity consider screening for additional STDs patient-applied and provider-administered tx options

spores

reproducing bodies of molds (rarely seen in skin scraping)

viral culture

requires live cells so it is performed in few laboratories. Instead viruses are diagnosed with sx and serology

amplifiers

reservoirs where organisms proliferate, often applied to airborne route

*Factors Influencing Exposure and Infection: Sources of Infection - Environmental Factors

reservoirs, amplifiers, vectors, vehicles

prion decontamination

resistant to: heat, chemical disinfection, irradiation decontamination relies on protein hydrolysis-Na hypochlorite and Na hydroxide

tuberculosis transmission

respiratory transmission; pts with active disease by coughing, sneezing, shouting minute aersol nuclei (<10 micron), prolonged or repeated contact required highly susceptible individuals-single, brief exposure and small number of bacilli

virus RNA exceptions

retroviruses-reverse transcribe into DNA to incorporate into host's genome. Then it can be transcribed into mRNA and translate into proteins e.g. HIV reoviridae-only viruses with a double stranded RNA genome e.g. rotavirus

*Post-streptococcal glomerulonephritis

reversible kidney damage; ARF with good prognosis occurs within 10d of GAS pharyngitis edema, HTN, hematuria, due to immune complex deposition

structure of bacteria

ribosomes, plasmids, nucleolus, cell wall, cell membrane, optional capsule

Rifamycins for TB

rifampin, rifabutin, rifapentine inhibits DNA-dep RNA polymerase, blocking production of RNA bactericidal activity against susceptible bacteria and mycobacteria

Ascaris

roundworm, world-wide, fecal-oral, adults in small intestine, causes eosinophilia

Which virus causes measles and how is it transmitted?

rubeola, paramyxoviridae family, very contagious, aerosol transmission

HIV etiology

sRNA, lentivirus, retrovirus, enveloped, SIV descendent (Simian)

treatment SARS

same tx as serious CAP of unknown cause, several treatment regimens used, but there is insufficient information of benefit DOC-antiviral agents such as oseltamivir or ribavirin sometimes administered with steroids and antimicrobials

how fungi get nutrients

saprotes-eat dead stuff, parasites-eat living stuff, can be both fungal spit-digestive enzymes used to break down food outside their bodies

eye structures

sclera (whites), cornea, conjunctiva, iris, pupil, lens, retina light rays focused by lens onto retina, optic nerve transmits image to brain, visual cortex converts it into a conscious image anterior chamber between lens and cornea, aqueous humor posterior between iris and lens, vitreous humor

tinea versicolor dx

scrapings on 10% KOH with or without calcofluor white may be visualized with hematoxylin and eosin (H&E) or PAS (periodic acid-Schiff) colonies composed of budding yeast-like cells with occasional hyphae fluoresce with yellowish color upon exposure to a wood lamp

AOM RF

seasonal outbreaks of flu or RSV, *day care centers, bottle feeding,*, aboriginal or iniut origin, early age of 1st dx, genetic predisposition, siblings in home, low socioeconomic status, *exposure to smoke, pacifier use*, males, immunodeficiency, allergy, urban population

Secondary Syphilis

secondary lesions occur several weeks after primary chancre; may overlap with primary stage; persists weeks-months rash, lymphadenopathy, malaise, mucocutaneous lesions, condylomata lata, alopecia, mucous patches, liver and kidney involvement, splenomegaly serologial titers highest in this stage

PAS for TB

secondline, para-aminosalicylic acid, structural analog of PABA (p-aminobenzoic acid), bacteriostatic, inhibits new synthesis of folates AE: GI irritation at high doses, N/V, bleeding, hypersensitivity reactions (rash, fever, some hepatotoxicity in 30-40% pts)

phaeohyphomycosis

seen in debilitated and immunodeficient hosts-subcutaneous and systemic dermatiaceous fungi most common genera-Alternaria, Bipolaris, Curvularia, Exophiala, Phialophora clinical types: brain abscess caused by Cladosporium, subcutaneous or IM lesions with abscess or cysts-single circumscribed lesion with a central cavity filled with puss and surrounded by a fibrous wall, cutaneous lesions

*MacConkeys

selective and differential for GNR fermenters-purple (KEE-Klebsiella, E.coli, Enterobacter); nonfermentors-colorless

mannitol salt

selective and differential for Staphylococci fermenter-S. aureus yellow, nonfermenter-all other Staph

azoles

selectively block ergosterol synthesis by inhibiting demethylation of lanosterol by inhibiting fungal CYP3A14-demethylase fungal P450 enzyme much more sensitive than mammalian counterpart fungustatic-active against systemic fungi and dermatophytes, resistance due to altered 14-demethylase imidazoles (clotrimazole, ketoconazole, miconazole, tiaconazole) and triazoles (Newer, less toxic, more effective!, fluconazole, itraconazole, voriconazole, posaconazole)

Jarisch-Herxheimer Reaction

self-limited reaction to antitreponemal therapy fever, malaise, N/V, may be associated with chills and exacerbation of secondary rash occurs within 24h after therapy not an allergic reaction to PCN (more frequent after PCN tx and tx of early syphilis) antipyretics can be used to manage symptoms but do not prevent the rxn may precipitate early labor so pregnant women should be counseled and should call OB if something happens

three defining characteristics of immune system

self/non-self discrimination, memory, specificity

antibiogram

sensitivity needs to be above 80 for use

septic shock

sepsis progresses to septic shock when not treated promptly and appropriately circulatory and cellular/metabolic abmormalities increase mortality (>40%) *sepsis with persisting hypoTN requiring vasopressors to maintain MAP 65+ and having a serum lactat level >2 mmol/L (18mg/dL) despite fluid resuscitation*

sepsis vs septic shock

sepsis: hypoTN, acute organ dysfxn 2ry to infection (lungs, heart/circulation, kidnes, CNS, hematologic/coagulation systems septic shock: sepsis + hypoTN persisting despite adequate fluid resuscitation (can gain a L in a matter of minutes), requires vasopressors

urisepsis

septic secondary to UTI

enteric fever

septic, penetrating systemic infection that begins in distal small bowel Salmonella typhi, Yersinia enterocolitica

SOFA

sequential/sepsis-related organ failure assessment parameters: respiration (PaO2/FiO2), coagulation (platelets), liver (bilirubin), cardiovascular (MAP or vasopressor use), CNS (Glasgow coma scale), renal (creatinine and UO) each category scored 0-4

What determines the site of infection of adenovirus?

serotype: respiratory-HAdV-B, C; conjunctivitis-B and D; gastroenteritis- F type 40, 41 and G type 52; obsestiy or adipogenesis-A type 31, C type 5, and D types 9, 36, 37

WNV Ab testing

serum or CSF testing for specific IgM antibodies detectable 3-8d after onset of illness and persist for 30-90d

PCT

serum procalcitonin, most common in gram - sepsis procalcitonin production in sepsis does not increase because of increased calcium levels that need to be regulated but because of inflammation produced by the neuroendocrine cells of the lung and intestine in response to inflammatory stimuli 2ry to bacterial infection (d/t bacterial endotoxin and inflammatory cytokines) *no value in the assessment of atypical bacterial, viral, and fungal infections or in local infections with no systemic response* PCT >2 ng/mL is detected in pts w/ bacterial sepsis and severe localized bacterial infections (PNA, peritonitis, etc.) no enzyme in the plasma to breakdown PCT *T1/2 PCT = 25-30 hrs and is increased in renal insufficiency* PCT release in response to bacterial infection does not result in increased serum calcitonin levels applications: -To aid in the diagnosis of bacterial sepsis -To aid in distinguishing bacterial from viral infections -To monitor therapeutic response to antibacterial therapy and reduce duration of antibiotic exposure *-Note: decision on initiating, altering, or discontinuing abx therapy should NEVER be made solely on the basis of changes in PCT*

pallisade

several parallel cells along long axis

SARS

severe acute respiratory syndrome-associated coronavirus first reported in Guangdong Province (China), Hanoi (Vietnam), and Hong Kong sx: fever, overall body aches, HA, feeling of discomfort, mild respiratory sx after 2-7d may develop a dry, nonproductive cough that may progress to a point of insufficient oxygen to the blood (10-20% require mechanical ventilation) dx relies on exclusion of other diseases and PCR to confirm

HIV modes of transmission

sexual-condom use reduces transmission risk 20-fold parenteral-needle sticks, infected blood products, affected organ transplants perinatal (vertical)-25% risk in absence of ART, 16.2% with breastfeeding not spread by air, water, insects, saliva, tears, closed mouth kissing, sharing meals

nonspecific symptomatology

shared by a number of diverse infectious diseases e.g. fever, myalgia, headache, and lethargy

pilli

short, straight filaments arising from cell wall (AKA fimbriae) that can not move, but can help serve as adhesins Neisseria gonorrhea-pilli adhere to cervical and buccal cells E. coli and Campylobacter jejuni-adhere to intestinal epithelium and avoid excretion in diarrhea Bordatela pertussis-adhere to ciliated respiratory cells

post-exposure prophylaxis hepatitis B

single dose of 0.06mL/kg IM anti-HBsAg used in conjunction with hep B vaccine avoid concomitant administration with live vaccines

*flagella configurations

single polar flagellum-Vibrio cholera multiple flagella-E. coli, Pr. mirabilis periplasmic flagella-specialized-Treponema pallidum, Borrelia burgdorferi

localized infectious disease

site specific- disease are rarely caused outside the tissue or body system Respiratory tract-Mycoplasma pneumoniae (influenza viruses), Legionella pneumophilia Genitourinary tract-Neisseria gonorrhoeae Gastrointestinal tract-Shigellosis, Giardiasis, Helicobacter pylori - gastric ulcers

*Determining Factors for Development of UTI

size of inoculum (portion of pathogen in contact with host), virulence of microorganism, competency of host defense

tinea nigra dx

skin scrapings in 10-20% KOH, pigmented hyphae and yeast cultures-mycologic media, appear within 3w, velvety look with age

*natural barriers

skin, mucus (captures airborne bacteria and viruses), ciliated epithelium (transports mucus), gastric acid and bile (inactivate many viruses and bacteria)

normal body flora

skin-S. epidermis, S. aureus, Micrococci, Diphtheroids lower resp-normally sterile small intestine: Lactobacillus, Streptococci, Enterobacter, Diphtheroids, few anaerobes, Enterococcus, Peptostreptococcus, anaerobes like Bacteroides and Clostridium mouth: Viridian streptococci and oral anaerobes URT-oral anaerobes, Streptococcus, Staphylococcus, Neisseria, Diphtheroides, Haemophillus stomach: Streptococcus, Lactobacillus large intestine: Enterobacter, Enterococcus, Pseudomonas, Streptococci, anaerobes including Bacteroides and Clostridium

Shigella

small GNR, nonmotile, obligate pathogen, non-lactose fermenters 4 species: sonnei (40-80% in US), dysenteriae (Shiga toxin), flexneri, boydii humans are the only host (children and elderly) low inoculum (<200 organisms), person-to-person spread invasion of intestinal mucosa, moving from small to large intestines with multiplication and mucosal destruction; penetration beyond mucosa is rare 12h after ingestion, bacterial multiplication causes abrupt abdominal pain, cramping, watery diarrhea, and fever (resolution of fever in a few days illness lasts for average 7d, shedding for 1-4w

influenza antigenic drift

small changes in the virus that happen continually over time (each year) new virus strains are produced and our immune system has trouble recognizing

antigenic drift

small genetic changes that accumulate over time to create antigenically different viruses; occurs frequently

chromoblastomycosis

soil saprobes enter the skin by traumatic implantation, commonly rotting wood warty cutaneous nodules which resembles flouts of cauliflower and frequently ulcerate-Verrucous dermatitis develops additional lesions months to years later. confined to subcutaneous tissue of the feet and lower legs caused by dermatiaceous (pigmented) fungi most common fungi-Fonsecaea, Phalophora verrucosa, Cladosporium carrionii

STP

soil-transmitted pathogens-not true soil organisms obligate pathogens who must infect a host to complete their life cycles Q fever-Coxiella burnetii; Lyme disease-Borrelia; Salmonellosis-Salmonella enterica; Shigellosis-Shigella dysenteriae, P. aeruginosa, and E. coli

phaeohyphomycosis dx

specimen from cyst aspiration or curetting from plaques, nodules, and abscesses KOH mount, pigmented hyphae, 3-4 micrometers in diameter actidione media at 25 and 37C

sporotrichosis dx

specimens from pus-exudate and aspirate nodules or swab open lesions "asteroid bodies" in lesion-central fungus cell surrounded by refractile eosinophilic halo called "Splendore Hoeppli" phenomenon, made from host-derived materials and parasite antigens culture at 25 and 37C, smear with septate hyphae that are small clusters of conidia on delicate sterigmata that resemble "pretty flowers"

spiral forms

spirochete, borrelia, treponema, spirilla

What organ rids the body of encapsulated organisms?

spleen those with spleen injury are more susceptible to infection of encapsulated bugs like E. coli and Klebsiella

*removal of encapsulated organisms

spleen removes encapsulated organisms patients with sickle cell are asplenic by the time they are 7 or 8. Then they have to take vaccines for strep pneumo and regular penicillin to kill encapsulated bacteria Don't need to know for exam 1

endothrix

spores inside the hair shaft

ectothrix

spores outside the hair shaft

mycosis

spread generally from the environment to people (or animals) with limited person-to-person spread. Skin and lungs are prominent entry site for many fungi Patients with impaired cell-mediated immunity (e.g. AIDS, organ transplant) at heightened risk for severe disease.

