Microbiology Lecture Exam 4: chapters 19,20,21,22,23
Staphylococcus: Pathogenicity
- 3 structural defenses against phagocytosis - Cell free coagulase - Bound coagulase - Hyaluronidase - Staphylokinase
Chlamydia trachomatis pathogenesis
- Limited host range - humans; 1 strain infects mice - enters body thru open wounds/cuts; - infects the conjunctiva and various mucous membranes (Ex: trachea, bronchi, urethra, uterus, uterine tubes, anus, and rectum) - symptoms happen due to cell destruction & inflammation - major cause of eye infections worldwide
Listeria monocytogenes Diseases
- Meningitis and sepsis in newborns and immunocompromised adults. - Gastroenteritis - pregnant women can transmit Listeria to fetus: cause - - premature delivery, miscarriage, stillbirth, meningitis in newborn
Signs and symptoms of trachoma usually affect both eyes and may include:
- Mild itching and irritation of the eyes and eyelids - Discharge from the eyes containing mucus or pus - Eyelid swelling - Light sensitivity (photophobia) - Eye pain
N. meningitidis sympthoms
- Most cases are meningitis - Symptoms include abrupt sore throat, fever, headache, stiff neck, vomiting, and convulsions
Neisseria meningitidis epidemiology
- Most common cause of meningitis in people under 20 years of age - Can be normal microbiota of the upper respiratory tract - Bacteria transmitted by respiratory droplets among people living in close contact - Meningococcal septicemia can also be life threatening
Chlamydia trachomatis Epidemiology
- Most common reportable bacterial sexually transmitted disease in U.S. - Women under age 20 are most susceptible to infection. - - The organism is also responsible for more than 500 million ocular infections worldwide - Doctors estimate 3.5 million asymptomatic cases go unreported
T. pallidum pallidum: prevention
- No vaccine available - abstinence, monogamy, and safe sex
Rickettsia Physiology, epidemiology
- Non-motile, aerobic bacteria - Outer membrane of LPS with endotoxin activity - Transmitted via arthropod vectors - Bacteria live in the cytosol of host cell
Mycobacterium tuberculosis
- Not highly virulent - 90-95% of infections cleared by immune system; subclinical - respiratory disease - multi drug resistant strains
Chlamydia trachomatis ect
- 85% in women are asymptomatic; <75% of infections in men has symptoms - Infected men can also have: Urethral inflammation (which cannot be distinguished from gonorrhea based on symptoms alone) - Infected individuals may also experience proctitis (inflammation of rectum) - Women can develop pelvic inflammatory disease (PID) - Chromic pelvic pain, infertility, irreversible damage
C. trachomatis diseases Trachoma prevention
- Abstinence to prevent sexually transmitted infections - Blindness prevented with prompt use of antibacterial agents - Developing vaccine shows promise in mice
B. pertussis pathogenesis
- Adhesions and toxins mediate the disease - Bacteria inhaled in aerosols multiply in epithelial cells
Neisseria
- Aerobic, nonmotile, and arranged as diplococci - Oxidase positive - Two species pathogenic to humans: - N. gonorrhoeae - N. meningitidis
