GI LAB Flashcards
On MAC is Salmonella a lactose fermenter?
Salmonella = non lactose fermenter
On MAC is Shigella a lactose fermenter?
Shigella = non lactose fermenter
On MAC is Shiga producing E. Coli (STEC) a lactose fermenter?
Shiga producing E. Coli (STEC) = Lactose Fermenter
On MAC is Vibrio a lactose fermenter?
Vibrio = non-lactose fermenter
On MAC is Campylobacter a lactose fermenter?
Campylobacter = no growth on MAC
Salmonella is oxidase?
Salmonella = oxidase negative
Shigella is oxidase?
shigella = oxidase negative
Shiga producing E. Coli (STEC) is oxidase?
Shiga producing E. Coli (STEC)= oxidase negative
Vibrio is oxidase?
Vibrio = oxidase positve
Campylobacter is oxidase?
campylobacter = oxidase positive
what type of media will Vibrio grow on?
TCBS
how to detect H2S?
via SIM (sulfide indole motility agar)
what organisms produce H2S?
salmonella
what conditions does Clostridium difficile require to grow?
anaerobic sheep blood agar
what organism smells like horse barn?
clostridium difficile
what does Campylobacter need to grow?
CAMPy CVA media (cefoperazone, vancomycin and amphotericin B)
-incubate at 42 degrees celcius in 105 CO2
what is the gram stain and morphology of Clostridium difficile?
C. diff. = gram positive bacilli - anaerobic
what is the gram stain and morphology of Vibrio
Vibrio = curved gram negative bacilli
what is the gram stain and morphology of Campylobacter?
Campy = curved gram negative bacilli
what is the gram stain and morphology of Salmonella?
Salmonella = gram negative bacilli
what is the gram stain and morphology of Shigella?
shigella = gram negative bacilli
what is the gram stain and morphology of STEC?
gram negative bacilli
how to identify Cryptosporidium?
microscopy showing acid fast oocysts
how to identify Giardia?
microscopy showing cysts and trophozoites in stool; prefered method = antigen detection
does Salmonella oxidize and or ferment glucose?
salmonella ferments glucose
does Shigella oxidize and or ferment glucose?
shigella ferments glucose
does Shiga toxin producing E. Coli (STEC) oxidize and or ferment glucose?
Shiga toxin producing E. Coli (STEC) ferments glucose
does Vibrio oxidize and or ferment glucose?
Vibrio ferments glucose
STEC in fermentation of sorbitol?
STEC - does NOT ferment sorbitol - it will ferment lactose
enterics and glucose fermentation?
all enterics are glucose fermentoers
all enteric gram negative bacilli are oxidase?
-negative
what do most species of Vibrio require to grow?
NaCl
what is the consistency of stool that cysts and trophs are found in?
cysts - more solid stools
trophs - watery stools
in giardia what stage is infecive?
the cyst stage is infectious
what is the trophozoite stage in giardia?
the trophozoite stage has flagella and is for feeding and reproduction
what causes C. difficile?
- broad spectrum antibiotics
- recent hospitalization
what causes the problems and symptoms in C. Diff?
- C. Diff is antibiotic resistant and produces spores and it outgrow the normal flora
- pathogenic strains often have toxin A, Toxin B
signs and symptoms of C. diff?
-bloody diarrhea, abdominal pain, fever, higher WBC
how to treat C. diff?
- stop antibiotics
- start oral vancomycin or metronidazole
- avoid antidiarrheals
what is the leading cause of gastric injury with inflammation?
Helicobacter pylori
what can H. pylori cause?
- erythema, nodularity due to patchy inflammation
- gastic or duodenal ulcer
- inflammation of the antrum
gram stain and morphology of Helicobacter pylori?
gram negative bacilli
what forms of hepatitis are acute?
hepatitis A is acute
what forms of hepatitis can causes cirrhosis of the liver?
type B and C
when is biopsy indicated in testing for hepatitis?
to assess chronic viral hepatitis that lasts for than 6 months
what is the most common cause of chronic hepatitis and cirrhosis?
hepatitis C
what does cirrhosis of the liver look like?
nodules
how long does acute diarrhea last for?
less than 2 weeks
how long does persistent diarrhea last for?
2-4 weeks
how long does chronic diarrhea last for?
great than 4 weeks
describe the likely causative agent of acute diarrhea?
viral and bacterial
how to tell the difference of viral and bacterial acute diarrhea based on symptoms?
- viral = self limited
- bacterial = if severe or with fever or bloody stool
describe the likely causative agent of persistent diarrhea?
- less likely bacterial or viral
- can be parasite
a malabsorption of fat causes?
-greasy stools that float in the toilet and smell bad and lots of gas
high volume diarrhea is an issue with what anatomical site?
the small intestine
-less at night and worse after meals
STEC and cholera cause what type of stool?
high volume water diarrhea and dehydration b/c toxins block fluid reabsorption
what 3 things form spores?
- bacillis cereus
- clostridium perfringes
- clostridium difficile
what causes neonatal meningitis
Listeria monocytogenes
what causes Hemolytic uremic syndrome?
STEC
entrobacteria are treated by?
carbabenems