Direct Smear Microscopy for TB

sputum for AFB, Ziehl-Neelson/Kinyoun carbolfuchsin staining, fluorescence (Truant flurochome-Auramine or Acridine-orange) sensitivity 40-70% and specificity 90%

hepatitis C pathophysiology

ssRNA, not directly cytopathic, proliferative, persistently mutating virus immune response in acute infection insufficient to eradicate virus --> chronic 1.4% of pts each yeah develop hepatocellular carcinoma

incubation period

stage of active replication (colonizing) with no recognizable sx of infection short-salmonellosis (6-24h), Ebola (2-21d) prolonged-hepatitis (50-180d), HIV (months-years) influenced by general health of host, portal of entry, and infectious dose

*trichrome stain

stain commonly used for fecal specimens

gram stain for naming

staining allows better visualization of bacterial shape and structures as bacteria are colorless and often invisible to a light microscope gram positive-retains crystal violet stain-purple gram negative-crystal violet removed by alcohol, absorb safranin-pink

Gamastan S/D

sterile, preservative-free solution of IG for IM administration and is used for prophylaxis (passive immunizations) against disease caused by infection with hep A, measles, varicella, and rubella viruses avoid IG until 2 weeks after live vaccines and delay vaccines for 3mo after

*antibiotic sensitivity

subculture onto drug-free agar to grow survivors minimal bactericidal concentration (MBC) lowest drug level to kill bacteria minimal inhibitory concentration (MIC)-lowest drug level to inhibit replication-no visible growth, not turbid or cloudy, ALWAYS <MBC

Fontana Masson

subcutaneous mycosis

Non-Antimicrobial Remedies for UTI

substances in cranberry juice interfere with adherence of some pathogens Lactobacillus probiotics decrease vaginal pH and decreases E. coli colonization topical estrogen in postmenopausal women decreases vaginal pH also

fulminant illness

sudden and intense disease with little or no prodromal stage (Ebola)

*What signs/symptoms help distinguish the flu from a cold?

sudden onset of fever, chills, muscle ache (myalgia), and HA, N/V likely sx seen in both: nasal inflammation and discharge, sore throat, and cough

tinea nigra

superficial infection by Hortaea weneckii produce melanin, "dermatiacious" fungi grows as yeast and frequently branched septate hyphae as well as budding cells (sub)tropical-Africa, Asia, Central and South America children and young adults more common, female>male solitary, irregular macule usually on palms or soles, no scaling, NOT contagious or uncomfortable, often misdiagnosed as melanoma

treatment of acute hepatitis A infection

supportive treatment and transplant (liver failure) most have clinical resolution within 6mo watch for hepatotoxic drugs, dose adjustments, renal function, CBC, no alcohol during acute infection

HIV monitoring

surrogate markers: CD4 (immune fx indicator) and VL (viral load-copies of viral RNA in plasma-response to therapy indicator) goal of ART: VL undetectable (<20-75 copies/mL) resistance testing: genotype and phenotype

Patient Recovery in ebola

survivors often have signs of clinical improvement by the second week of illness -associated with the development of virus-specific antibodies, lasts 12 years prolonged convalescence-includes arthralgia, myalgia, abdominal pain, extreme fatigue, and anorexia; many symptoms resolve by 21 months; skin sloughing and hair loss has also been reported

HBV test results

susceptible: HBsAg (-), anti-HBc, (-) and anti-HBs (-) immune from natural infection: HBsAg (-), anti-HBc (+), anti-HBs (+) immune from vaccination: HBsAg (-), anti-HBc (-), anti-HBs (+) acute infection: HBsAg (+), anti-HBc (+), IgM-anti-HBc (+), anti-HBs (-) chronic infection: HBsAg (+), anti-HBc (+), IgM-anti-HBc (-) anti-HBs (-)

How long is a person with the flu infectious to others?

sx do not manifest for 1-4d contagious 1d before symptoms and up to 7d after becoming ill

SIRS

systemic inflammatory response syndrome = temp >100.4 or <96.8, RR >20, HR >90, WBC >12000 or <4000, bands >10%, PCO2 <32 mmHg

Echinococcus

systemic, E. granulosus (dog tapeworm) and E. multilocularis (rodent tapeworm) hydatid disease occurs when the larval stages of these organisms are ingested larvae may develop in the human host and cause space-occupying lesion in several organs e.g. liver, brain

botulism dx

tests are generally not helpful, dx based on clinical sx lab confirmation based on culturing C. botulinum in serum, stool, food, or wound Do NOT wait on confirmation to start treatment

Clostridium tetani

tetatospasmin (tetanus toxin) causes continuous motor neuron activity: uncontrolled muscle contractions with lockjaw, opisthotonus, and tetanic paralysis or respiratory muscles GPR, anaerobe, found in soil, dust, manure Usually enters body through broken skin like contaminated wounds or burns tetanus toxin-metalloprotease tetanospasm axonal transport allows the toxin to reach the spinal cord and brainstem toxin blocks inhibitory neurotransmission which results in increased muscle tone, painful spasms, and widespread autonomic instability incubation period-8 day average (3-21d) duration-prolonged because new axonal nerve terminals required for recovery (4-6w) GPR, anaerobic motile, round terminal endospore like a drumstick tetanolysin-oxygen-labile hemolysin (inhibited by cholesterol) generalized incubation: days-weeks depending on distance from CNS localized tetanus-muscle at site of primary action cephalic tetanus-head or brain (facial nerves)-poor prognosis neonatal tetanus-infection of umbillical stump that can progress to generalized -90% mortality rate and developmental defects in survivors

*antibiotics that target bacterial 30S ribosome

tetracycline Don't need to know for exam 1

*Who is most likely to be infected with a coronavirus?

the majority occur during the winter when people are couped up inside together

pandemic

the spread of disease beyond continental boundaries (global village).

Microsporidium

thought to be limited to AIDS patients, fecal-oral or sexually transmitted 1-1.7 microns, stain reddish pink with chromotrope stain some spores exhibit dark staining "belt" across the middle of the organism

hyphae

threadlike, branching, cylindrical tubules of fungal cells attached end to end

*Specimen collection tips not blood

throat-oropharynx and tonsils (no lips or cheeks) wound-debride and swab center of wound, minimize exposure to air to prevent contamination and help kill aerobes sputum-not spit, but a first morning deep specimen; induced or BAL reduces contamination

lab findings ebola

thrombocytopenia (50-100), leukopenia followed by neutrophilia, transaminase elevation (AST > ALT), electrolyte abnormalities, PT and PTT prolonged, proteinuria, increased creatinine

H5N1 in other mammals

tigers, leopards, pigs, cats, palm civets, humans

treatment of sepsis and septic shock

timeliness and appropriateness of therapy influences outcome

HPV DNA tests

to triage women with ASC-US Pap test results, and as an adjunct to Pap test screening for cervical cancer in women 30 years or older.

tx cutaneous mycosis

topical agents are usually effective if hair and nails are not affected (miconazole, clotrimazole, tioconazole, itraconazole, and terbinafine), oral agents for systemic (griseofulvin, itraconazole, fluconazole, terbinafine

miconazole

topical and PO for intestinal fungal infections also used in E6 slide film processing

clotrimazole

topical for Canididiasis and tinea

resolution of infection

total elimination of a pathogen from the body with no residual symptoms

Clostridium dificile

toxin A causes damage and toxin B causes binding both cause pseudomembranous enterocolitis abx: oral vancomycin and dificid (expensive)

toxoid

toxin that has been chemically modified to be non-toxic but still antigenic Td (Tenivac), TdaP (Adacel, Boostrix) less durable/strong immune response

enzymes of HIV

transcriptase, integrase, protease targets of ART

TSE

transmissible spongiform encephalopathies

Kahoot-Which enzyme is responsible for linking peptidoglycan?

transpepsidase

SIRS main causes

trauma, pancreatitis, burns NOT infection

RSV treatment

treat the sx; severe cases may require oxygen therapy and mechanical ventilation; ribavirin aerosol may be used in some; combo of RSV-IGIV (immunoglobulin IV) and ribavirin in patients with compromised immune systems ($1000/tx)

*TMP-SMX

trimethoprim-sulfamethoxazole

life cycle of Trichomonas vaginalis

trophozoite transmitted by direct contact during sexual intercourse, nonvenereal transmission is rare e.g. perinatal, sharing clothes survive 1-2d in urine and 2-3h on wet sponge attach to epithelium of urogenital tract replicate by binary fission

pathology Entamoeba histolytica

trophozoites contact with human cell: rapid influx of Ca into cell, all membrane movements stop, internal organization disrupted, organelles lysed, cell dies, ulcer formation (trophozoites found in ulcer exudate) amoeba takes nutrients from the dead cell trophozoites containing RBCs is indicative of tissue invasion submucosa, muscularis propia, serosa, small veins of submucosa little inflammatory response in early ulcers, but as it widens it accumulates neutrophils, APCs, lymphocytes, histiocytes, plasma cells and eosinophils tissue exam: granulation, fibrosis, chronic inflammatory cells extraintestinal ambiasis-muscle peneration, penetrate portal vessels and embolize to the liver where they form liver abscesses noninvasive: intestinal mucosa, asymptomatic cyst passer, nondystenteric diarrhea invasive: necrosis of mucosa leading to ulcers, dysentery, peritonitis -cessation of cyst production

Pathogenesis of Viral Diseases

tropism-disease caused by several viruses that infect the same tissue e.g. hepatitis one virus causes disease in several organs e.g. HSV1 severity depends on strain of virus, inoculum size (infecting dose), general health of pt

ear specimens

tympanocentesis-aspiration of fluid from middle ear required to make a specific diagnosis of OM, but unnecessary in most pts, treat empirically scraping-culture in outer ear infection typically Pseudomonas or S. aureus

gas gangrene toxins

type A: lecinthinase or alpha toxin type B: beta toxin-superantigen responsible for entertoxemia -hyaluronidase-facilitates spread of bacteria in tissue; hemolysin-destroys RBC; neurotoxin damages heart and nervous system type C: epsilon toxin-responsible for necrotizing enteritis (food poisoning, ulceration and perforation of intestines-pig bel), 50% mortality, peritonitis, shock responsible for most human infections-tissue infections, food poisoning, primary septicemia

broad-spectrum therapy

typically empiric since the usual purpose is to ensure antimicrobial coverage with at least one drug when there is uncertainty about the possible pathogen. On occasion, broadspectrum therapy may be continued into the targeted/definitive therapy phase if multiple pathogens are isolated e.g., piperacillin/tazobactam, vancomycin, and anidulafungin

Cryptococcus neoformans

ubiquitous, esp in pigeon droppings, meningitis as most common manifestation, complications in AIDS patients

protozoa

unicellular, chemotroph, absorptive food aquisition and ingestion with cytosome, motile, some form cysts, no embryo formation e.g. Plasmodium (malaria) trophozoite-vegetative, feeding, mostly motile; cyst-dormant, thick wall most are free living in water and soil 1. Sarcodonia-Amoeba-pseudopods 2. Mastiogophora-Flagellates 3. Cilophora-Ciliates e.g. B. coli 4. Apicomplexan-Sporoxoa-complex life cycle

URI

upper respiratory infection-AOM, acute sinusitis, acute pharyngitis, diphtheria

C. trachomatis Infection in Men

urethritis-NGU (nongonococcal urethritis), majority asymptomatic, mucopurulent, mucoid or clear urethral discharge, dysuria epididymitis and reactive arthritis

Genital Gonorrhea Infection in Men

urethritis-typically purulent or mucopurulent discharge (clear or cloudy) and often accompanied by dyuria. May be asymptomatic in a minority of cases. Incubation 1-14+d for symptomatic. epididymitis-unilateral testicular pain and swelling, infrequent but most common complication, usually associated with overt or subclinical urethritis

*UTI

urinary tract infection-microorganism not accounted for by contamination usually single organism cystitis-bladder, lower tract pyelonephritis-kidney infection, upper tract (treat 7+d even when uncomplicated) uncomplicated-no structural or functional abnormalities of the UT that interfere with normal flow of urine or voiding mechanism. (mostly premenopausal females) complicated-individuals with congenital abnormality, distortion of the UT, a stone, indwelling catheter, prostatic hypertrophy, obstruction, neurologic deficit that interferes with normal urine flow and urinary tract defenses. Always considered complicated in males e.g. kidney stone, paralysis, foley catheter, BPH, etc.