1. The "gold standard" of antifungal drugs is amphotericin B. What is its target?
- Amphotericin B is gold standard of antifungals - One of the more toxic antifungal agents - Used for treating systemic mycoses and other fungal infections that do not respond to other drugs
N. gonorrhoeae diagnosis
- Asymptomatic cases identified with genetic probes - Gram-negative diplococci in pus from inflamed penis -Cervical swab in females
M. tuberculosis prevention
- Attenuated M. bovis strain is used in BCG immunization in other countries - Avoid inhaling respiratory droplets from TB patients
Candida albicans - Candidiasis diagnosis
- Based on signs & demonstration of clusters of budding yeasts
C. trachomatis diseases Trachoma
- Ocular disease - Leading cause of nontraumatic blindness in humans - Spread through contact with the eyes, eyelids, and nose or throat secretions of infected people - Causes corneal abrasions that lead to blindness - Infection typically occurs during childbirth
Gonorrhea in women
- Often asymptomatic Can trigger pelvic inflammatory disease
Neisseria gonorrhoeae epidemiology
- Only occurs in humans - STD - Most cases in the US (ages 15-24) - More common in females than in males Symptoms usually lacking in women
B. pertussis diagnosis
- Pertussis symptoms usually diagnostic
N. meningitidis prevention
- Prevention - Asymptomatic carriers make eradication unlikely - Vaccine against some meningococcal strains is available
Apicomplexans: Plasmodium Prevention
- Prevention - Mosquito control - Travels to endemic areas can take atovaquone & proguanil several days before and for one week after travel
B. pertussis treatment
- Primarily supportive - Antibiotics have little effect on the course of the disease - Erythromycin recommended for everyone in contact with a whooping cough patient
Clostridium botulinum prevention
- Proper canning of food - infants under 1 year should not consume honey
Apicomplexans: Plasmodium - Signs and Symptoms continued
- Proteins can cause erythrocytes to adhere to capillary lining & block blood flow - Leas to small hemorrhages
Neisseria meningitidis diagnosis
- Rapid diagnosis critical - Spinal tap for CSF - Gram-negative diplococci in phagocytes of the CNS
B. pertussis symptoms
- Runny nose, sneezing, mild cough, low-grade fever
Staphylococcal diseases: Cutaneous: Scalded Skin Syndrome
- S. aureus causes pyogenic lesions; reddening of skin, begins near mouth, spreads over entire body, followed by large blisters w/ clear fluid lacking bacteria or WBCslacks bc syndrome caused by exfoliative toxin
Compare and contrast biological and mechanical vectors Be able to identify examples of each.
- Biological vectors, such as mosquitoes and ticks may carry pathogens that can multiply within their bodies and be delivered to new hosts, usually by biting. - Mechanical vectors, such as flies can pick up infectious agents on the outside of their bodies and transmit them through physical contact.
True fungal pathogens
- Blastomyces dermatitidis - Coccidiodes immitis - Histoplamsa capsulatum - Paracoccidioides brasilensis
dermatophytoses (tinea)
- Chronic superficial fungal infection of the skin (skin, nails, or hair) - Previously called ringworms - Fungi use keratin as nutrient source and colonize dead tissuesTinea Pedis (Athlete's Foot) - between toes and on soles of feet. Tinea Cruris (Jock Itch) - groin area.
M. tuberculosis treatment
- Common antimicrobials ineffective - Combination therapy used for months to treat the disease
N. gonorrhoeae treatment
- Complicated due to resistant strains - Broad-spectrum intramuscular cephalosporins
Staphylococcal diseases: Systemic: Endocarditis
- Damage to lining of heart - have non flu-like symptoms but quickly deteriorates as blood pumped from heart drops (50% patients don't live)pale skin, fever, chills, swollen legs/feet
Candida albicans - Candidiasis treatment
- Depends on affected area - Nystatin for oral candidiasis in infants & kids - Azole creams and/or oral fluconazole for vaginal cadidiasis
T. pallidum pallidum: diagnosis
- Diagnosis: antibody tests against bacteria antigens - Tertiary difficult to diagnose (bc symptoms can be similar to other diseases)
Corynebacterium diphtheriae pathogenesis
- Diphtheria toxin = A-B exotoxin acquired via lysogeny inhibits polypeptide synthesis
C. trachomatis diseases Trachoma treatment
- Doxycycline or erythromycin for 21 days (genital & ocular infections) - Newborns treated with azithromycin cream for 10-14 days - surgical correction of deformities can prevent blindness
T. pallidum pallidum: Tertiary syphilis
- Due to complications from inflammation and hyperimmune response against pathogen - Damage to brain, nerves, eyes, heart, liver, bones, & joints - Causes syphilitic lesions called gummas - MOST serious stage
Bacillus (gram + rod shaped)
- Facultative anaerobes bacilli occur singly, in pairs, or chains - forms endospores, normally in soil - structures resistant to harsh environment conditions allowing to survive for a long tim
Three categories of clinical manifestation:
- Fungal infections: Most common mycoses & Caused by presence of true pathogens or opportunists - Fungal toxicoses: Acquired through ingestion & Occur when poisonous mushrooms are eaten - Allergies: Most often result from the inhalation of fungal spores
