Aerobic gram +/- rods Flashcards
bacillus anthracis
aerobic, G+ spore forming rod capsular polypeptide (poly-glutamic acid) antiphago three exotoxins - protective antigen (PA) edema factor (EF) and lethal factor (LF), treat- ciprofloxacin D: cutaneous anthrax- eschar formation, black (big scab), GI anthrax- ulcers at site of invasion, inhalation anthrax- biothreat, nonspecific signs followed by severe sepsis
bacillus cereus
aerobic, large G+ spore forming rod, ubiquitous in soil worldwide, two enterotoxins D: food poisoning- vomiting and diarrheal forms, Ocular infection- traumatic penetrating injury, severe pulmonary disease- severe anthrax-like pulmonary disease in immunocomp. patients
listeria monocytogenes
aerobic, gram + motile coccobacilli, facultative intracellular pathogen, grows at 4*C, eg contaminated food treat with penicillin or gentamycin D: contaminated food or transplacental spread (can be transferred from mom to baby), neonatal disease- early onset vs late onset meningitis, disease in adult- asymptomatic or flu-like, pregnant women- third trimester utero infection or birth infection
erysipelothrix rhusiopathiae
aerobic, thin, pleomorphic G+ rods in filaments, zoonotic- colonizes swine, turkey, fish- occupational disease in humans (butchers), penicillin to treat D: erysipeloid- painful, puritic inflame skin lesion at time of trauma, generalized cutaneous disease- diffuse, septicemia leading to endocarditis uncommon
corynebacterium diphtheriae
aerobic, pleomorphic G+ rods, diptheria toxin- A-B toxin inactivates EF-2, special media needed to grow it (cysteine- tellurite agar) vaccine- diphtheria toxoid D: resp. diphtheria- exudative pharyngitis evolving to pseudomembrane, release of toxin to produce myocarditis and neurotox. cutaneous diphtheria- chronic, non-healing ulcer following contact with infected person
Escherichia coli (pathotypes)
G- fermentative rod, normal flora of GI tract, 5 different pathogenic groups with distinct toxins D: gastroenteritis- five major groups with distinct sites of action, symptoms and virulence factors, UTI, neonatal meningitis, septicemia
salmonella enterica
g(-) non-fermenting rod, most infections via contaminated food (poultry or eggs), over 2500 O serotypes, Serovars Typhi and Paratyphi highly adapted to hyumans
D: Gastroenteritis: infectious dose lower if reduced gastric acidity, septicemia, enteric fever (produced by s. typhi, asymptomatic colonization- usually gallbladder, carrier for infection by s typhi and s paratyphi
shigella spp.
G-, non fermenting rod
four species: sonnei, flexneri, dysenteriae, boydii
shiga toxin damages intestinal epi– A-B toxin, human only reservoir
D: shigellosis- gastroenteritis, 450,000 cases per year in US- watery diarrhea caused by enterotoxin, abdomina cramps, fever and bloody stools caused by invasion of colonic mucosa
asymptomatic carriers: reservoir
Yersinia spp.
G- rod, zoonotic– rats, squirrels, rabbits, and domestic animals
Y. pestis– flea vector
enormous historical importance: 3 major pandemics
D: THE PLAGUE- bubonic spread by fleas, pneumonic spread via aerosol (much worse), Y. entercolitica and Y. pseudotubercolosis- enterocolitis following ingestion fo infected meat, milk or water
Klebsiella pneumoniae
gram (-) fermentative rod, encapsulated, antiphagocytic, carbapenem-resistant K. pneumoniae (CRKP)- carbapenemase
D: pneumonia- usually patients with impaired pulmonary defense (diabetes, alcoholism, malignancy COPD), bloody mucoid sputum, UTI, sepsis
Proteus mirabilis
G - rod, urease positive, motile- swarmer on bacteiral plates, urease hydrolyzes urea to ammonia, making urine alkaline–> leads to Kidney stones (struvite crystals)
D: UTI with crystal formation
serratia marcesens
gram neg rod, Red pigment, ubiquitous in damp areas of environment (aka hospitals)
D: nosocomial infection in neonates and compromised patients, UTI, resp. tract infection, wound infection
aeromonas spp.
gram (-) rod, >20 species, ubiq.to fresh and brackish water
D: diarrheal disease in otherwise helathy people- contam. food or water, wound infection-traumatic injury and exposure to contaminated water (katrina), opportunistic systemic disease- in those with hepatobiliar disease or malignancy
V. cholerae
Curved bacillis, G-, Aero, requires salt
Cholera toxin that interacts w/ Gprotein that regs adenylate cyclase
D:Diarrhea w/ rice water stools and vomitting
V. parahaemolyticus
Curved bacillis, G-, Aero, requires salt
Most common gastroenteritis in SE asia and from shellfish in US
Gastroenteritis, Wound infection