signs and symptoms schistosomiasis

urinary: gross haematuria, dysuria, bladder cancer; damage to bladder, ureters, and kidneys intestinal: gradual splenomegaly and hepatomegaly, HTN of abdominal blood vessels which begin to bleed causing bloody stools

Host Defense Mechanisms and UTI

urine: low pH, extreme osmolality, high urea and organic acid male: prostatic secretions bacteria in the bladder causes increased diuresis and bladder emptying individuals who do not void urine completely are at increased risk epithelial cells of the bladder are coated with urinary mucus/slime called glycosaminoglycan (made out of mucopolysaccharide, hydrophilic-forms water barrier between urine and bladder, strongly negatively charged) which prevents bacterial adhesion Tamm-Horsfall glycoprotein which contains mannose residues produced by ascending limb of Henle and distal tubule and secretes into the urine-mannose bind to Type I pili on E. coli and prevent it from binding mucosal surface systemic and local kidney IgG and A-decreased levels increase UTI risk bacterial bladder invasion stimulated an inflammatory response involving the mobilization of PMNs which phagocytize bacteria Lactobacillus growth in the vaginal flora is stimulated by estrogen. Lactobacilli produces lactic acid and maintains low vaginal pH. Thus topical estrogens are used to prevent UTIs in postmenopausal women for those with frequent UTIs who are not on PO estrogen

- RNA

use RNA-dep RNA polymerase to convert to + RNA before being made into protein

keratophilic

use keratin as subject to live ( parasites)

combination therapy

use of different mechanistic classes with the specific intent of covering the suspected pathogen(s) with more than one antibiotic (e.g., piperacillin/ tazobactam and an aminoglycoside or fluoroquinolone for gram-negative pathogens) to accelerate pathogen clearance rather than to broaden antimicrobial coverage. Other proposed applications of combination therapy include inhibition of bacterial toxin production (e.g., clindamycin with β-lactams for streptococcal toxic shock) or potential immune modulatory effects (macrolides with a β-lactam for pneumococcal pneumonia).

subunit, recombinant, and conjugate vaccines

usually require adjuvant for effective immunization recombinant: hep B (Engerix-B, part of Twinrix), HPV (Gardasil 9) conjugate: Hib (ActHIB, part of Pentacel), meningococcal (Menactra, Menveo), PCV13 (Prevnar) subunit: menigococcal (Bexsero, Trumenbra), pertussis (TdaP-Adacel, Boostrix), PPSV23 (Pneumovax) typhoid (Typhim VI)

Cervical Cellular Abnormalities

usually subclinical, detected on Pap, colposcopy with or without biopsy can be caused by HPV; low-grade lesions often regress spontaneously colonoscopy and cervical biopsy for further exploration

HIV prevention

vaccines in clinical trials, challenges due to lack of ideal animal model, and challenges due to mutations and multiple strains

substantial risk of HIV exposure

vagina, rectum, eye, nonintact skin, percutaneous contact, mouth or other mucous membrane contaminated with blood, semen, vaginal or rectal secretions, breast milk, or any body fluid visibly contaminated with blood

VRE

vancomycin resistant Enterococcus

vCJD

variant CJD-strong link to BSE (Mad Cow Disease) sx: psychiatric/behavioral sx, painful dysethesias, delayed neurological signs median age of death at 28 years typically within 13-14 months of symptom onset

*tineas

various forms of dermatophytosis: capitis, barbae, corporis, cruris, pedis, unguium

VAP

ventilator-associated pneumonia

herpes

very common, chronic viral infection from skin-to-skin contact cause: HHSV (human herpesvirus-dsDNA) 1 or 2 painful, itchy lesions on lips or genitalia that may be accompanied by flu-like sx HHV1 above waist and HHV2 below waist, but can technically be either place tx: no cure, but acyclovir and pencyclovir oral or topical may shorten outbreaks

Impetigo

very common, highly contagious, cause: S. aureus (80%) and Strep. pyogenes small, flattened, red patches that appear mainly on the face and limbs of children tx-topical mupirocin plus oral clindamycin or doxycycline (>8yo)

papillomas

very common, usually benign, viral growth of the epithelium on the skin or mucous membranes, cause: 100+ HPV strains (dsDNA) rough (wart) lesion that most commonly occurs on fingers and toes tx: surgery, freezing, cauterization, laser, or caustic chemicals vaccines: Cervarix (16 and 18, d/c in US), Gardasil (add 6 and 11), Gardasil 9 (add 31, 33, 45, 52, and 58)

HSV diagnosis

viral culture (gold standard) and PCR

sinusitis treatment

viral improves in 7-10d while bacterial has persistent or worsening sx after 5-7d bacterial will have little response to nasal decongestants and APAP empiric: amoxicillin, cephalosporin, TMP-SMX alternate: respiratory FQ, macrolide if PCN-resistant S. pneumo suspected: high dose amoxicillin and respiratory FQ

HIV pathophysiology

virus attacks CD4+ T cells and cells of the myeloid lineage (e.g. monocytes, macrophages , dendritic cells) reduction of the number of CD4 T helper and delayed-type hypersensitivity functions of the immune response virus remains latent in macrophages, dendritic cells, memory T cells, and hematopoietic stem cells HIV destroys these cells by increased permeability of the plasma membrane, syncytia formation, and induction of apoptosis

microbes

viruses, prions, bacteria, fungi, protists

Gastrointestinal and Viscerotropic Viral Diseases

visceral organs (blood, spleen, and liver) transmission: arthropods, body fluid, food/drink viruses are obligate intracellular parasites

diagnosis of warts

visual inspection with bright light biopsy when diagnosis is uncertain, pt immunocompromised, refractory lesions, persistent ulceration or bleeding, abnormal warts (pigmented, indurated, fixed)

clinical presentation chronic prostatitis

voiding difficulties (frequency, urgency, dysuria), low back pain, perineal and suprapubic discomfort boggy, enlarged prostate-soft and spongy, may indicate inflammation bacteriuria, bacteria in prostatic secretions

HIV genome

vpr-G2 cell cycle arrest and nuclear import of the preintegration complex nef-downregulation of cell surface CD4 and MHC class I vif-enhancement of virion release and CD4 degradation tat-trans-activator of HIV promoter rev-nuclear export of late, unspliced RNA gag-group specific antigen, makes core and capsid proteins pol-polymerase, protease, and integrase env-envelope, glycoproteins (gp41 and gp120) ltr-long terminal repeat sequences contain gene sequences used for binding different cellular transcription factors

potential sources of H5N1 exposure

water contaminated with duck feces, possible role of peri-domestic bird like pigeons, using untreated bird feces as fertilizer

*Nocardia asteroides

weakly gram +, partially acid-fast, branching thin filaments, fungi-like inhaled and produces lung abscesses and cavitations often misdiagnosed as TB, immunocompromised at highest risk blood-born dissemination is possible leading to abscesses in brain and elsewhere

Trichuris

whipworm A soil transmitted helminth prevalent in warm, humid conditions Can cause diarrhea, rectal prolapse and anemia in heavily-infected people

killed/inactivated vaccines

whole cell vaccines-less durable/strong immune response-requires boosters Hep A (Havrix, Vaqta, part of Twinrix), flu (most injections), polio (Ipol), rabies (Imovax, RabAvert)

live attenuated vaccines

whole cell-produce stronger/durable immune response-cold chain required CI in immunocompromised and pregnant e.g. Herpes Zoster (Shingrix, Zostavax), nasal flu (Flumist), MMR, rotavirus (RotaTeq, Rotarix), oral typhoid (Vivotif), varicella (Varivax), yellow fever (YF-Vax)

types of antigens in vaccines

whole cell: live (attenuated) or killed biomolecules (acellular): proteins, carbs, lipids, nucleic acids, conjugates (combo)

Bordatella pertussi

whooping cough 1. pertussis toxin-inhibits phagocytosis and binds to target cells 2. extracytoplasmic adenylate cyclase 3. filamentous hemagglutinin-allows binding to ciliated epithelial cells 4. tracheal cytotoxin

Norovirus transmission

winter peak (October-March), primarily direct person-to-person contact <10 viral particles, prolonged duration of viral shedding even after sx resolve stable in high chlorine and a range of temperatures (0-60C) repeated infections can occur, mostly in closed or semi-closed settings foodborne (most common in US) e.g. shell fish or salad from infected handlers can be airborne from a toilet flush containing vomit or stool can survive for weeks on hard surfaces, 12d on contaminated fabrics, and months to years in contaminated still water

Taenia solium

world-wide tapeworm from undercooked pork that contains cystercerci cystercicosis-less common, systemic disease where cysticerci encyst in muscles and in the brain-may lead to epilepsy

genital HPV RF in women

young, risky sexual behavior for woman or her partner, immunosupressed

HIV

+ RNA that brings its own reverse transcriptase so it can convert to DNA and incorporate in the host genome. Can lay dormant for years. When it leaves it can take part of the host genome with it. 5-8% of the human genome are viruses with the possibility of interspecies DNA (SIV)

retroviral synthesis

+ stranded RNA but do not undergo immediate translation. RNA-dep DNA polymerase transcribes into DNA which is placed in host genome e.g. HIV

viral replication

1. Adsorption and penetration 2 Uncoating of the virus (acidification primes it for uncoating?) 3. Synthesis and assembly of viral products 4. Release of virions from the host cell

*Trichinella life cycle

1. Adult Trichinella spiralis develop, invade intestinal wall of pig, and produce larvae that invade muscles 2. Larvae encyst in pig muscles (capsule 0.25-0.5mm in length) 3. Humans eat undercooked pork containing cysts 4. In human intestines, cyst walls are removed and adults develop. Adults produce larvae that encyst in muscles

lymphatic filariasis stages

1. Asymptomatic stage -There is internal damage to the lymphatics and kidneys 2. Acute stage - Filarial lymphangitis -Characterized by bouts of fever -heat, redness, pain, swelling and tenderness of the lymph nodes and ducts 3. Chronic stage -Usually results in elephantiasis as a result of chronic lymphoedema -There is a massive overgrowth of tissue resulting in severe deformities -The legs are often affected and result in inability to walk -The scrotum is often affected in men and the breasts and vulva in women

3 Main Clinical Presentations of systemic fungal infections

1. Asymptomatic-majority, may even be mild respiratory illness 2. Pneumonia-fever, cough, infiltrates on CXR -granulomas with calcifications can follow resolution (like TB) -usually mild, but a small percentage of severe PNA or chronic cavitary PNA 3. Disseminated-rare, but most common in immunocompromised -can cause meningitis, skin or bone lytic granulomas, lesions on other organs

Candida frequency in sepsis

1. Candida albicans (most common) 2. C. glabrata (2nd most common) a. C. tropicalis b. C. krusei 3. C parapsilosis (3rd most common) a. C. lusitaniae

*modes of transmission

1. Contact transmission -direct contact e.g. handshaking, kissing, sex, bites -indirect contact e.g. drinking glasses, toothbrushes, toys, punctures, droplets (sneezing or coughing within one meter) 2. Vehicle transmission -airborne e.g. dust particles -waterborne e.g. streams, swimming pools -foodborne e.g. poultry, seafood 3. Vector transmission -mechanical e.g. on insect bodies like flies and roaches -biological e.g. lice, mites, mosquitoes, ticks

PICORNA genera

1. Enterovirus-polioviruses 1-3, human coxsackivirus, human echovirus 2. Rhinovirus-human rhinoviruses 1-103 3. Hepatoviruses-human hep A virus 4. Parechoviruses-human parechoviruses 1-2 5. Aphtovirus-cattle, goats, pigs, sheep, and rarely humans 6. Cardioviruses-rodents and rarely humans

Four Clinical Manifestations of Salmonella

1. Gastroenteritis: nausea, vomiting, diarrhea 6 - 48 hours after ingestion Fever, abdominal cramping; self limited (3-7 days) 2. Sepsis/Bacteremia: occurs more rapidly than Typhoid fever and lacks typical rose spots and leukopenia 3. Typhoid Fever: fever begins 5-21 days after ingestion and persists 4-8 weeks in untreated patients (Salmonella typhi) -Rose spots (30%), hepatosplenomegaly (50%); most sx resolved by fourth week -death in 1-30%; intestinal perforation, abscesses, endocarditis; relapse in 10% 4. Asymptomatic carriage: 1-4%

antimicrobial therapy in 2016 sepsis guidelines

1. IV antimicrobials ASAP after recognition and within one hour 2. empiric broad-spectrum therapy to cover all likely pathogens 3. antimicrobial therapy be narrowed once pathogen identification and sensitivities are established and/or adequate clinical improvement 4. recommend against sustained systemic antimicrobial prophylaxis in patients with severe inflammatory states of noninfectious origin (e.g., severe pancreatitis, burn injury) 5. combination therapy should not be routinely used for ongoing treatment of most other serious infections, including bacteremia and sepsis without shock and neutropenic sepsis/bacteremia 6. If combination therapy is used for septic shock, we recommend de-escalation with d/c of combination therapy within the first few days 7. duration of 7-10d is adequate for most but longer courses are appropriate in patients who have a slow clinical response, undrainable foci of infection, bacteremia with S. aureus, some fungal and viral infections, or immunologic deficiencies, including neutropenia 8. daily measurement of procalcitonin can be used to support shortening the duration or d/c of empiric antibiotics in patients who initially appeared to have sepsis, but subsequently have limited clinical evidence of infection