M. tuberculosis epidemiology
- Global pandemic - 1/3 of world's population infected - Leading causing of death in HIV infected individuals - occurring mostly among foreign-born individuals - MDR and XDR strains
Neisseria gonorrhoeae pathogensis
- Gonococci adhere to the genital, urinary, and digestive tract -Gonococci can evade the immune system - Secrete protease that cleaves secretory immunoglobulin A (IgA) - Survive within neutrophils
Streptococcus Diagnosis
- Gram stain of sputum smears - culture of sputum sample can be difficult bc pneumococci have fastidious requirement & cultures often overgrown by normal oral microbiota chest x-ray
B. pertussis prevention
- Immunization with diphtheria, tetanus, attenuated pertussis (DTaP) or Tdap vaccine
Symptoms associated with N. gonorrhoeae
- Infections can occur outside the reproductive tract - Cause proctitis, pharyngitis, and gingivitis - Infection of the cornea or respiratory tract of newborns can occur during childbirth
Gonorrhea in men
- Inflammation causes painful urination and pus-filled discharge
Staphylococcal diseases: Noninvasive pathogencity
- S. aureus common of food poisoning, disease caused by enterotoxins left in food from growth of bacteria - food must remain room temp or warmer for several hours for bacteria to grow, reproduce, secrete toxins warming or reheating food doesn't inactivate entertotoxins but heating kills bacteria
Staphylococcal diseases: Cutaneous: Impetigo
- S. aureus; small, flattened, red sores, quickly rupture & oozes for few days, then forms yellowish brown crust (face & limbs); develop pus-filled vesicles that crust
Streptococcus treatments
- S. pneumoniae sensitive to most antimicrobial drugs, sample needed before drug therapy begins - Penicillin choice of drug, cephalosporin, erythromycin, chloramphenicol also effective resistant strains have emerged
Chlamydia trachomatis: Lymphogranuloma venereum
- STD;1.Initial genital lesion at site of infection - typically overlooked as these are painless and heal quickly - 2nd stage involves buboes(swollen lymph nodes) & results fever, chills, anorexia, muscle pain; can enlarge to where they'll rupture,
Staphylococcus treatments
- Semi synthetic form of penicillin - methicillinMRSA (resistant) emerged causing problem in health care setting, more ppl die from MRSA than - HIVVancomycin used to treat MRSA infections - Staphylococcus can't be eliminated
N. gonorrhoeae prevention
- Sexual abstinence, monogamy, and proper condom use - Eye infections in newborns prevented with antimicrobials
Plasmodium: genetic traits
- Sickle cell trait - Hemoglobin C - Deficiency of glucose - phosphate dehydrogenase - Lack of Duffy antigen on erythrocytes
T. pallidum pallidum: Secondary syphilis
- Sore throat, headache, mild fever, malaise, myalgia, & widespread rash - lesions filled with spirochetes - can infect others (rare)
Candida albicans - Candidiasis
- The most common is Candida albicans, which causes vaginal yeast infections in women
Prevotella
- They can also cause gynecological infection, brain abscesses, and abdominal infection
Corynebacterium diphtheriae diesease
- Toxemia can result targeting organs - fluid thickens into pseudomembrane that can cause suffocation by completely blocking respiratory passages (cause asphyxia)
M. tuberculosis diagnosis
- Tuberculin skin test - Chest X-rays identify individuals with active disease - AFS of sputum
Treponema pallidum pallidum: Disease
- Untreated syphilis has four phases:Primary, secondary, latent, and tertiary - Congenital syphilis •An infected mother can transmit Treponema to her fetus - Can result in fetal death or mental retardation and malformation
Candida albicans - Candidiasis signs & symptoms
- Vaginal candidiasis manifests as white mucoid colonies on vagina - Severe vaginal itching, painful intercourse, vaginal discharge like cottage cheese - White patches in mouth
T. pallidum pallidum: Latent syphilis
- after several weeks or months rash disappears & patient enters latent stage clinically inactive _ may last up to 30 years
Clostridium botulinum
- anaerobic, endospore forming bacillus common in soil & water; - endospore survive improper canning of food germinating to produce vegetative cells that grow & release powerful neurotoxins that causes botulism - neurotoxins prevent muscular contraction, resulting flaccid paralysis
Clostridium botulinum (botulism)
- blurred/double vision, weakness, difficultly swallowing, dropping of upper eyelids, dilated pupils, constipation
Staphylococcus structural defenses: Hyaluronidasey
- breaks down hyaluronic acid (component of matrix between cells) - found on 90% of S. aureus strains - allows bacteria spread between cells all over body
Apicomplexans: Plasmodium
- causative agent of malaria 4 species cause most infection: P. falciparum, P. vivax, P. ovale, P. malariae, - P. knowlesi emerging human pathogen - anapheles mosquitoes are vectors - life cycle has 3 prominent stages: liver, erythrocytic, sporogonic stage
Clostridium tetani treatment
- cleansing of wounds removing endospores - TIG - antimicrobial drugs - active immunization w/ tetanus toxoid
Candida albicans
