PHAR6724 Infectious Disease Exam #3

Salmonella typhi

1 serotype. Typhoid fever with symptoms including rash, diarrhea, headache, exhaustion, and bacteremia. Invades by crossing Peyer's patches and is spread systemically by phagocytes

Streptococcus pyrogenes: group type

A

Anaplasma (Ehrlichia) phagocytophilum

Anaplasmosis (human granulocytic ehrlichiosis) - common signs include rapid fever, chills, headache, myalgia, leukopenia, and thrombocytopenia - infects granulocytes. Natural host is the white-footed deer mouse and is carried by deer tick

Clostridium difficile (C. diff) in colon

Antibiotic associated diarrheas - pseudomembranous colitis: cytotoxins kill enterocytes; white membrane ulcer in epithelium. Risk factors include use of PPIs, older age, antibiotic therapy, recent hospitalization, chemotherapy, chronic kidney disease, and feeding tube. Treated with fecal transplant

Helicobacter pylori (H. pylori)

Associated with gastric and duodenal ulcers/gastritis. Uses flagella to get away from stomach acid, uses urease to break down urea to NH4 and CO2, reacts with H20 to form bicarb, increasing stomach pH. The cytotoxin and ammonia can destroy mucus-producing cells, exposing underlying connective tissue to stomach acid, leading to inflammation and/or bleeds

Streptococcus agalactiae: group type

B

Moraxella catarrhalis in respiratory tract

Bronchitis and sinusitis in children, major cause of otitis media, bronchopneumonia happens in older adults

Proteus vulgaris and mirabilis

Commensal - Urinary tract infections - urease cleave urea in urine influencing pH and causing formation of stone - highly motile

Kiebsiella pneumoniae

Commensal - Urinary tract infections and pneumonia, no flagella and found in large intestines, soil, and water

Streptococcus bovis: group type

D

Corynebacterium diphtheriae of the throat/respiratory tract

Diphtheria: signs and symptoms include sore throat, fever, exudative pharyngitis with thick pseudomembrane - can cause advanced toxigenic symptoms like congestive heart failure, paralysis of cranial nerves, and death. can be transmitted by inhalation or skin contact. colonized in throat. treated with diphtheria antitoxin and antibiotics. has an effective vaccine

Bacteroides fragilis

Endogenous infection: occurs intra-abdominally from surgery/trauma and causes abscess in the colon. Is an aerobic, non-spore forming rod and predominant organism in colon

Campylobacter jejuni

Enterocolitis - foul-smelling, watery diarrhea accompanied by blood and severe abdominal pain. Transmitted through fecal-oral route in food, such as poultry and unpasteurized milk

Chlamydia trachomatis in the birth canal/vagina/rectum/penis - trachoma

Eye infection in infants which is the leading cause of blindness worldwide. Spread by flies and hand-to-eye contact

Clostridium botulinum in neurons

Floppy baby syndrome (hypotonia) botulinum toxin can pass from gut into circulation where it is taken up by axons which block neurotransmitters causing flaccid paralysis of striated muscles

Clostridium botulinum in GI tract

Food poisoning - found in canned foods and is heat labile with a high mortality

Staphylococcus epidermidis: skin/prosthetics/artificial joints

Forms biofilm that is a virulence factor. Capsule surrounding the pathogen is also a virulence factor which helps with adherence and avoiding antibodies

Haemophilus influenzae

Gram negative rod - Endotoxin and antiphagocytic capsule are virulence factors. causes otitis media, sinusitis, bronchitis/pneumonia, meningitis, and epiglottitis by colonizing upper respiratory tract mucosa

Legionella pneumophila

Gram negative rod - Facultative, aerobic intracellular pathogen that normally lives in soil and water and is transferred through water droplets. It causes Legionnaire's disease, a serious type of atypical pneumonia

Bordetella pertussis

Gram negative rod - Pertussis (whooping cough) caused by attachment of bacteria to ciliated epithelium in upper respiratory tract and kills ciliated cells

Escherichia coli (E. coli)

Gram negative rod that causes pneumonia, meningitis, diarrhea, dysentery, hemolytic uremic syndrome, and most UTIs. Most abundant facultative anaerobe in colon/feces with 3 antigens (O - cell wall, H - flagella, and K - capsule)