*chain of infection-transmission

1. Infectious agent-bacteria, viruses, fungi, protozoa, helminths 2. Reservoir-people, environment, water 3. Portals of exit-excretions, secretions, droplets, skin 4. Means of transmission-direct contact/fomite, injection/ingestion, airborne/aerosols 5. Portal of entry-broken skin, mucous membrane, GI/respiratory/GU tract 6. Susceptible host-neonates, diabetics, immunosuppressed, cardiopulmonary disease AND IT STARTS ALL OVER

*Eukaryotic Microbe Parasites

1. Protozoa -Amoeba like Entamoeba histolytica, Naegleria, Acanthamoeba -Flagellates like Giardia lamblia, Trichomonas vaginalis, Trypanosoma, Leishmania -Ciliates like Balantidium coli -Sporozoa like Plasmodium, Cryptosporidium, Toxoplasma 2. Helminths -Roundworms like Ascaris lumbricoides, Enterobius vermicularis, Necatur americanus, Trichinella spiralis, Wucheraria bancrofti -Flatworms like Schistosoma (fluke), Taenia (tapeworm) 3. Arthropods -Insects -Arachnids

Echinococcus life cycle

1. adult tapeworm releases eggs which are excreted by definitive host e.g. wolf 2. intermediate host ingests eggs e.g. deer or human 3. eggs hatch and larva migrate to liver or lungs 4. larva develop into hydatid cysts 5. definitive host eats intermediate host e.g. deer, ingesting cysts 6. scoleces from cyst attach to intestine and grow into adults

HIV life cycle

1. binding of CD4 cell 2. fusion 3. reverse transcription 4. integration 5. replication 6. assembly 7. budding

gram stain

1. flood with crystal violet, wait 60 seconds, then wash off excess with water (all blue) 2. flood with iodine (all purple), wait 60 seconds, then wash off excess with water 3. decolorize with 95% alcohol (gram + will remain purple with crystal violet trapped in the wall) 4. counterstain with safranin (gram - will appear red) wait 30 seconds, then wash off excess with water All cocci are gram + except Neisseria and Moraxella Most pathogens are GNR

Toxoplasma gondii life cycle

1. imature oocyst shed in cat feces 2. mature oocyst develops by sporogony and contains two sporocysts, each with four infective sporozoites 3. sporozoites from ingested oocysts invade animal tissue and develop and bradyzoites within tissue cysts, or into tissue-invading tachyzoites 4. cat ingests bradyzoites in tissue cysts from animals e.g. mice

plasmodium life cycle

1. infected mosquiro bites; sporozoites migrate through bloodstream to liver of human 2. sporozites undergo schizogony in liver cell; merozoites are produces 3. merozoites released into bloodstream from liver may infect new RBCs 4. merozoite develops into ring stage in RBC 5. ring stage grows and divides, producing merozoites 6. merozoites released when RBC ruptures; some merozoites infect new RBC, and some develop into male and female gametocytes 7. mosquito bites infected human and ingests gamaetocytes 8. in mosquito digestive tract, gametocytes unite to form zygote 9. resulting sporozoites migrate to salivary glands of mosquito

*Examples of Encounters and Disease Prevention

1. inhalation-common cold-aerosol from infected person-avoid contact-hard 2. ingestion of fungus-present in soil-hard to avoid contact 3. ingestion of bacteria-water and food-sanitation to lower infecting dose 4. sexual contact-gonorrhea-change social behavior to avoid contact 5. wound-surgical ingection-opportunistic-aseptic techniques 6. insect bite-malaria-protozoan-insect control to avoid vector

methods of resistance

1. mutation-99.9% of the time mistakes are bad, but every now and then the mutation is good and makes the bacteria resistant. 2. conjugation-pilli can connect to a fellow bacteria and share genetic material that might be resistant

nitrate reduction

1. negative-no reduction 2. positive-partial reduction from NO3 to NO2-E. coli, Klebsiella, Proteus 3. positive-complete reduction from NO3 to N2-Pseudomonas

virus reproduction

1. replication of genetic material 2. proteins to make capsids 3. genetic material migrates into capsids 4. viruses bud off (take some of the host membrane with them) or lyse the cell (naked viruses released)

progression of sepsis

1. sepsis insult (endotoxins) 2. complement and macrophage activation 3. TNF, IL1, IL6 4. neutrophil activation and endothelial cell up-regulation 5. bradykinin (capillary leak), coagulation cascade (microthrombosis, ischemia), arachidonic metabolites and NO (vasodilation), oxygen radicals (tissue destruction)

hepatitis A

1.4 million people yearly worldwide Highest prevalence: Africa, South America, Middle East, and Southeast Asia no documented cases of chronic Hep A; death is rare (fulminant hepatitis) transmission: fecal-oral route, blood products rarely US outbreaks among people who use drugs, the homeless, and MSM RNA virus, acute, self-limiting, and confers lifelong immunity complete clinical recovery within 2mo in 60% of pts and virtually all patients w/in 6mo can be sick for a few weeks to a few months most recover with no lasting liver damage

bacteria and you

10% of our dry weight is bacteria There are 10-20x more bacterial cells than human cells in your body

Why did the military develop an attenuated vaccine for adenovirus stains 4 and 7?

10% of trainees develop this in the first few weeks of training

*culture interpretation

10-30% of people have natural E. coli colonization in urine culture, but don't treat until >100,000 CFU look for narrow spectrum that works best for the patient (dosing and administration)

ADENO

100+ serotypes, 52 of which infect humans; seven subgroups for humans A-G nonenveloped, dsDNA, 36,000 bp, can encode 30-40 genes, 70-90nm in size endemic, epidemic, and sporadic infections, many are subclinical live oral vaccine to prevent types 4 and 7 in military recruits

tissue invasive toxins in Clostridium perfringens

12+ lethal toxins named by Greek letters alpha (lecithinase) is the most lethal tissue destruction-gas gangrene

lymphatic filariasis

120 million in 80+ countried, 40 million disfigured or severely incapacitated 95% W. bancrofti, also Brugia malayi and Brugia timori adult worms live in afferent lymphatic vessels scrotal damage and massive swelling may occur elephantiasis in late stage disease trauma and secondary bacterial infection of affected tissues is common

Influenza A subtypes

16 H subtypes and 9 N subtypes In poultry, the viruses can mutate, usually within a few months, from then low pathogenic avian influenza (LPAI) form into the highly pathogenic form (HPAI). Only viruses of the H5 and H7 subtypes are known to cause the highly pathogenic (HPAI) form of the disease.

hepatitis C

170 million people infected, 4 million in the US, 17,000 new infections annually 1 of 30 baby boomers infected (those born between 1945 and 1965) -5 times greater incidence than other adults Genotypes 1, 2, 3, 4, 5, 6 (influences treatment options) up to 90% of HIV+ are also HCV co-infected Leading cause of liver transplantation acute infection-positive HCV RNA test and negative HCV antibody same regimens recommended for chronic and acute infection Chronic infection-HCV RNA present for 6 months or more

Kahoot-What is the minimum time needed for cultures to develop

18 hours

*Tick-borne borreliosis = Endemic Relapsing Fever

18 species of borreliae spread by soft ticks

Cause of death trends

1900s US-5 of the top 10 are infectious (pneumonia, TB, diarrhea/enteritis, liver disease, diphtheria) 2012 US-only 1 of the top 10 are infectious (influenza/pneumonia) 2015 low-income economies- 5 of the top 10 are infectious (lower respiratory infection, diarrhea, HIV/AIDS, TB, malaria)

History of HIV/AIDS

1981-Kaposi's Sarcoma and PCP in CA and NY-first young MSM, then injection drug users 1982-AIDS among hemophiliacs and Haitians and several European countries -The name "AIDS" - Acquired Immune Deficiency Syndrome - is created 1983-AIDS is reported among non-drug using women and children 1984-Scientists identify HIV (initially called HTLV-III or LAV) as the cause of AIDS -Western scientists become aware that AIDS is widespread in parts of Africa 1985-An HIV test is licensed for screening blood supplies -AIDS is found in China, and has therefore been seen in all regions of the world -Ryan White denied access to return to school 1987-Zidovudine (AZT) is the first drug approved for treating AIDS -ACT UP is formed to protest the $10,000 per year cost of AZT 1988-ACT UP protests-FDA "fast-track" of lifesaving drugs still in clinical trials 1991-AIDS is the leading cause of death in U.S. men aged 25-44 1993-Zidovudine (AZT) is shown to be of no benefit to those in the early stages of HIV infection but shown to reduce the risk of mother-to-child transmission of HIV 1995-Protease Inhibitors approved by the FDA 1996-Combination (HAART) is shown to be highly effective against HIV. 1997-Deaths from AIDS begin to decline in developed countries 2003-Prices of AIDS drugs start to become more affordable 2007-HIV treatment is shown to extend life by 24 years, at a cost of $618,900 2008-Of the 33 million people living with HIV only 3 million are getting treatment 2009-Polls show most Americans no longer consider AIDS a major problem however new infections continue to soar 2012-54% of people eligible for treatment are receiving ARVs

hepatitis B

2 billion people worldwide; 850,000 in US; 21,000 new in US; 500,000 to 700,000 deaths annually highest prevalence: Sub-Saharan Africa, Asia, Amazon, southern parts of Eastern and Central Europe transmission: exposure to blood or body fluids e.g. perinatal (most common in areas of high prevalence), percutaneous, semen, saliva and serum 2/3 do not know they are infected; about 50% of people with hep B in the U.S are Asian; leading cause of liver cancer

fungi types

2 main forms of fungi: yeast and mold yeast: unicellular, sometimes pseudohyphae, smooth colonies, prefers body temp mold: multicellular, branching hyphae, septate (cells separate and distinct) or nonseptate (lots of nuclei with no clear separation of cells), fuzzy colonies

number of people receiving antiretroviral treatment

2 million in 2005 21.7 million in 2017 30 million goal in 2020 33 million goal in 2030

HPV recurrence after treatment

2/3 reoccur within 6-12w of therapy, after 6mo most pts will have clearance if persistent after 3mo or poor response to tx, consider biopsy to exclude a premalignant or neoplastic condition esp in immunocompromised tx modality should be changed if pt has not improved substantially after 3 provider-administered treatments or if warts do not completely clear after 6 treatments

complement

3 main pathways: alternative, lectin, classical produce chemotactic and anaphylatoxic proteins (C3a, C5a) opsonization of bacteria (C3b) promotion of killing of gram - bacteria activation of B cells (C3d)

Diarrhea

3+ loose stools/24h, usually small intestine disease, fluid and electrolyte loss considered new episode after 2 full days w/o diarrhea acute diarrhea <2w: mild <=3 "the runs", moderate 4+ with local sx (cramps, nausea, tenesmus), severe 4+ with systemic sx (fevers, chills, dehydration) chronic/persistent >2w: not attributable to bacterial pathogen tenesmus=constant need to empty bowels (cramping, straining) diarrhea without blood and pus is usually enterotoxin production diarrhea with blood and pus is from invasive infection with mucosal destruction

Interpreting Negative Ebola RT-PCR Result

3+d since sx onset: ebola is unlikely <3d: interpret with caution, keep in isolation until a repeat test after 3d is negative

Tertiary (Late) Syphilis

30% untreated progress here within 1-20y; rare due to widespread abx use manifestations: gummatous lesions, cardiovascular syphilis

Cutaneous Fungal Infections - Dermatophytoses

30+ species of fungi can reside in the dead, horny layer of skin, hair, and nails secrete keratinase, which digests keratin leading to scaling of skin, loss of hair, and crumbling of nails causes: Microsporum, Trichophyton, and Epidermophyton

global HIV epidemic

36.9 million people living with HIV in 2017 1.8 million newly infected in 2017 (goal in 2020 <500000 and <200000 in 2030) 0.9 million HIV-related deaths in 2017 (goal in 2020 <500000 and <400000 in 2030) Up 14% from 2010 Down 18% new infections from 2010 Down 34% deaths annually from 2010 25.7 million African, 3.4 million Americas, 3.5 million South-East Asia, 2.3 million Europe, 1.5 million Western Pacific, 350000 Eastern Mediterranean 18.2 million women, 16.8 million, 1.8 million in 2017

Which adenovirus types are most likely to cause acute respiratory distress syndrome?