- common causative agent - Common microbiota of the skin and mucous membranes - Fungus forms long cellular extensions called pseudohyphae
Staphylococcus diagnosis
- detect Gram + bacteria in grapelike arrangements - S. epidermidis usually coagulase -
Rickettsia
- extremely small appears almost wall-less due to small amount of peptidoglycan - obligate intracellular parasites(cant reproduce w/o host): unusual since they have functional genes for protein synthesis, ATP production, & reproduction (characteristics of cells) - 4 genera : Rickettsia, Orientia, Ehrlichia, and Anaplasma
Clostridium tetani epidemiology
- found in soil, dust, GI tract of animals & humans - trivial injuries (break in skin or mucous membrane allow endospores in) - iv drug user @ risk - can cause death in most cases in less developed countries
L. monocytogenes: pathogenesis
- is an intracellular (inside) pathogen; grows in phagocytes in gallbladder - Listeriolysin O helps Listeria avoid digestion by host cell (phagosome) - actin tail allows for cell to cell spread - grows & reproduce in cytosol, away from antibody immune system
Listeria monocytogenes epidemiology
- large, non-endospore forming bacillus, gram + - found in soil, water, & animals - enters body thru contaminated food & drinks (causes listeriosis) symptoms: mild flulike symptoms in healthy nonpregnant adults
Spirochetes: Borrelia (gram-)
- lightly staining, spirochetes - causes 2 diseases in humans: Lyme disease & relapsing fever
Apicomplexans
A type of parasitic protozoan. Some apicomplexan cause serious human disease
Trypanosoma brucei
African sleeping sickness
Closridium tetani prevention
DTaP and Tdap
Staphylococcus: structure&physiology
2 species common 1. Staphylococcus aureus= most virulent strain - variety of conditions depending on site of infection 2. Staphylococcus epidermidis = normal microbiota of human skin - opportunistic infections
Staphylococcal diseases: Systemic: Pneumonia
Pneumonia 1. inflammation of lungs which alveoli & bronchioles are filled w/ fluids empyema occurs when pus fill lungs10% patients, infection spreads to space between lungs & chest wall where pus builds up (empyema)coughing produce phlegm, fever, sweating, chills, SOB, chest pains
Haemophilus influenza
Pneumonia, bacteremia, meningitis
Naegleria fowleri
Primary amebic meningoencephalitis (PAM; destruction of brain tissue)
Taenia saginata
beef tapeworm
Diphyllobothrium latum
broad or fish tapeworm
Yersinia pestis
bubonic plague
Streptococcus pyogenes (GAS) Structural features to evade phagocytosis 6
c5a peptidase- destorys c5a
Clostridium difficile
colitis
Clostridium difficile epidemiology
common in the intestinal microbiota: opportunistic
Fasciola hepatica
common liver fluke
Streptococcus: Group A diseases: Rheumatic fever
complicated untreated pharyngitis; inflammation leads to damage of heart valves & muscle autoimmune response against heart antigens subcutaneous nodules at joints common in 5-15 yr old children, damage to heart valve can be so bad it must be replaced w/ patient reaches middle age
C. trachomatis diseases Trachoma diagnosis
demonstrate bacteria inside cell from site of infection
Staphylococcus aureus diagnosis
detecting staphylococci in pus, blood or (coagulase test)
Clostridium difficile diagnosis
diarrhea in patients taking antimicrobial drugs suggest infection isolation of organism from feces demonstrate presence of toxins by immunoassay
Schistosoma
dioecious blood fluke; causative agent of schistomiasis (common name snail fever)
Corynebacterium diphtheriae
diphtheria
Streptococcus mutans signs and symptoms
discoloration or hole in tooth; pain, throbbing, sensitivity
Mycoses
diseases caused by fungi superficial, deep, or opportunistic
staphylococcus aureus prevention
hand antisepsis (washing hands)
Streptococcus mutans epidemiology
high sucrose diets
T pallidum pallidum: Primary syphilis
small, painless, reddened lesions called chancre forms 10-21 days - lesions typically form on cervix - 1/3 of cases: disappearance of chancre is end of infection - However in most cases, bacteria > blood, leading to secondary
Clostridium difficile treatments
stop antimicrobial drug to resolve minor infections serious cases treated w/ vancomycin or metronidazole bleach effective to kill endospores
Streptococcus pyogenes
strep throat, scarlet fever
Clostridium botulinum treatments
if food borne antibiotics are not effective -wash intestinal tract to remove bacteria -give neutralizing antibodies against botulism toxin -give antimicrobial drugs in infant & wound botulism cases
Staphylococcus structural defenses: Cell free coagulase(same as bound coagulase)
trigger blood clotting combines w/ blood protein before becoming enzymatic & converting fibrinogen to fibrin threads Fibrin clots around bacteria in effect hides bacteria from phagocytic cells
Clostridium tetani diseases
trisumus (lockjaw), risus sardonicus, opithotonus
Salmonella typhi
typhoid fever
Streptococcus: Group A diseases: Pharyngitis
"strep throat', inflammation of the pharynx with pus patches, fever. Can lead to laryngitis (throat/voice box) or bronchitis (lungs)
Describe the life cycle of Plasmodium and relate malarial symptoms to stages in the life cycle.