Streptococcus

Gram positive, cocci-shaped, facultative, coagulase negative

Staphyloccocus

Gram-positive, cocci shaped facultative anaerobes

Yersinia pestis (plague)

Highly infectious with high person-person spread. responsible for bubonic (caused by flea bites and has swelling buboe) and pneumonic plague (spread by bacteria through blood to cause plague meningitis)

Enteropathic E. coli (EPEC)

Infant diarrhea - attaches to small intestinal mucosal cells and destroys microvilli

Neisseria meningitidis in respiratory tract

Meningitis - can be transmitted through inhalation and spreads to the meninges and brain. Meningococcemia is a rare case of pathogen infection and can see also necrosis of skin. Polysaccharide capsule is target for vaccine. Endotoxin (shock LPS), pneumonia, and arthritis.

Pseudomonas aeruginosa

NOT commensal and is aerobic and oxidase positive. Nosocomial UTI, pneumonia in patients with cystic fibrosis, infections of the skin, eye, and outer ear, common in hot tubs

Enterohemorrhagic E. coli (EHEC)

Produces Shiga-like toxin, released upon the cell's lysis, Most outbreaks are due to serotype O157:H7, Cattle are the main reservoir, Causes hemorrhagic colitis and hemolytic uremic syndrome, infects large intestine

Treponema pallidum

STI - Syphilis: spirochete. Disease characterized by sores around the genitalia or at original site of infection. Divided into primary, secondary, and tertiary syphilis

Ureaplasma urealyticum in genitourinary tract

STI - causes 20% of non-gonococcal urethritis

Mycoplasma hominis in genitourinary tract

STI - urethritis, infrequent cause of pelvic inflammatory disease

Shigella

Shigellosis (bacillary dysentery) symptoms similar to EIEC from E. Coli - cellular invasion via endocytosis allows bacteria to enter bloodstream and infect other endothelial cells. Low ID50 (<100)

Borrellia burgdorferi

Spirochete that causes Lyme disease - most common vector borne disease in US. Characterized by erythema chronicum migrans (bullseye rash) and flu like symptoms. Can have progressive CNS response

Pasteurella multocida

Spreading cellulitis wound infection from dog and cat bites

Catalase test differentiates between

Staphylococcus and Streptococcus

Coagulase test differentiates between

Staphylococcus aureus and other staphylococcus bacteria

Clostridium tetani in nervous system

Tetanus (lockjaw) caused by soil infecting wounds, allowing entry of pathogens into blood circulation. Pathogen produces tetanus toxin that affect the nervous system blocking release of inhibitory transmitters, causing irreversible contractile signal, causing muscular spasms

Staphylococcus aureus toxinoses - vagina/nose

Toxic Shock Syndrome Toxin - produced locally and exerts systemic effect via blood stream resulting in super antigens that stimulate T cells to release cytokines leading to rash, shock, and organ failure

Enterococcal faecalis & faecium

UTIs, bacteremia, wound infections, and endocarditis

Listeria fogenes in reproductive tract

abortion in pregnant women

Staphylococcus aureus: pyogenic pathology of skin - furuncle

abscess causing pus filled inflammation of hair follicles which can lead to cellulitis

Mycobacteria

acid fast, aerobic bacilli, cell wall containing mycolic acid, rigid filamentous

Bacillus anthracis of the skin

anthrax: darkening of infected spots on skin surface due to vesicle development - can be transmitted through the air

Mycoplasma pneumoniae in respiratory tract

atypical pneumonia lower respiratory tract infection: bacterial attachment to epithelium leads to inhibition of ciliary motion and necrosis of epithelium. symptoms include headache, fever, and non-productive cough - only infects humans

Listeria fogenes in blood/heart

bacteremia that can lead to endocarditis

Streptococcus pneumoniae, listeria, neisseria meningitides, haemophilus influenzae, escherichia coli

bacteria that cause meningitis

Staphylococcus aureus, streptococcus pyrogenes, streptococcus pneumoniae, streptococcus agalactiae, neisseria meningitides, moraxella catarrhalis, chlamydia pneumoniae, chlamydia psittaci, mycoplasma pneumonia, haemophilus influenzae, legionella pneumonphila, escherichia coli, klebsiella pneumoniae, pseudomonas aerugionsa, francisella tularensis

bacteria that cause pneumonia

Streptococcus pneumoniae of nasopharynx/respiratory tract - pneumococcal pneumonia

capsules and adherence on pathogen inhibit lysis by phagocytes and have different antigen types - complement system NOT active