4 and 7

prostatitis tx

4-6w (drugs do not penetrate the prostate well) TMP-SMX, FQ, cephalosporins, beta lactam prophylaxis for recurrent infections: TMP-SMX, FQ, nitrofurantoin

IgM

5-10% Ig, 5d half-life, first Ab produced in response to an antigenic challenge major component of rheumatoid factors (autoantibodies)

IgA

5-15% of total Ig, 6d half-life; role in immune function of mucus membranes present in breastmilk, tears, saliva, sweat, and other secretions

ingestion/intestinal anthrax

50% fatal, rare in humans; N/V/D(severe) abdominal pain, vomiting blood

adenoviridae diversity

57 types in humans in 7 species of adenovirus A to G from mild respiratory infections in young children (common cold) to life-threatening multi-organ disease in people with weakened immune system different serotypes associated with location and even severity of infection

when to use abx in AOM

6mo-2yo when sx are not severe: just watchful waiting and APAP or IBU for pain give abx in severe illness, when underlying conditions are present, or no improvement in 48-72h (some say 24h)-amoxicillin, Augmentin, cefuroxime (Ceftin), cefpodoxime (Vantin), Omnicef, Bactrim, erythromycin-sulfisoxazole 5d of therapy in children >2yo likely just as effective as 10d-compliance is better, decreased SE, decreased cost, decreased bacterial-selective pressure

HIV testing and care continuum

75% aware of HIV status 59% on treatment 47% viral load suppression

E. coli

80-90% of uncomplicated UTI but <50% of complicated UTI GNR, facultative anaerobe, flagella, may acquire pili (stick to wall and not be peed out), encapsulated, lactose-fermenting.

IgG

85% of Ig in adults, 23d half-life requires T-cell help for production produced more rapidly with subsequent antigenic challenges

facultative pathogenicity of Entamoeba histolytica

85-90% of infected individuals are asymptomatic ~10% of the symptomatic will develop severe invasive disease

cutaneous (inoculation) anthrax

95% of anthrax infections; spores gain access through skin breaks often in sheep shearers; black necrotic ulcer forms in 1-3d

bacteroides

99% of flora of GIT, non-spore forming, anaerobic GNR No lipid A in outer cell membrane (No endotoxin) Low virulence, major opportunistic pathogen (affecting damage to intestines) Can infect every part of your body

IgD

<1% of Ig, 3d half-life, produced with IgM, activates B-cell growth

IgE

<1% of immunoglobulins with 2.5 day half-life bound to FcRs on mast cells, allergic and parasitic response anaphylactic sensitivity (Type 1)

hepatitis B vaccine

<19yo, people at risk for infection by sexual or blood exposure, dialysis pts, DM pts 19-59yo, international travelers to countries where it's common, hepatitis C, chronic liver disease, HIV, jail or prison single antigen: Recombivax HB and Engeric-B combination: Comvax and Pediarix in peds, Twinrix in adults (0, 1, and 6mo)

hookworm

>1200 million infections each year, 100 million are symptomatic Necator americanus-predominant in subSaharan Africa, south Asia, Pacific Ancylostoma duodenale-predominant in S. Europe, N. Africa, W. Asia, N. China, Japan, W. US; ingests 4-5x the amount of blood as N. americanus hookworms moce several times a day to different attachment sites in the upper intestinal mucosa to ingest blood secrete anticoagulant which causes the old attachment sites to continue to bleed which can lead to chronic hemorrhage in a child, the continued daily loss of 10mL can lead to severe anemia

inhalation anthrax

>90% fatal; incubates up to 6w spore size is 1-5 microns (reach deep into alveolar injection by macrophages) commonly fatal due to toxins produced in lympth nodes flu-like sx progress to respiratory arrest shock

Choleragen toxin

A subunit (*A*ction) B subunits (5 subunits attached to the A subunit) - *B*inding subunits -Binds to GM1 ganglioside on surface of intestinal membrane -Allow entry of A subunit Subunit A produces a sustained release of cyclic adenosine monophosphate (cAMP). -Massive secretion of water -Secretion of Na and Cl ions and prevention of their reabsorption -NaCl has osmotic pull of other electrolyte (Fluid, bicarbonate, potassium etc)

toxocara

A world-wide infection of dogs and cats Human infection occurs when embryonated eggs are ingested from dog or cat feces It is common in children and can cause visceral larva migrans (VLM)

influenza types

A-seasonal, humans, mammals, birds, causes all flu pandemics B-seasonal, humans and seals C-few or no sx, humans, pigs, and dogs D-pigs and cattle

lower respiratory tract infections

AECB, pneumonia, CAP, HAP, HCAP (healthcare associated pneumonia), VAP, aspiration pneumonia

Kahoot-Which is caused by + RNA virus?

AIDS

What is the difference between an HIV positive or AIDS diagnosis?

AIDS diagnosis: CD4 < 200 OR HIV infection + diagnosis of AIDS defining condition (e.g. Kaposi sarcoma, pneumocystis pneumonia (PCP), toxic plasmosis)

*Tinea Cruris

AKA "jock itch" itchy red patches on groin and scrotum that should be kept cool and dry

Mononucleosis

AKA "kissing disease", spread through saliva herpes virus called EBV, dsDNA, enveloped, icosahedral *ultimate B-lymphocyte parasite (immortalized B cells)* associated with endemic Burkitt lymphoma, Hodgkin disease, and nasopharyngeal carcinoma infectious mono as a result of overactive immune response (war between EBV-infected B cells and protective T cells) which leads to an increase in lymphocytosis (mononuclear cells) possible jaundice, splenomegaly, chronic fatigue, sore throat, aching muscles, sleep disturbances, swollen lymph nodes 70% of the population is infected by age 30 and 90% of infected people will intermittently shed the virus for life malaria is a cofactor in the progression of chronic or latent EBV susceptibility in immunocompromised, transplant pts, HIV rarely fatal in healthy people no effective tx or vaccine; body rash as a result of ampicillin 3-4 weeks

*Tinea Unguium

AKA "onychomycosis" Leaves nails thickened, discolored, and brittle

Tinea Corporis

AKA "ring worm" Fungi spread outward creating a red ring (active inflammation) with a healing center

yellow fever

AKA "yellow jack", Walter Reed in Panama, Togaviridae, enveloped, RNA flavivirus, zoonotic (monkeys), and Aedes aegypti mosquito, (sub)tropical high fever, jaundice, bleeding gums, bloody stoole, vomit blood supportive treatment and preventative vaccine

erythema infectiosum

AKA *fifth disease-characterized by slapped-cheek appearance* and lacy exanthem (widespread rash that begins on face, then extremities, then trunk) cause: erythrovirus B19 (paraviridae family-ssDNA); sx management only

gas gangrene

AKA Clostridial myonecrosis from C. perfringens (GPR) very rare, life-threatening, especially after trauma that causes loss of blood flow increased pain and swelling around injury followed by dark red to purple skin, foul-smelling drainage, and crepitation (crackling sound from underlying gas) dead tissue must be removed and antitoxin, PCN, and clindamycin administered

rubella

AKA German measles, or three day measles, very rare, contagious, rubivirus, +ssRNA low grade fever, sore throat, swollen lymph nodes, rash that starts on the face and spreads over the body and *lasts around 3 days* may cause miscarriage and serious birth defects supportive therapy and MMR vaccine given at 12-15mo and second dose at 4-6y

beaver fever

AKA Giardia lamblia The risk of acquiring the infection from cats and dogs is very small. Humans are normally infected by a different strain than the ones that plague our pets

acid fast

AKA Kinyoun-Mycobacterium/TB and select other atypicals 1. flood with carholfuschin 2. heat 3. decolorize with acid-alcohol (acid-fast cells retain dye) 4. counterstain with methylene blue (non acid-fast cells blue)

Legionella pneumophila

AKA Legionaire's disease-cooling unit at a hotel was infected and killed several members of the American Legion GNR-very poor staining distributed across all age groups, waterborne reservoir, airborne transmission incubation: 2-10d, communacability: person-person unconfirmed DOC-azithromycin or FQ

roseola

AKA Sixth Disease-mild viral illness characterized by sudden high fever and a rash that develops as the fever resolves cause: HHV6 (human herpesvirus 6), dsDNA *high fever that lasts 3-5d followed by a rash typically only seen <3yo* supportive therapy only roseola as a child-more susceptible to HIV tepid bath-lukewarm water to bring the temp down

Paracoccidioidoes brasilensis

AKA South American blastomycosis, paracoccidiodomycosis, dimorphic, systemic soil fungus inhaled into oro-nasal mucosa (spleen, liver, intestine, skin later) DOC: amphotericin B + sulfas + azole multiple, narrow base, budding yeast cells resembled "steering wheels"

lecithinase

AKA alpha toxin from C. perfringens, enterotoxin, lyses all blood cells (RBCs, WBCs, platelets, endothelial cells) to cause massive hemolysis, vascular permeability and bleeding tissue destruction (myonecrosis-very fatal), hepatic toxicity, and myocardial dysfx (bradycardia, hypoTN) thin black exudate of liquified muscle ferment carbohydrate-gas forms bubbles under the skin (gas gangrene)

woolsorter's disease

AKA anthrax

Viral Meningitis

AKA aseptic meningitis cause: entero-Cocksackie, Echovirus, influenzae A&B, CMV, varicella, HSV dx-based on LP to obtain CSF-PCR test sx-similar to bacterial meningitis history of recent viral infection common tx: supportive care as viral meningitis is usually self limiting

*Tinea Pedis

AKA athletes foot, typically peeling of skin that starts between the toes infection requires warmth and moisture

Schistosomiasis

AKA bilharzia S. haematobium - Africa and middle east (most prevalent) S. mansoni - Africa and Latin America S. japonicum - Pacific region infective cercariae from snails of genera Bulinus, Biomphalaria, Oncomelania, penetrate skin in infected fresh water, adult worms live in veins and drain the urinary system (S. haematobium) or mesenteric blood vessels (S. mansoni, S. japonicium) and release eggs in urine or feces, eggs develop into miracidia which infect snails

stye

AKA hordeolum-bacteria in oil glands in the eye lids-usually Staph aureus develop a few days and may drain and heal on their own red, swollen bump like a pimp, tender to the touch Stye, the medicine, is almost useless; hygiene works better apply warm, wet cloth for 10min QID; do NOT attempt to squeeze no contact lenses or eye makeup until its healed

RSV

AKA human orthopneumovirus, caused by paramyxoviridae severe respiratory infections leading to pneumonia <1yo (~100,000/year in US) most prevalent cause of respiratory infection in children <6mo in adults with chronic heart and lung disease or as a complication from other infections (flu, chickenpox), viral pneumonia may develop following flu-like sx the pt develops fever (~102F), breathing difficulty, cough, rhinitis, wheezing, otitis, croup (seal-barking cough), frothy blood-tinged sputum diagnosis from process of elimination infects URT and produces giant multinucleate cells epithelia of nose and eye as portal of entry; replicates in nasopharynx tx: synagis, a monoclonal antibody that blocks attachment, ribavirin

fungal keratitis

AKA keratomycosis-slow (weeks) progression of corneal inflammation whose epithelium may be intact or ulcerated, cause: Fusarium, Candida, Aspergillus ulcerated areas-usually feathery edges, heaped margins, and satellite lesions blurred vision, pain, photophobia DOC topical antifungal, nafamycin or amphotericin B eye drops

bacterial cell wall

AKA peptidoglycan layer repeating disaccharides with 4 aa extending from each disaccharide each peptidoglycan covalently binds aa from neighboring chains *transpeptidase is the enzyme responsible for creating these linkages* penicillin binds and inhibits this enzyme, therefore it is also called "penicillin binding protein" (PBP)

tinea versicolor

AKA pityriasis versicolor by M. furfur-lipophilic yeast-like organism common superficial infection seen worldwide (60%) irregular, well demarcated patches of discoloration and scaling of skin ("chalky appearance"), 3-8 microns in diameter scrapings reveal clusters of spherical yeast-like cells that may be mixed with short, branched hyphae "spaghetti and meat balls" cells show a polar bud formation with a "lip" or collarette around the point of bud initiation on the parent cell standard media contains olive oil-M. furfur grows cream or tan colonies mostly asymptomatic with mild pruritis in severe cases