- liver stage, erythrocytic cycle (in human), sporogonic phase (in mosquito) - two weeks after the erythrocytic cycle begins, symptoms of fever, chills, diarrhea, headache, and pulmonary/cardiac dysfunction happens - fever correlates to erythocyte lysis - loss of erythrocytes leads to anemia, weakness, and fatigue - the inability of the liver to process hemoglobin leads to jaundice
Corynebacterium diphtheriae epidomology
- non-endospore - colonizes skin & respiratory, GI, urinary, & genital tracts -transmitted from person to person via respiratory droplet or skin contact
Tuberculosis signs and symptoms
- often limited to minor cough or fever - more severe: breathing difficulty, fatigue, chest pain, coughing up blood, weight loss
Clostridium tetani pathogenesis
- once inside, produce tetanospasmin toxin: potent neurotoxin released by C. tetani when cells die causes continuous muscle contractions tightening of jaw&neck muscles spasms & contraction can spread to other muscles continuous contraction of diaphragm
Streptococcus Alpha-hemolytic: Viridans group: S. mutans
- opportunistic pathogens lives in mouth, pharynx, GI tract, genital tract, urinary tract - cause of dental caries & dental plaques(Tooth decay) - once in the blood, can cause meningitis & endocarditis
Plasmodium virulence factors
- parasite hidden from immune surveillance when in RBCs - malaria secretome releases toxins & enzymes into host - adhesins help parasite avoid clearance in spleen - merozoites avoid immune cells of liver - some species form formant hypnozoites(latent) - induce "bite me" chemicals signal in humans
Bordertella pertussis
- pertussis (whooping cough) - Most cases of disease are in children
Staphylococcal diseases: Systemic: Bacteremia
- presence of bacteria in blood - health care associated infections accounts about half of cases
Corynebacterium diphtheriae diagnosis
- presence of pseudomembrane - Elk test to confirm(use of antibodies against toxins w/ toxin in sample of fluid from patient)
Staphylococcus structural defenses: Staphylokinase
- produced by S. aureus, dissolves fibrin threats in blood clots - freeing bacteria from clot - when space & nutrients becomes limit, digests out of clot w/ this enzyme & spread to new locations
Listeria monocytogenes prevention and treatment
- proper food handling, cooking, and reheating - Ampicillin for severe cases
T. pallidum pallidum: Congenital syphilis
- results when bacteria crosses placenta from infected mother to fetus - if mother experiencing primary or secondary syphilis often can result fetal death or mental retardation & malformation
Vibrios (gram-)
- slightly curved bacilli w/ single polar flagellum - Found in water environments worldwide - Common species to infect humans - Bacteria can survive in freshwater
Clostridium tetani
- small, motile, obligate anaerobe bacilli w/ terminal endospore (lollipop appearance) - live only in anaerobic but endospores survive for years - tetanus results when endospore germinate & produce tetanus toxin
Chylamydias
- smallest bacteria & nonmotile & grows & multiply only in host cells - doesn't have cell wall= has 2 membranes w/o peptidoglycan between membranes - Infections are most common bacterial STDs in humans
Helicobacter pylori
- stomach ulcers - gastritis & most peptic ulcers
Clostridium botulinum diagnosis
- symptoms are diagnostics - culturing sample from contaminated food, feces, patients wound
Apicomplexans: Plasmodium: Signs & Symptoms
- the immune response against the parasites: •Fever •Chills •Diarrhea •Headache •Jaundice •Anemia
Spirochetes(gram -)
- thin, tightly coiled shaped; moves in corkscrew fashion rotation of axial filaments enables bacteria to burrow thru hosts' tissues - 3 genera: Treponema Borrelia, Leptospira
Clostridium botulinum pathogenesis
-C. botulinum strains produce 7 neurotoxins -binds neurons and prevent muscle contraction: Flaccid paralysis
Rickettsia prowazekii
-Epidemic typhus -Louse
Pathogenic fungi