Streptococcus pyrogenes: toxinoses of skin - scarlet fever

caused by erythrogenic exotoxins - symptoms include red sunburn-like rash on neck, trunk, and extremities

Streptococcus pneumoniae of meninges (brain and spinal cord) - meningitis

causes adherence of pathogen to endothelial cells of the meninges. occurs mostly at ages >30 years and 1-23 months

Bartonella henselae

causes cat-scratch disease and bacillary angiomatosis, Cat-scratch fever is characterized by low fever and lymphadenopathy

Enteroinvasive E. coli (EIEC)

causes diarrhea with pus similar to shigella with inflammatory cells in the stool (dysentery) - in large intestine

Streptococcus agalactiae

causes meningitis, pneumonia, and bacteremia in newborns as they pass through birthing canal. 30% of mothers are Group B strep positive

Staphyloccocus saprophyticus: vagina/ureter/rectum

causes urinary tract infections (UTIs)

Vibrio cholerae

cholera - toxin causes active secretion of ions and water into small intestine by activating adenyl cyclase and increasing cAMP - leads to shock, electrolyte loss, and dysentery. High ID50 (10^6)

Staphylococcus aureus: pyogenic pathology of lung/respiratory tract - necrotizing pneumonia

complicated form of pneumonia that occurs due to development of necrosis within lung tissue

Streptococcus pyrogenes: toxinoses of skin - necrotizing fasciitis (flesh-eating bacteria)

death of soft tissues that spreads rapidly and mostly affects the limbs

Clostridium perfringens in connective tissue - virulence factors

degradative enzymes facilitate spread and liquefy tissue while the alpha toxin kills cells and increase capillary permeability

Streptococcus mutans in teeth

dental cavaties

Streptococcus bovis of the heart

endocarditis

Streptococcus mutans in blood/heart

endocarditis and bacteremia which enters bloodstream during dental procedures

Staphylococcus aureus toxinoses - skin

exofoliatin - causes scalded skin syndrome characterized by skin blistering and epidermolysis (separation of epidermis)

Gram-negative rods of enteric tract (Enterobacteriaceae)

facultative anaerobes that primarily live in the colon and possess both endotoxins and exotoxins

Listeria fogenes in GI tract

food poisoning - can grow at 4 degrees celsius. large outbreaks occurred due to contaminated processed foods

Salmonella enterica

food poisoning - major cause from poultry, eggs, and pork. Gastroenteritis is a localized disease caused by penetration of mucosal cells by bacteria. Symptoms are nausea, diarrhea, and vomiting. Invades epithelial cells of the small intestine with 1500 serotypes

Bacillus cereus of the GI tract

food poisoning: emetic form is heat stable enterotoxin found in warmed rice while diarrheal form is found in meats and veggies and is heat labile

Clostridium perfringens in GI tract - food poisoning

found in meat and gravy and can grow in reheated foods. Enterotoxin produced in small intestines after sporulation that is heat resistant. Low mortality. Symptoms include diarrhea and cramps 8-20 hours after ingestion

Vibrio parahaemolyticus

gastroenteritis from raw seafood; symptoms similar to cholera

Chlamydia trachomatis in the birth canal/vagina/rectum/penis - urethritis/prostatitis/proctitis

in men. symptoms include clear, watery discharge from the penis

Chlamydia trachomatis in the birth canal/vagina/rectum/penis - cervicitis/salpingitis

in women is a major cause of infertility

Clostridium perfringens in connective tissue - gas gangrene

infection of severe and open wounds that can spread through spores and invade muscle and other tissues. symptoms include blackened, swollen skin or tissue

Staphylococcus aureus: pyogenic pathology of bone/joint: osteomyelitis

infection of the bone that can spread to blood tissue; dead bone

Streptococcus pyrogenes: pyogenic pathology of skin - cellulitis

infection of the deeper tissues

Staphylococcus aureus: pyogenic pathology of heart - endocarditis

infections of inner lining of the heart (endocardium) due to spread of pathogen in the blood

Mycoplasma

lack cell wall, cholesterol bilayer, pleomorphic, unusual self-replication, very small genome, strict dependence on host