Tularemia

AKA rabbit fever/deer-fly fever (inhalation of organisms while skinning rabbits) Francisella tularensis, found in ground squirrels in Tulare county in CA small gram - coccobacillus, non-motile, thin lipid capsule, strictly aerobic, facultative intracellular (esp macrophages-inhibit phagosome-lysosome fusion, and replicate in macrophage cytosol) non-specific skin lesions-well demarcated hole with black base (buboes ulceroglandular) 75% pneumonic: high fever, sore throat, pneumonia, pleuritis, septic shock, and meningitis potential use as a biowarfare agent, aerosol kill rate exceeds 30% DOC-aminoglycosides (streptomycin, gentamycin)

measles

AKA rubeola, extremely rare, highly contagious, cause: morbillivirus (+ssRNA) caused by paramyxoviridae ssRNA replicates in respiratory mucus membranes and conjunctival membranes incubation 2 weeks prior to characteristic rash prodrome: flu-like illness, conjunctivitis, eyelid swelling, photophobia, fever (~105F), hacking cough, rhinitis, and malaise Koplik's spots 2d prior to rash-small, red-based lesions with blue-white centers on buccal mucosa very contagious; aerosol transmission; spread by crowded conditions, malnutrition, and inadequate health care (lack of vaccination-attenuated MMR) rash-red macropapular (flat-to-bumpy) spreads from head to feet and disappears in the same sequence diagnosis: age, exposure, and time of year passive immunity can be transferred from mother to child and protect children under 5 or 6mo of age tx: supportive therapy, vit A, measles Ab and *ribavirin*

RMSF

AKA spotted fever rickettsiosis-bacterial disease spread through the bite of an infected tick with Rickettsia rickettsii dx: presentation, serological testing (latex agglutination, fluorescent Ab stains) tx: doxycycline for adults and children; chloramphenicol if pregnant (chance of grey baby syndrome better than teratogenicity) male ticks infect females during mating and it is transferred to the forming eggs ticks can live up to 4 years without feeding

Necrotizing Fasciitis

AKA streptococcal gangrene-very rare, rapidly progressing inflammatory infection of the fascia with secondary necrosis of subcutaneous tissue cause: *S. pyogenes (GAS)*, S. aureus, C. perfringens, B. fragilis flu-like sx followed by *severe pain*, redness and swelling at infection site, followed by systemic sx tx: surgical removal of infectious tissue and appropriate abx (usually PCN)

Bordatella pertussis

AKA whooping cough, GNR fever, malaise, severe paroxysms of rapid-fire coughs with characteristic "whoop" and rope-like strands of mucus. increased WBC and marked lymphocytosis pertussin toxin-subunit B binds to target cell and subunit A activates G proteins which cause an outpouring of cAMP that impairs chemotaxis and generation of H2O2/superoxide filamentous hemagglutinin on pili aid in attachment (never enters) to bronchial epithelial cells where it releases exotoxins trachial cytotoxin-destroys ciliated epithelial cells and impairs clearance which probably causes violent cough frequent cause of unexplained cough in adolescents and adults Over half are in children 0-2yo DOC-erythromycin

who to treat for HIV

ART for all HIV-infected regardless of CD4 count to reduce m&m and prevent transmission. ART may be deferred because of clinical and/or psychosocial factors, but the therapy should be initiated ASAP. Should commit to tx and understand the benefits, risk, and importance of ART.

Virulence

Ability to cause disease or death - degree of pathogenicity or case fatality due to the pathogen Number of deaths/number with disease x 100

Infectivity

Ability to invade a host Number infected/No. susceptible x 100

Asymptomatic Bacteriuria

Absence of urinary symptoms (females, elderly, or pregnant) Urine cx reveals >100,000 CFU/ml bacteria Need for treatment is controversial unless pregnant -If untreated: prematurity, low birth weight, stillbirth -Amoxicillin, amoxicillin-clavulanate, cephalexin x7days

HAP/HCAP/VAP causes

Acinetobacter, P. aeruginosa, S. aureus (MRSA), K. pneumoniae (ESBL), E. coli, S. pneumoniae, H. influenzae, Enterobacter, Serratia

DNA virus synthesis and assembly

Act very similar to our own DNA Use host machinery in the nucleus to be transcribed into mRNA mRNA is then spliced, processed and sent to the cytoplasm where translation occurs

fungi-like bacteria

Actinomyces Israelii and Nocardia asteroides

cestodes

Adult tapeworms are found in the intestine of their host They have a head (scolex) with sucking organs, a segmented body but no alimentary canal Each body segment is hermaphrodite e.g. Taenia (tapeworm), echinococcus

GNR examples

Aerobe: Pseudomonas Anaerobe: Bacteroides Microaerophilic: Campylobacter Almost everything else is a facultative anaerobe

GPR examples

Aerobes or facultative anaerobe: Corynebacterium, Listeria, Lactobacillus, Nocardia, Mycobacterium, Bacillus Anaerobe: Actinomyces, Clostridium

*bacterial identification tools

Agars - used to cultivate select bacteria Combines growth characteristics, gram stain, and biochemical tests

*Factors influencing host of disease transmission

Age Sex Genotype Behaviour Nutritional status Health status

*Factors Influencing Disease Transmission

Agent Environment Host

*Classification of Infectious Diseases

Agent and Host Disease incidence Portal of entry Source Symptom Disease course Site of infection Virulence factors

Chikungunya

Alphavirus genus, first in Tanazia, name in Makonde means "that which bends up" severe febrile arthralgia from bites from infected mosquitoes

Gastroenteritis

An inflammatory syndrome characterized by gastrointestinal symptoms including nausea, vomiting, diarrhea and abdominal discomfort (usually in the stomach and small intestines)

dx cutaneous mycosis

Anatomical site infected Type of lesion Examination with a Woods lamp Microscopic examination of KOH-treated skin scales from the infected area Culture of the organism In a differential diagnosis you must consider other etiologies such as: Leprosy Secondary syphilis Pityriasis rosea Psoriasis Nummular eczema Lichen planus Alopecia areata Trichotillomania Dyshidrosis Contact dermatitis. Moral of the story.....refer the patient to their primary care provider if in doubt at all!!

5-flucytosine

Ancobon, only available antimetabolite, activated by deamination within fungal cells to 5-FU (inhibits thymidylate synthetase) inhibits fungal protein synthesis by replacing uracil with 5-FU in fungal RNA resistance common, used in combo with other antifungals broad range only in the tx of serious infection with Candida and/or Cryptococcus mammalian cells lack cytosine deaminase

meningitis tx

Antibiotics -Empiric treatment prior to pathogen identification -De-escalate to targeted therapy when pathogen identified -Antibiotics must have good CSF penetration to be of benefit and should be bactericidal Steroids -Conflicting data on benefit, but thought to reduce neurologic damage due to inflammation -May reduce antibiotic penetration into CSF Supportive Care -Fluids -Electrolytes -Antipyretics -Analgesics NOT ON THE EXAM

*Adaptive Immune Response

Antigen specific response The antigen must first be processed and recognized, then immune cells specifically designed to fight that antigen are created Has a memory component to make future responses more efficient

Aspergillus

Aspergillosis Mostly pulmonary infections Allergenic (Allergic sinusitis and allergic bronchopulmonary aspergillosis) Infections common in birds

*human H5N1

Azerbaijan, Cambodia, China, Egypt, Indonesia, Iraq, Thailand, Turkey, Vietnam more than half of the humans infected have died if human-to-human transmission becomes possible we may have a pandemic

*Kahoot-whooping cough caused by

B. pertussis

virus pretalk

BIOSIS-How do you decide if something is living?-DNA, reproduce, motility, metabolism, maintains homeostasis, responds to stimuli, growth virus-capsid, genetic material get into cells via endocytosis, fusion (enveloped by last host cell), and bacteriophage (inject the virus into the bacteria)

BCG

Bacilli Calmette-Guerin-live attenuated M. bovis-effectiveness wears off protects against meningitis and disseminated TB in children but does not prevent primary infection or reactivation of latent infection not effective against pulmonary TB

only bacterium with total protein capsule

Bacillus anthracis

bacterial endophthalmitis

Bacillus cereus (trauma with introduction of contaminated soil), Pseudomonas, Staphylococci, Propionibacterium, Corynebacterium intravitreal abx usually needed e.g. vanc 1mg+ceftazidime 2.25mg-may need to repeat in a few days, systemic abx recommended in endogenous infection

*bacterial oxygen utilization

Bacteria possess 3 possible enzymes to break down oxygen: catalase, peroxidase, superoxide dismutase

Gram - Obligate Anaerobes

Bacteroides

gram negative anaerobe

Bacteroides fragilis

Virus Adsorption and Penetration

Binds host cell through a specific interaction between a capsid protein and a host cell membrane receptor Internalization through 2 possible mechanisms 1. Endocytosis 2. Fusion on the viral envelope with the host cell membrane

cultures in sepsis

Blood cultures (+) in only 1/3 of cases In 1/3 of cases, cultures from all sites (blood, sputum, urine, etc.) are negative

Lyme disease

Borrelia burgdorferi/garinii/afzelii, large spirochete, diderm reservoir: white-footed mice, white-tailed deer and ticks (deer tick attached 24+h) leading cause of vector-borne disease in the US W. Burgdorfer discovered agent, disease discovered in Lyme, Connecticut sx: syphilis-like in three stages localized: flu-like sx and swollen lymph nodes, bulls eye rash after 10d, lasts 4w early disseminated: systemic spread over weeks-skin, heart, nervous system, joints late stage: arthritis, nerve disorders, rarely fatal DOC doxycycline (tooth staining and enamel loss in children) or amoxicillin

Spirochetes anaerobe

Borrelia, Treponema

Relapse Fever

Borrelia-spirochetes, microaerophilic (need oxygens in small amounts), diderm no gram staining, stain with Giemsa or Wright stain axia flagella that runs the length of the bacterium acute infection; incubation 2-14d (usually 6) recurring febrile episoders-antigenic variation constant spirochaetemia that worsens during febrile stages DOC-doxycycline, erythromycin

*CRP

C-reactive protein inflammation indicator

Kahoot-gram + anaerobe

C. Diff

*Kahoot-bacteria that causes uncontrolled spasms

C. tetani

Giemsa

CBC for blood-borne pathogens

HIV coreceptors

CCR5 and CXCR4 present on CD4+ cells most drugs enter through CCR5 CCR5 is a target of ART kind of last line because some enter through CXCR4 as well

ebola laboratories

CDC has developed interim guidance for U.S. laboratory workers and other healthcare personnel who collect or handle specimens This guidance includes information about the appropriate steps for collecting, transporting, and testing specimens from patients who are suspected to be infected with Ebola Specimens should NOT be shipped to CDC without consultation with CDC and local/state health departments

*meninges

CNS protected from blunt or penetrating trauma by skull and vertebrae three meninges: dura mater, arachnoid mater, pia mater subarachnoid space-conduit for CSF between arachnoid and pia

*body fluid analysis

CSF: WBC, glucose, protein, culture, gram stain UA: WBC, RBC, multiple reagent strip (pH, protein, ketones, blood, bilirubin, leukocytes, nitrite, specific gravity) synovial, peritoneal, etc.: WBC, albumin, protein, culture, gram stain

*Positive (+) Stranded RNA Viruses

Calcified emperor Pico is wearing his Crown and Toga and is eating Flavorful grapes from a Retro bowl-Calici, Pico, Corona, Toga, Flavi, Retroviridae immediately translated by host ribosomes into proteins equivalent to preformed mRNA utilize RNA-dep RNA polymerase to make - stranded templates for replication

*signs of inflammation

Calor (Heat) Dolor (Pain) Rubor (Redness) Tumor (Swelling)

Indirect ELISA Interpretation

Can be used to differentiate a recent (acute) infection from previous exposure using IgM, IgG, and titers.