-Infection occurs through accidental contact -Primary pathogens sicken healthy persons -Opportunistic pathogens attack people who are already weakened in some way - often resistant to antifungal agents
Trichophyton
Fungus that causes athlete's foot, ringworm, and jock itch
Clostridium (gram + bacillus)
Anaerobic, endospore forming in soil, water, sewage, GI tract of animals & humans endospores allow for survival in harsh conditions
Streptococcus: Group A diseases: Streptococcal TSS
Bacteremia that causes severe multisystem infections leading to TSSinflammation at sites of infection can cause pain, fever, stock, death by increased pain, organ failure, shock (40% die)
Blastomyces dermatitidis
Blastomycosis; rare but often fatal fungal disease - Pulmonary blastomycosis (inside lungs) - Cutaenous blastomycosis (spread outside to lungs)
Compare and contrast true fungal pathogens with opportunistic fungi
Both- cause fungal infections. - True fungal pathogens- can cause diseases in otherwise healthy individuals, whereas opportunistic fungi can only infect weakened individuals because they lack genes for proteins that help to colonize body tissue. - True fungal pathogens are endemic to certain regions, mostly in Americans, whereas opportunistic fungi are spread throughout the world.
Streptococcus (Gram +)
COCCI IN CHAINS S pneumonia: Alpha hemolysis S pyogenes: Beta hemolysis S mutans: Cavities Catalase - & Facultative anaerobes categorized on Lancefield (groups A&B significant in humans)
Enterobacteriaceae (cre)
Carbapenem-resistant Enterobacteriaceae like KPC (K. pneumoniae carbapenemase)
Trypanosoma cruzi
Chagas disease
Chlamydia trachomatis
Chlamydia, lymphogranuloma venereum, and conjunctiviti
infant botulism
Clostridium botulinum diseases: result from ingestion or inhalation of endospores & colonize GI tract - crying, constipation, failure to thrive - death & paralysis are rare often associated w/ eating honey, parents advised not to feed honey to infants under 1
Wound botulism
Clostridium botulinum diseases: result of contamination of wound by endospores symptoms same as foodborne
Foodborne botulism
Clostridium botulinum diseases: (poisoning) 1-2 days after consumption of toxin in home-canned foods or preserved fish -weak, dizzy, dry mouth, blurred vision, abdominal pain, constipation, progressed paralysis -death bc inability to contract muscles to inhale - slow recovery because damage to nerve cell endings
Clostridium tetani diagosis
Clostridium tetani: diagnosis & treatments physical exam, immune history, characteristic muscular contraction
Coccidioides immitis
Coccidioidomycosis (Valley Fever)
Campylobacter jejuni
Gastroenteritis, Gastrointestinal disease; may cause Guillain-Barre Syndrome
Ehrlichia chafeensis
Ehrlichiosis
Staphylococcus (gram +)
Facultative anaerobes Cells occur in grapelike clusters Nonmotile Salt-tolerant Tolerate salt on human skin Tolerant of desiccation, radiation, and heat Survive on environmental surfaces
What are the three main groups of parasitic helminths?
Flatworms, Thorny-headed worms, and roundworms
Giardia lamblia
Giardiasis
Histoplasma capsulatum
Histoplasmosis
Ancylostoma duodenale
Hookworm
Streptococcus pyogenes (GAS) Structural features to evade phagocytosis 2
Hyaluronic acid capsule = "invisibility clock" acid normally found in body, WBCs may ignore bacteria (camouflaged)
T. pallidum pallidum: treatment
Penicillin drug choice but ineffective against tertiary syphilis
Leishmania spp.
Leishmaniasis
Borellia burgdorferi
Lyme disease
Streptococcus pyogenes (GAS) Structural features to evade phagocytosis(1)
M protein destabilizes(destroy) complement = interfering w/ opsonization & lysis
Staphylococcus aureus treatment
MRSA: vancomycin antimicrobial therapy decolonization
Neisseria meningitidis
Meningococcal disease (meningitis)
Trichomonas vaginalis
Metronidazole (patient and partner)
Ascaris lumbricoides
Roundworm that causes small intestine infection
N. meningitidis pathogenesis
Neisseria meningitidis causes life-threatening disease when it invades the blood or cerebrospinal fluid.