Mycobacterium leprae

leprosy (Hansen's disease) - rare in US, slow growing, contracted by prolonged skin contact, can cause nerve damage and limb deformities

Staphylococcus aureus: pyogenic pathology of skin - mastitis

localized infection of lobules of breast tissue that results in swelling, redness, and warmth

Staphylococcus aureus: pyogenic pathology of skin - boils

lots of pus, can cause pain, walled off infection

Listeria fogenes in brain/spinal cord

meningitis: major cause in newborns, elderly, or immunocompromised patients with high mortality rate

Streptococcus pneumoniae of nasopharynx/respiratory tract - ear (otitis media)

most common cause of ear infections in children and is multifactorial

Clostridium perfringens in connective tissue - myonecrosis

necrosis (cell death) of muscle tissues caused by pathogen invasion

Staphyloccocus saprophyticus: coagulase test

negative

Staphylococcus epidermidis: coagulase test

negative

group B strep, E. coli, listeria monocytogenes, strep pneumoniae

neonatal or elderly meningitis

Listeria

no anaerobic growth, no spore formation, no exotoxins

Corynebacterium

no anaerobic growth, no spore formation, yes exotoxins

Bacillis

no anaerobic growth, yes spore formation, yes exotoxins

Neisseria gonorrhoeae in genitourinary tract/oral cavity/rectum - gonorrhea

no capsule - pyogenic STI that causes urethritis, pharyngitis, cervicitis, proctitis, conjunctivitis and can lead to pelvic inflammatory disease. Majority of women are asymptomatic.

Neisseria gonorrhoeae in genitourinary tract/oral cavity/rectum - acute salpingitis

no capsule - vaginal and cervical infection; atopic pregnancy

Streptococcus pneumoniae: group type

none (does not possess group antigens)

Streptococcus pyrogenes: immune-related (post-infection) of blood/vascular system - rheumatic fever

occurs when anti-M antibodies cross-react with heart and joint tissues causing fever, rash, carditis, and arthritis

Streptococcus pyrogenes: immune-related (post infection) of blood/vascular system - glomerulonephritis

occurs when antigen-antibody complexes accumulate on the glomerular of the kidneys causing hypertension, edema of the face and ankles, and bloody urine (Type III hypersensitivity)

Streptococcus pyrogenes: pyogenic pathology of lungs

pneumonia

Chlamydia psittaci in respiratory tract

pneumonia (parrot fever)

Acinetobacter in respiratory tract

pneumonia, sepsis, and urinary tract infections, mostly affects immunocompromised patients and is found in water

Staphylococcus aureus: coagulase test

positive

Streptococcus pyrogenes: toxinoses of skin - strep toxic shock syndrome

produced locally and exerts systemic effect via blood stream resulting in super antigens that stimulate T cells to release cytokines leading to rash, shock, and organ failure

Chlamydia

rigid cell wall

Staphylococcus aureus toxinoses - GI tract

secretion of a heat-labile enterotoxin that causes food poisoning. symptoms include diarrhea and vomiting

Streptococcus pyrogenes: pyogenic pathology of skin - erysipelas

skin inflammation caused by degradative enzymes such as nucleases and hemolysins

Staphylococcus aureus: pyogenic pathology of soft tissues - abscess

soft tissue abscess in the muscle tissue or eye

Staphylococcus aureus: pyogenic pathology of skin - impetigo

sore spots surrounding red skin which can be caused by wound infections

Streptococcus pyrogenes: pyogenic pathology of skin - impetigo

sore spots surrounding red skin which can be caused by wound infections

Streptococcus pyrogenes: pyogenic pathology of throat - pharyngitis

strep throat characterized by sore and red spots on the throat

Chlamydia pneumoniae

transmitted by respiratory secretion - atypical pneumonia or bronchitis. causes 10% of pneumonias and by age 20, 50% have antibodies

Enterotoxigenic E. coli (ETEC)

traveler's diarrhea, watery diarrhea, low-grade fever, nausea, and vomiting. infects small intestine

Mycobacterium tuberculosis in respiratory tract/blood

tuberculosis - white plague or consumption. severe cases can cause death by years of coughing, fever, and weight loss

Streptococcus mutans: group type

viridans

Mycobacterium avium-intracellulare in respiratory tract

virulent form of tuberculosis infection occurs commonly in severely immunosuppressed patients - most common systemic bacterial infection