Pneumocystis jiroveci

Can become part of the normal flora of the lung (usually sterile environment) for the immunocompromised e.g. CF

Cutaneous Fungal Infections - Candida

Candida albicans can infect mouth (thrush), groin (diaper rash), vagina (Candida vaginitis), and cause opportunistic systemic infections

lobomycosis

Caused by Lacazia loboi (Hydrophilic fungus) : exists only as yeast cells. Involves exposed parts Presence of macule, papule, keloid, verrucous, nodular lesions or plaques & tumors. Lesions are painless with slight pruritis

toxoplasmosis

Caused by toxoplasmosis gondii -Protozoal parasite Diagnosis -Detection of toxoplasma antibodies Clinically affects -HIV/AIDS and immunocompromised patients -Pregnant patients Transmission -Can only occur via ingestion, mother to baby, or through organ transplantation -Cats can shed toxoplasma in their feces

non-culture-based diagnosis

Clinical signs and symptoms compatible with an infectious process Detect pathogen-specific antibodies in patient's serum Detect pathogen antigens/nucleic acids in specimen General/non-specific tests (CBC/Flow/Chemistry/UA)

Gram + Obligate Anaerobes

Clostridium

gram positive anaerobe

Clostridium

botulism

Clostridium botulinum-GPR, anaerobe neuroaralytic illness characterized by symmetric, descending flaccid paralysis (always begins with the cranial nerves)

more widely spread than any other pathogen

Clostridium perfringens

*bacterial morphology

Cocci: spherical Bacilli: rods. Short bacilli are called coccobacilli Spiral forms Pleomorphic: lacking a distinct shape

diphtheria

Corynebacterium diphtheria, GPR, non-spore forming club shaped, variable lengths, shapes resemble palisades and chinese letters acute disease involving mucus membranes of URT exotoxin kills throat tissue and forms assymetrical pseudomembrane children may asphyxiate on tissue "bull neck" from swollen nodes and neck occurrence: children <15yo; transmission: contact with pt or soiled articles incubation: 2-5d, communacability: 2w DOC: diphtheria equine antitoxin + penicillin or erythromycin

CJD

Creutzfeldt-Jakob Disease etiology unknown, ~1 case per million population S/Sx include Dementia and other early neurological signs Median age at death - 68 years Death typically occurs within 1 year of symptom onset

criteria for influenza pandemic

Criteria for a pandemic: Novel strain that is not recognized by the human immune system Causes increased sickness and death Sustained person-to-person transmission Concern that virus will change to increase person-to-person transmission -So far such spread has been limited, not sustained

Kahoot-encapsulated fungus

Cryptococcus neoformans

Cryptococcal meningitis

Cryptococcus neoformans-basidiomycetous, budding, encapsulated yeast found in soil and acquired by inhalation of spores; dx with india ink stain common in immunocompromised-HIV, chronic steroids, transplant, malignancy sx (days or months): fever, HA, lethargy, personality changes, memory loss

cell structure of Entamoeba histolytica

Cysts: 10-20 um in diameter -Cysts: 4 nuclei -Peripheral chromatin: Evenly distributed Trophozoites -Diameter: 15-20 um -Spherical or oval shaped -Thin cell membrane -Prominent nuclear border -Central karyosome -Vacuole -Movement towards colon: via finger-like pseudopods -Ingest Erythrocytes and absorb nutrients to survive -Some trophozoites transform into cysts

viral serotypes of DHF

DEN1-4, antigenically distinct and no cross protective immunity co-circulation of various serotypes cause severe disease-affects herd immunity to one serotype antibody-dep enhancement, all transmitted by Aedes aegypti mosquitoes

Chemoprophylaxis of TB

DOC isoniazid; only for high risk groups

influenza DOC

DOC-neuraminidase inhibitors oseltamivir (Tamiflu), zanamivir (Relenza) are effective against H1N1 swine flu, but amantadine and rimantadine are not M2 protein inhibitors-rimantidine, amantadine-synthetic tricyclic amine used for prophylaxis for influenza A treatment relieves sx, aspirin CI (Reye's syndrome)

tx and prophylaxis sporotrichosis

DOC-saturated solution of KI oral ketoconazole or itraconazole ampho B-disseminated and CNS disease

tx trichomoniasis

DOC: metronidazole (only tx in US) for both partners 90% cure rate; SE: N/V, metallic taste, GI upset alternative: tinidazole-firstline if refractory to metronidazole

Treatment, Prevention and Control B. coli

DOC: tetracycline; alternative: iodoquinol and metronidazole prevention: careful monitoring of pig feces and appropriate hygiene

*antibiotics that target folic acid synthesis (bacterial DNA)

Dapsone, sulfonamides Don't need to know for exam 1

*site of infection

Determined by -Type of pathogen - capacity to invade the body or certain tissues -The portal of entry -Competence of host's immunologic defense system

lymphatic filariasis tx, prevention and control

Diethylcarbamazine (DEC) rapidly kills microfilariae and will kill adult worms if given in full dosage over 3 weeks Release of antigens from dying microfilaria causes allergic-type reactions - add an antihistamine and aspirin to treatment regimen Other treatment options are -ivermectin -combination of DEC and albendazole Rapid diagnosis and treatment of infected individuals Mass drug administration to at risk communities Vector control: eliminate mosquito breeding sites through improved sanitation and enviromental management Personal protection against mosquito bites by insecticides, bed nets and repellents

fluconazole

Diflucan, IV or PO, high CSF concentration, 90% excreted unchanged, t1/2=25h Candidiasis, Coccoidosis (meningitis)

Corynebacterium diphtheria

Diphtheria toxin inhibits cellular protein synthesis and causes myocarditis, peripheral nerve palsies, and CNS effects

three types of ELISA

Direct ELISA - probes for antigen w/ a single labeled antibody -Tests for antibodies to a specific antigen (simplest form) Indirect ELISA - probes for antibodies to an antigen...labeled antibody binds to an unlabeled antibody -Ex. HIV, lyme disease, etc Sandwich ELISA - Antigen is "sandwiched" between two antibodies...MOST COMMON -"EPT" pregnancy tests

*H5N1 challenges

Disposal Occupational health Developing new wild bird surveillance program Hunting? Public perception - panic?

Diagnosis of Dermatophyte Infections

Dissolve skin scrapings in KOH, which digests keratin revealing branched hyphae on microscopic examination Wood's light - Certain species of Microsporum will fluoresce a brilliant green under UV light at a wavelength of 365 nm

virus history

Dmitry Ivanovsky - Used filters to show that sap from a diseased tobacco plant remained infectious to healthy plants after being filtered (1892) Martinus Beijerinck - Called the filtered infectious substance a "virus"

diagnosis and treatment of polio

Dr. Jonas Salk vaccine (IPV) is a formalin-inactivated virus used in injections over several months with boosters every five years Albert Sabin later introduced oral (OPV) but IPV is preferred currently no effective tx other than palliative care

How is adenovirus transmitted?

Droplets, fecal-oral, water-borne, fomites

Kahoot-Which is a nitrate + bacteria?

E. coli, Klebsiella, Proteus, Pseudomonas (complete)

Encapsulated Pathogens Removed by the Spleen

E. coli, S. pneumoniae. Salmonella, K. pneumoniae, H. influenza, P. aeruginosa, N. meningitides, Bacteroides fragilis, Cryptococcus neoformans (yeast)

nosocomial UTI

E. coli, other GNR that are aerobic (K. pneumoniae, Proteus mirabilis, Morganella morganii, Serratia, Citrobacter, Pseudomonas), Enterococcus, Candida

amoeba

E. histolytica-amoebic dysentery Naegleria-primary amoebic meningoencephalitis Acanthamoeba-contact lens contaminant no defined shape, pseudopodia, water sources, few cause disease

hepatitis C serological tests

EIA or CIA screening assay for anti-HCV, verification by NAT for HCV RNA (active) HCV genotyping for predicting tx response and determining duration of therapy

*rapid tests

ELISAs and agglutination tests Strep throat, C. difficile, O157H7, select meningitis organisms

fungi cell components

ER, nucleus, Golgi apparatus, mitochondira, cell membrane, cell wall, ribosomes cell membrane contains ergosterol-big target of antifungals cell wall contains mannoproteins, glucans, and chitin

nosocomial PNA

Enterobacter, Klebsiella, Pseudomonas, S. aureus (consider MRSA)

Which UTI-causing bug is in chains?

Enterococcus

detection and screening for HIV

Enzyme-linked immunosorbent assay (ELISA) -4th generation ELISA tests detect antibodies against HIV-1 and HIV-2 also p24 antigen reducing the detection window period -Can use blood, oral fluid, urine -Rapid HIV Tests available with results under 30 minutes Antigen testing will catch it quite early in the disease. There is a lag time before you make antibodies. OTC Oraquick doesn't really work for the first 3 months.

ECM

Erythema chronicum migrans "bulls eye rash"

Gastrointestinal Bacterial Pathogens

Exogenous: exposure to bacteria from external sources Endogenous: disruption of normal flora by broad spectrum antibiotic treatment -Diet, stress, changes in the host's response to the flora, invasion of other tissues

biofilms

Extracellular polysaccharide network that forms a mechanical scaffold around bacteria that allows bacteria to adhere to prosthetic devices and protects them from antibiotics and the immune system e.g. Catheters, Prosthetic heart valves

Antimicrobial Susceptibility of N. gonorrhoeae

FQ resistance is widely disseminated 25% are resistant to PCN, tetracycline, or both sporadic cases of decreased susceptibility to ceftriaxone and cefixime

*evasive factor

Factor produced by microbes to evade host defenses 1. gain superficial entry 2. gain entry into internal environment 3. evading antibody-mediated immunity 4. alternative life cycle

HIV epidemiology

Factors contributing to spread of HIV -Travel -Blood Transfusions (before we had screenings) -Drug use

potential vaccine advances on the horizon

Faster production: -Example: Use of tobacco-based production of ZmappTM for Ebola New/improved vaccines: -"Universal" flu vaccine -New cancer vaccines -New vaccines for food allergies

trichrome

Fecal parasite concentrate

West Nile virus

Flaviviridae family, main vector-Culex pipiens humans are "dead end" hosts as the virus cannot spread back to the vector because consistent viremia is not maintained but can be spread through blood transfusions severe neuroinvasive human disease-highly virulent to horses and corvid birds *incubation 5-10d* mostly benign but serious meningitis and encephalitis or hemorrhagic disease can occur in 1% of cases, mostly elderly 20% develop West Nile Fever-HA, body ache, skin rash, swollen lymh glands acute flaccid paralysis in utero and breast milk transmission is rare dx: PCR, serology-IgM in CSF or serum on acute presentation tx: supportive care, ribavirin lineage 1-clinical human disease, lineage 2-African animals

*sty

Folliculitis at the base of the eye lid

botulism transmission

Foodborne-illness in a few hours to days e.g. improper home canned foods Infant botulism Wound botulism-rare Iatrogenic-overdose injected botulinum toxin for cosmetic or medical purposes

fecal-oral protozoa

G. lamblia-worldwide, lives in small intestine and results in malabsorption E. histolytica-invades the colon and causes bloody diarrhea called amoebic dysentery; also causes amoebic liver abscess Cryptosporidium parvum-more prevalent in immunocompromised Cyclospora cyatenensis-small intestine mucosa, may cause diarrhea for weeks B. coli-large motile ciliated parasite that lives in the colon of pigs, humans, and rodents that can lead to colonic ulceration Enterocytozoon bienusi-microsporidian in small intestine of immunocompromised

tissue invasive toxins in Strep pyogenes

GAS (group A strep)-hemolysins (streptolysin O and S), streptokinase, DNAses, hyaluronidase, NADase tissue destruction, red rash with lots of pus, one toxin causes necrotizing fascitis

Gram Positive Respiratory Tract Infection examples

GAS, GBS, S. pneumoniae (Pneumococcus), Diphtheria (Corynebacterium diphtheria)

Streptococcus pyogenes

GAS-beta hemolytic GPC in chains, can cause strep throat hyaluronic capsule resists phagocytosis M protein facilitates attachment to host cells; antigenic cross-reactivity (auto-Ab) with endocardium and synovial connective tissues streptolysin O and S digest RBCs (hemolysins) erythogenic/pyrogenic exotoxin causes rash of scarlet fever and TSS sx streptokinase activates plasminogen, digests fibrin hyaluronidase breaks down hyaluronic acid in connective tissues pharyngitis 2-4d after exposure to the pathogen sore throat, fever, malaise, and HA, posterior pharynx appears erythematous with an exudate and cervical lymphadenopathy throat culture, RADT (rapid antigen detection test)-15 minutes penicillin V 500mg BID for 10d, benzathine penicillin 1.2mu IM for one dose, clindamycin 300mg q8h for 10d for immediate hypersenativity to penicillin, azithromycin 500mg for five days or clarithromycin 250 mg BID for 10d for resistant strains of GAS that vary geographically with macrolides

Zika and GBS

GBS-uncommon, autoimmune, damages nerve cells causing muscle weakness and even paralysis, severe cases can hinder breathing strong association, but only a small portion of people with recent Zika get GBS

Dysentery

GI tract inflammation often associated with blood and pus in the feces with pain, fever, or abdominal cramps. Usually large intestine disease

Haemophilus influenzae meningitis

GNC/B, facultative anaerobe that usually develops first as ear or sinus infection Prophylaxis for close contacts for 30d-household, daycare, nursing home, etc. differential sx: occasional purpuric/petechial lesions, joint involvement most common cause of meningitis in children until it became a required vaccine

Kahoot-morphology of Pr. Mirabilis

GNR

Yersinia pestis

GNR (coccobacillus), facultative anaerobe, protein capsule, bipolar/safety pin staining, obligate intracellular pathogen, motile, leaves thick anti-phagocytic slime layer in its path bubonic/pneumonic plague transmission: zoonotic host, humans are accidental hosts (camping in the bush) e.g. ingestion of infested animal or flea bite Sylvatic plague- rodents, rabbits, domestic cats Urban plague - Rat reservoir - bite by rat fleas Human to human spread is rare except with pulmonary involvement prevention-flea avoidance DOC-aminoglycosides (streptomycin, gentamicin)

H. influenzae

GNR, #1 cause of meningitis until Hib vaccine sinusitis, otitis media/externa, bronchitis, sepsis, meningitis Serious Hib can be fatal w/o tx epiglottis-severe sore throat w/o remarkable pharyngitis-big cherry at the base of the tongue virulence factors-six types are encapsulated (nonencapsulated cause OM and complicate COPD), type b is pathogenic and invasive occurs mainly in young children and adults weakened by preexisting lung disease transmission-droplet spread and direct contact, casual contact (rare) incubation: 1-3d, communicability: while ill and 24h post abx DOC for URI: TMP-SMZ vaccine contains Hib capsule