Streptococcus agalactiae (group B streptococcus)
Neonatal infection, chorioamnionitis, and UTI
Contrast definitive host with intermediate host.
Parasitic infections often involve several hosts—a definitive host in which mature (often sexual) forms of the parasite are present and usually reproducing and, with many parasites, one or more intermediate hosts in which immature parasites undergo various stages of maturation.
Clostridium difficile prevention
Proper hygiene to limit nosocomial infections
Streptococcus pyogenes (GAS) Structural features to evade phagocytosis 4
Pyrogenic toxins = stimulate macrophages & immune cells to release cytokines (fever, rash, shock)
Rickettsia rickettsii
Rocky Mountain Spotted Fever (hard ticks)
Schistosoma spp.
Schistosomiasis (snail fever)
Shigella sonnei
Shigellosis
Prevotella species
Sinus and ear infections, Brain abscesses, Periodontal disease
S. aureus
Skin and soft tissue infections like abscesses, furuncles, and cellulitis, toxic shock syndrome
Streptococcus pyogenes (GAS) Structural features to evade phagocytosis 3
Streptokinase = break down blood clots
Streptococcus pyogenes (GAS) Structural features to evade phagocytosis 5
Streptolysins = kills RBCs, WBCs, platelets
Staphylococcal diseases: Noninvasive symptoms
Symptoms = nausea, vomiting, diarrhea, headache, sweating, abdominal pains usually w/in 1-6 hrs
Entamoeba histolytica
amebiasis
Neisseria gonorrhoeae
gonorrhea
Staphylococcal diseases: Systemic: Toxic shock syndrome(non streptococcal)
TSS toxins grow in wound or abraded vaginatoxin absorbed into blood & cause TSSfever, vomiting, red rash, extreme low blood pressure, loss sheets of skinFatal to 5% of patients when BP so low that brain, heart, & other organs have inadequate supply of O2 (shock)occurs in males & females but mostly among women (tampons)
Borrelia burgdorferi
The causative agent of Lyme disease
What are the major characteristics of protozoa?
They are eukaryotic, single-celled, and lack cell walls
Toxoplasma gondii
Toxoplasmosis
Streptococcus pyogenes epidemiology (group a)
Typically infects the pharynx or skin Often causes disease when normal microbiota are depleted Spreads via respiratory droplets
E. coli
Urinary tract infection (UTI), traveler's diarrhea
Pseudomonas aeruginosa
Urinary tract infection, respiratory system infections, dermatitis
Define parasite
an organism that lives in or on another organism (its host) and benefits by deriving nutrients at the host's expense
Apicomplexans: Plasmodium Treatment
antimalarial drugs, chloroquine, pyrimethamine, & artesunate
Streptococcus mutans causative agent
acidogenic oral bacteria
Prevotella intermedia
acute necrotizing ulcerative gingivitis periodontal infections
Streptococcus: Group A diseases: Scarlet fever
can occur following streptococcal pharyngitis infections after 2 days of pharyngitis pyrogenic toxins released by streptococci trigger diffuse rash that begins on chest & spreads tongue becomes strawberry red
arthropod vectors
carry pathogens from one host to another by both mechanical and biological transmission
Vibrio cholerae
causes cholera
Ehrlichia chaffeensis
causes ehrlichiosis; emerging diseases
P. falciparum
causes fever, erythrocyte lysis, renal failure, and dark urine
Mycobacterium leprae
causes leprosy affects cooler body regions
Shigella dysenteriae
dysentery
Streptococcus pyogenes structure and physiology (group a)
facultative anaerobes cocci pairs/chains lancefiled a
necrotizing fasciitis
flesh eating bacterial disease streptococci enter body & spread along fascia Secrete enzymes & toxins that destroy tissues: exotonix a: triggers overactive response that cause more damage (damage healthy) exotonix b: protease that destroys tissue
sty
folliculitis of an eyelash
Clostridium perfringens
gas gangrene, food poisoning
Corynebacterium diphtheriae treatment and prevention
give antitoxin and antitoxins - DTaP vaccine (most preventative way); Tdap booster
Streptococcus: Group A diseases: eysipelas
infection and inflammation of lymph nodes surrounding a streptcoccal infections of "superficial skin layer"
Staphylococcal diseases: Cutaneous: Folliculitis
infection of hair follicle when base of follicle is red, swollen
N. meningitidis treatment
intravenous ceftriaxone
what factors that predispose people to opportunistic fungi?
