Microbiology Flashcards
Lactose fermenters turn _____ on MacConkey agar
Pink
What are the only 2 lactose fermenting bacteria?
- Klebsiella pneumonia
2. E. coli
What are the 3 bacterial that cause HUS?
- Shigella
- E. coli
- campylobacter
This is a non-spore forming, gram (+) rod often transmitted by dairy products
Listeria monocytogenes
How does shigella invade the body?
fecal-oral, invades though M-cells
Aside from chlamydia, what Enterobacteriaceae can cause reactive arthritis?
- Shigella
- Salmonella
- Yersinia
- Campylobacter
What two Enterobacteriaceae can carry the “shiga toxin”?
- Shigella
2. E. coli
Shigella, Salmonella and Yersinia carry a type ___ secretion system
type III
How does Shigella cross from the invaded M cell to neighboring epithelial cells?
uses host M cell’s actin filaments for propulsion
What virulence factor is the trigger for HUS?
the SHIGA toxin
Which Enterobacteriaceae can cause neutrophiles in the stool?
- Shigella
- Salmonella
- Campylobacter
Use antibiotics for infection with (shigella/E coli)
Shigella only, Abx with E. coli can precipitate HUS
Which turns black on Hektoen agar? why? (E. coli/ Salmonella/Shigella/Yersinia)
salmonella, is H2S positive
What is the Infectious dose for salmonella? Shigella?
Salmonella, 100,000, is acid labile
shigella, 100, is acid stable
Which invade macrophages? (E. coli/ Salmonella/Shigella/Yersinia)
salmonella
to some extent shigella
Which is acid-labile? Acid stable? (shigella/salmonella)
Shigella is acid stable: survives stomach acid
Salmonella is acid labile: stomach acid kills, need a high infectious dose
What causes typhoid fever?
Salmonella typhi
What organ does Salmonella form a chronic carriage?
the Gallbladder
Heterozygosity for the _______ allele confers protection against typhoid fever
CTFR, cystic fibrosis
Rose spots appear on the stomach with (E. coli/ Salmonella/Shigella/Yersinia)
salmonella
rose spotted bib
Salmonella + Sickle cell anemia –> _________
Osteomyelitis
Which causes “false appendicitis”? (E. coli/ Salmonella/Shigella/Yersinia)
Yersinia enterocolitica, painful swollen lymph node
How can you identify listeria under the microscope?
‘Tumbling Motility’ is characteristic
Why might pregnant women be advised to avoid soft cheeses?
Risk of Listeria infection
How do you treat a listeria infection?
Ampicillin (can add gentamicin for week 1)
Which enteric agent makes ‘actin rockets’ to propel through multiple cells?
Listeria
Shigella uses IcsA to polymerize actin filaments for propulsion as well
What enteric agent can escape the GI and proliferate in the placenta and attack the fetus?
Listeria
Vaginal transmission of Listeria during birth can cause ________
neonatal meningitis
Which has LPS? (gram +/ gram -) bacteria
Gram (-)
Is listeria gram + or - ?
Gram +, purple
What should you put in the IV of someone with severe cholera infection?
Lactated ringer solution
Which causes rice water diarrhea? what about the others? (V. cholera/ V. parahaemolyticus/ V. vulnificus)
Severe rice water diarrhea: V. cholera
Various diarrhea: V. parahaemolyticus
Rarely known for diarrhea: V. vulnificus
which is known for shellfish contaminated wounds? (V. cholera/ V. parahaemolyticus/ V. vulnificus)
shellfish wounds: V. vulnificus
At what temp does campylobacter grow? what is a chicken’s body temperature?
campy grows at 42C, same as a chicken
what lab breath test can be done for Helicobacter pylori?
urea breath test, H. pylori is urease (+)
What bacteria species is ass. with eating undercooked seafood? how do you expect it to gram stain?
V. cholera and V. parahaemolyticus are gram - rods
what is the leading cause of severe diarrhea in infants and children?
rotavirus
How long the diarrhea last with rotovirus? norovirus?
rotavirus: 5 days
norovirus 2 days
What are the 3 presentations of Coxsackie A virus?
- herpangina
- hand and mouth
- acute hemorrhagic conjunctivitis
What is the presentation of Coxsackie B virus?
- Dilated cardiomyopathy
2. pleurodynia
What is the cause of “beaver fever”
giardia, infects mammals
What are the symptoms of giardia infection?
flatus, weight loss, diarrhea greasy stool w/ odor, floating stool
What is the most likely outcome of a giardia infection? What is the Rx?
clearance in 60% of cases
Rx: tinidazole, like metronidazole
Contaminate water supply from cow/calf run-off, causes diarhea 10-14 days then resolves, can be sever in AIDS/immunocompromised
Crytosporidium parvum
How do you prevent Crytosporidium parvum? How do you treat it?
Prevent by water filtration
Treat by Nitazoxanide (or spiramycin)
Which parasite penetrates the mucosa of the colon and can make hepatic and renal cysts?
Entamoeba histolytica
What is the treatment for Entamoeba histolytica?
Metronidazol (paramycin and iodoquinol to eliminate cysts)
From what meat can you get:
taenia solium
taenia saginata
diphyllobothrium latum
taenia solium: pork
taenia saginata: beef
diphyllobothrium latum: fish
Which can cause brain and muscle lesions:
taenia solium
taenia saginata
diphyllobothrium latum
taenia solium: pork
Which can cause B12 deficiency and pernicious anemia
taenia solium
taenia saginata
diphyllobothrium latum
diphyllobothrium latum: fish
What are the S+S of Ascaris lumbricoides?
pulmonary symptoms, eosinophilic pneumonia, intestinal obstruction
Which can cause perianal pruritus? (Ascaris lumbricoides/ Strongyloides stercoralis/ Enterobius vermicularis)
Enterobius vermicularis
Which can be Dx with adhesive tape? (Ascaris lumbricoides/ Strongyloides stercoralis/ Enterobius vermicularis)
Enterobius vermicularis
Which can cause fluctuating eosinophilia with maculopapular rash on the buttock, perineum and thighs
(Ascaris lumbricoides/ Strongyloides stercoralis/ Enterobius vermicularis)
Strongyloides stercoralis
Which is also called “pin worm”
(Ascaris lumbricoides/ Strongyloides stercoralis/ Enterobius vermicularis)
Enterobius vermicularis
Nemetodes, Tremetodes and Cestodes are all ________
helminths
Ascaris lumbricoides, Strongyloides stercoralis, Enterobius vermicularis are all (Cestodes/ Nematodes/ Tremetodes)
Nematodes
T. solium T. saginata and D. Latum are all (Cestodes/ Nematodes/ Tremetodes)
Cestodes
What family of virus is hep C? RNA or DNA?
flavi virus, RNA genome
What is the MC cause of erysipelas?
S. pyogenes