Serratia

GNR, facultative anaerobe

*Proteus

GNR, facultative anaerobe, doesn't ferment lactose, motile produces urease which splits urea in CO2 and ammonia, raising pH (normal 5.5)

Enterobacter

GNR, facultative anaerobe, motile

Salmonella

GNR, motile, facultative anaerobe, nonspore-forming leading cause of bacterial food-borne diseases 2000 strains, 5 serotypes infect humans -typhi, paratyphi, typhimurium, cholerasuis, and enteritidis

Pseudomonas aeruginosa

GNR, non-lactose fermenter, motile, straight or slightly curved, comes in pairs, opportunistic pathogen facultative anaerobe-using nitrate or arginine instead of oxygen. found in soil, decaying organic matter, vegetation, intestinal flora, and water thrives on moist hospital surfaces e.g. catheters, dialysis, sinks and mops Resistant to most abx and disinfectants - polysaccharide (alginate) capsule (appear mucoid) Pyoverdin strain (yellow-green) - used in iron metabolism Pyocyanin strain (blue) - catalysis superoxides (toxic forms of oxygen) Pyorubin strain (brown) Endotoxin A (similar to diphtheria toxin), some strains possess antiphagocytic capsule that also aids in adhesion colonizes/infects immunocompromised hospitalized pts (weak invasive ability) two drug bug due to resistance

Klebsiella pneumoniae

GNR, nonmotile, encapsulated, lactose-fermenting, facultative anaerobe, MDR

KEE

GNR-lactose fermenters-Klebsiella pneumoniae, E. coli (#1), Enterobacter

Kahoot-morphology of Enterococcus faecalis

GPC

*Morphologic Characteristics of Bacteria

GPC clusters: Staph (aureus is coagulase positive) GPC pairs: Strep pneumoniae GPC chains: Strep GPR: Listeria, Propionibacteria, Corynebacteria, Gardnerella, Lactobacillus, Clostridium and Bacillus (spore-forming) GNC: Neisseria GNR lactose fermenters: Aeromonas, Vibrio, E. coli, Klebsiella, Enterobacter, Citrobacter GNR non-fermenters: Pseudomonas, Flavobacterium, Proteus, Serratia, Morganella, Salmonella, Shigella GNCB: Acinetobacter, H. influenzae Moraxella

Dr. North GAS summary

GPC in chains, anaerobic, Group A Strep sx: sore throat, white patches observe: pink eye, meningitis, bacteria pneumonia

Dr. North GBS summary

GPC in chains. Group B strep no specific sx, general fever elderly and children affected most

Staphylococcus saprophyticus

GPC in clusters, coagulase negative, facultative anaerobe, common in sexually active young women (if asymptomatic with culture-most likely contaminant)

Enterococcus

GPC, often occurs in pairs (diplococci) or chains, facultative anaerobe

Dr. North Staph aureus summary

GPC; 500,000 infected each year and 50,000 deaths each year symptoms: pneumoniae, endocarditis; MRSA-no vaccine

morphology bacillus anthracis

GPR

*bacillus anthracis

GPR (single, paired, or long chain), aerobic, forms endospores Human - exposure to contaminated meat or animal products -Spores can survive for long time in the environment -Spores germinate, tissues fill with black (anthrac) blood, form coal-black scab Only bacterium with total protein capsule Four modes of infection: inhalation, cutaneous (direct contact/broken skin), ingestion (rare), injection (drug use) Acellular (Anthrax Vaccine Adsorbed-AVA)— BioThrax (USA) - Live spores (Russia) Treatment: ciprofloxacin or doxycyline combined with one or two antibiotics. Amoxicillin is recommended for naturally acquired cutaneous anthrax Mortality rate even after treatment -Inoculation or cutaneous - 28% -Gastrointestinal - ≥ 40% -Inhalation - 45% -Anthrax meningitis is nearly always fatal, even with treatment

Listeria monocytogenes meningitis

GPR common in neonates, elderly, alcoholics, and immunocompromised transmission via GI tract colonization, gut lumen penetration, food e.g. coleslaw, unpasteurized milk/cheese, raw beef and poultry

Dr. North diphtheria summary

GPR, club shaped, nonspore forming D in DPT vaccine, infection of Corynebacterium diphtheriae observe: bull neck, grey patch sx: cyanosis, foul smell ("sweetish"), fever >104, chills, fatigue children are at risk DOC-penicillin, erythromycin

Clostridium botulinum

GPR, olbligate anaerobe, spore-forming, heat resistant (120C) prefers restricted oxygen exposure, pH >4.6 (low acidity), and temp 25-37C postulated mechanism: neurotoxin binds specific Rs at the presynaptic nerve terminal and is internalized into the nerve cell. The toxin then acts against proteins needed for NT release (e.g. dopamine, serotonin, somatostatin, NE, GABA) most potent bacterial poison-1g aerosolized could kill 1.5 million people no smell or taste and no degradation in stomach

Clostridium difficile

GPR; anaerobic spore-former, widely distributed in environment normal flora of colon in 2% of children and 10-20% of adults (disruption=infection) pseudomembranous enterocolitis-epithelial necrosis and formation of pseudomembranes-thin gray-white exudative layer composed of necrotic epithelium bacteria, and neutrophils merged with underlying mucosa toxin A causes diarrhea; B is cytotoxic to GIT cells sx: severe cramping, bloody diarrhea, characteristic foul odor electrolyte disturbance, toxic megacolon, perforation and endotoxic shock almost exclusively complication of abx (clindamycin, lincomycin, ampicillin, cephalosporins) or chemotherapy (methotrexate) infectious strains are resistant to FQ due to overuse in hospitals and community

Clostridium perfringens

GPR; anaerobic, nonmotile; spores (rare), beta hemolysis; cause gas gangrene more widely spread than any other pathogen (cuts, trauma) 5 strains based on toxin produced generation time 6.3min in thioglycollate medium; incubation 1h-several weeks tissue should have oxygen tension <30%

Symptoms of Entamoeba histolytica

Generally mild Diarrhea and abdominal pain Amebic dysentery = severe symptom -Severe stomach pain -Blood and mucus in feces -High temperature fever -Seldom invades liver and cause abscess Ulcer enlargement and disease progression -ameba expand laterally and downward into lamina propria -localized sloughing (ulcers coalesce) -perforation of intestinal wall -peritonitis -secondary bacterial infections -local abscesses -ameboma (=amebic granuloma) ameboma = inflammatory thickening of intestinal wall around the abscess (can be confused with tumor)

Clinical manifestations of genital HPV infection include

Genital warts and cervical cellular abnormalities detected by Pap tests,

protozoa of major concerns

Giardia duodenalis-sever acute diarrhea, chronic diarrhea, nutritional disorders E. histolytica-highly virulent and invasive, lethal systemic disease Apicomplexa and Microsporidia-normally do not evoke severe disease, but may cause life-threatening diarrhea in immunocompromised T. vaginalis-urogenital tract, STD

Kahoot-Used for CBC differential to test for blood borne parasites

Giemsa stain

lymphatic filariasis dx

Giemsa stained thick blood films for the presence of microfilariae W. bancrofti shows marked nocturnal periodicity-collect between 10pm and 1am

culture for TB

Gold Standard Conventional -Solid media --Egg based (Lowenstein-Jensen) --Agar based (Middlebrook 7H10/11) -Liquid media (Middlebrook 7H12) Automated -BACTEC 460 TB (Radiometric)

*H5N1 protective and mitigating responses

Governmental preparedness Cross Sector planning and collaboration Cross Boundary planning and collaboration Expansion of Surveillance, Case tracking and Epidemiology Laboratory Diagnostic Enhancement Improved information systems Coordination of services. Multi-sectoral procedures should be put in place to coordinate the work of agricultural, veterinary and public health services (and any other sectors deemed appropriate in a country context) and facilitate the exchange of laboratory and epidemiological data.

intraabdominal infections

Gram (-) (Escherichia coli, Klebsiella spp., Pseudomonas aeruginosa, Proteus, Enterobacter), anaerobes (Bacteroides, Clostridium, Prevotella, Peptostreptococcus, Fusobacterium, Eubacterium), gram (+) (Streptococcus, Enterococcus, Staphylococcus aureus)

*Staphylococci

Gram-positive cocci in clusters

griseofulvin

Grisactin, Fulvicin, fungistatic-disrupts mitotic spindles (mammals less sensitive) mainly effective for dematophytes and requires several weeks of therapy to incorporate into keratin PO, common in veterinary use, triazoles are more effective in humans SE: nausea, hepato- and renal toxicity, photosensitivity

GBS-Strep

Group B strep-S. agalactiae-beta hemolytic GPC in chains causes pneumoniae, meningitis, and sepsis. Meningitis in babies is non-specific: fever, vomiting, listless, poor feeding, and irritability occurs ar any age, but peaks in babies <1mo. Increasing adult incidence secondary to cancer, renal/liver failure, stroke and nursing home residences. 25% of women carry GBS vaginally, 26500 US cases annually, 7600 newborns transmission: direct contact with an infected person incubation 2-5d; communicable: during illness or 24h post abx tx (DOC-penicillin)

GBS

Guillaine-Barre Syndrome-rare autoimmune disorder involving the peripheral nervous system, most common form of acute inflammatory peripheral neuropathy specific cause unknown but usually develops after viral or bacterial injection sometimes triggered by surgery or vaccinations

influenza A subtypes

H3N2 (Netherlands), H9N2 (Hong Kong) and H1N1 are common among humans; H5N2 avian vaccine; H9N2 and H5N1 avian flu; HA-18 subtypes; NA-11 subtypes; all circulate in birds influenza B are not in subtypes, but can be broken down into lineages and strains. Circulating viruses currently belong to B/Yamagata and B/Victoria lineages

HCV therapy

HCV does not integrate into host genome so a cure is realistic in most cases SVR-sustained virologic response-defined as an absence of HCV RNA for 12w AFTER the completion of therapy

enveloped DNA viruses

HERPES-icosahedral HEPADNA-icosahedral POX-complex all are double-stranded

*DNA viruses

HHAPPPy-Herpes, Hepadna, Adeno, Papova, Parvo, Pox *most are doublestranded with icosahedral symmetry that replicate in the nucleus* parvo-single strand of DNA pox-complex dsDNA that encodes for hundreds of proteins which form a complex structure around the DNA that looks like a box (POX in a BOX)

HIV vs hepatitis in dried blood

HIV-no envelope-will die in 7h; hepatitis-will die in 7d

immune evasion among pathogens

HIV: depletion of CD4+ lymphocytes HCV: production of proteins that interfere with B- and T-cell responses to infection

Kahoot-Which is caused by DNA virus?

HPV

Anogenital Squamous Cell Cancers

HPV is causally associated with cervical cancer (99%) and other anogenital squamous cell cancers (anal, penile, vulvar, vaginal) persistent infection with oncogenic type is necessary but not sufficient for cancer

eosinophils

Has a bi-lobed nucleus and heavily granulated cytoplasm Involved in parasite defense and allergic response

food poisoning from enterotoxins

Heat stable toxin from S. aureus and Bacillus cereus

Gram Negative Respiratory Tract Infection examples

Hib, B. pertussis, Pseudomonas, Acinetobacter baumannii

Dr. North Haemophilus influenzae summary

Hib-type B-one of six types, encapsulated, gram - 1/100,000 children affected since 1990 vaccine diagnosis: culture, CXR, or latex particle agglutination DOC-TMP-SMZ

clinical presentation acute prostatitis

High fever, chills, malaise, myalgia, localized pain, frequency, urgency, dysuria, nocturia, retention Prostate is swollen, tender, tense, enlarged gland Bacteriuria, bacteria in prostatic secretions

Genital Warts and High-Risk HPV

High-risk HPV types occasionally can be found in visible warts and have been associated with squamous intrepithelial lesions (squamous cell carcinoma in situ, Bowenoid papulosis, Erythroplasia of Queyrat, or Bowen' s disease of the genitalia). The lesions can resemble genital warts. Unusual appearing genital warts should be biopsied.

CSF lacks defense mechanism

Host defense mechanisms in subarachnoid space are unable to combat bacteria so bacteria replicate freely in CSF and can lead to meningitis

other hosts WNV

Hosts - reptiles and amphibians Reservoirs - birds and small mammals Predominant bird host - American crow -Dead crow (sentinel or early warning)

caspofungin

IV, active against Candida and Aspergillus

india ink

Identify capsules-Cryptococcusneoformans-only encapsulated pathogenic yeast

distinguishing between ulcer and H. pylori

If it stops hurting for a while after you eat it's H. pylori

Kahoot-Ab that can be passed to baby through breast milk

IgA