invasive medical procedures, medical therapies, certain disease, conditions specific, life-style factor
Chlaymdia trachomatis
most commonly affects the urogenital tract. In men, the infection usually is symptomatic, with dysuria and a discharge from the penis; most woman have no symptoms
1. Why is the actual prevalence of fungal infections largely unknown?
most mycoses are not contagious or spread person to person which makes them hard to report
Rickettsia typhi
murine typhus (also called endemic typhus
Streptococcus agalactiae (GBS)
often infects newborns associated w/ neonatal bacteremia, meningitis, & pneumonia
Group A Streptococcus diagnosis
skin infections diagnosed by presence of Gram + streptococci rapid strep test used for respiratory infections (streptococci in pharynx not diagnostic)
Bacillus anthracis
only causes 1 disease - anthrax & has 3 clinical manifestation
Staphylococcal diseases: Noninvasive treatment and prevention
oral rehydration solution (ors) & proper handling, refrigeration and heating will help decrease risk
Group A Streptococcus treatments
penicillin effective Erythromycin or cephalosporin used to treat penicillin sensitive patients person can have strep throat more than once
Streptococcus pneumoniae
pneumonia
T. solium
pork tapeworm
Listeria monocytogenes: diagnosis
presence of bacteria in cerebrospinal fluid of ppl w/ meningitis (rarely seen in gram stain)
Streptococcus mutans pathogenesis
proteinaceous martial in saliva forms pellicle that bacteria colonize metabolism o sucrose leads to biofilm formation and acids
Streptococcus: Group A diseases: pyoderma (impetigo along with s. aureus)
pus forming lesion on exposed skin
Streptococcus mutans treatment and prevention
removing of decayed area, brushing, flossing, reduce sucrose in diet
Primary Tuberculosis
results from initial infection w/ M. tuberculosis (typically infects respiratory tract thru inhalation of droplets from infected person)
Secondary tuberculosis/reactivated TB
results when bacteria breaks stalemate, ruptures tubercle, & reestablishment of active infection after period of dormancy (weakened immune system, poor nutrient, alcoholism)
Disseminated (extrapulmonary) tuberculosis
results when infection spreads throughout body (symptoms arise due to complication at various sites involved)
Enterobius vermicularis
round worm or pin worm; common parasitic worm in U.S.
Treponema pallidum
syphilis
Escherichia coli O157:H7
toxin producing strain of E. coli, leading cause of diarrhea worldwide
Clostridium difficile pathogenesis
toxins cause diarrhea which leads to pseudomembranous colitis
Escherichia coli - ETEC, EAEC
travelers' diarrhea
what is the most significant transmission mode of mycoses
via inhalation, trauma, or ingestion
Staphylococcal diseases: Systemic: Toxic shock syndrome symptoms
vomiting, red rash, extreme low blood pressure, loss sheets of skinFatal to 5% of patients when blood pressure so low that brain, heart, & other organs have inadequate supply of O2 (shock)occurs in males & females but mostly among women (tampons)
Mycoplasma pneumoniae
walking pneumonia
Bordetella pertussis
whooping cough
Candida
yeast infection
Apicomplexans: Plasmodium Diagnosis
•Commonly based on ID using blood smears
Mycobacterium
•Non-endospore-forming •Cell wall is (waxy lipid) mycolic acid •Slow growth •Along with cord factor prevents destruction by lysosomes or macrophages - intracellular growth - Resistance to Gram staining, detergents, many antimicrobial drugs, and desiccation
Treponema pallidum pallidum Pathogenicity and Epidemiology
•Pathogen of humans only •Cannot be cultured outside of cells •Most widespread Treponema strain •Causative agent of syphilis •Occurrence decreases after antibiotic development
Protozoan Parasites of Humans
•Protozoa are unicellular eukaryotes •Protozoa that enter the body via ingestion have two morphological forms: •Trophozoite •Lives within host •Cyst •Dormant; can survive in environment •Trophozoites undergo encystment before leaving the host in feces •Parasites classically grouped by their mode of locomotion •Ciliates, amoebae, flagellates, and apicomplexans
Protozoan Parasites of Humans: Amoebae
•Protozoa with no truly defined shape •Move and acquire food through the use of pseudopods •Found in water sources throughout the world Few cause disease