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Flashcards in Entero 3 Deck (11):

All vibrios are

curved, gram neg rods, all can grwo on bile salts agar in vitro (selective for SALT TOLERANCE)


Cholera has caused;
for epidemics there is

epidemics and pandemics throughout history, with best preventatives being hygiene (food and water purification);
modestly-effective vaccine


Cholera reservoirs are

humans and ocean microbial communities, primarily Indian ocean but now seen in Gulf of Mexico;
"planktonic" ocean form is source of genetic diversity


Cholera pathogenesis:

fecal-oral transmission, poor survival in stomach acid, so requires high infectious dose, colonizes epi of interior surface (lumen) of small intestine with mucinase and toxin-coregulated pilus (TCP), secretes Choleragen exotoxin enterotoxin, AB subunit signal transduction alterer that can lead to massive watery diarrhea (rice water stool), both IC and interstitial


Choleragen gene carried by

lysogenic bacteriophage CTX; O1 and O139 Ags are markers for infection by CTX (non-CTX V cholerae strains cause sporadic mild disease)


Cholera bacteremia is;
interstitial dehydration diagnosed by

rare, most morbidity and mortality from dehydration and electrolyte imbalance (acidosis, loss of K);
skin-tenting pinch test, treated with IV Lacted Ringer Solution (not just saline - acidosis)


What can help deal with Cholerae or parahaemolyticus?

Rehydration most important, but short course of doxycycline helps shorten the course


Non-cholera vibrio infections associated with; reservoir is;
complicating factors are

gastroenteritis (usually self-limited) and rapid progression cellulitis (life-threatening) from eating or handling raw shellfish;
ocean water that means they are halophiles;
liver or kidney disease, immunodeficiency, iron overload


Diagnose cellulitis by

exam (rapid progression, HEMORRHAGIC BULLAE, seawater-exposed injury), proceed with immediate aggressive surgical care; later, do gram stain and culture, and treat with dual antibiotics!!



Campylobacter are;
reservoir from;
colonizes both;
complications follow;
diagnose by;
treat with

gram neg rods, microaerophilic, ubiquitous;
animals, causes diarrhea, some autoimmune complications;
intestines, destructive IC infection, bloody diarrhea;
bacteremia: Guillain-Barre, reactive arthritis, HUS, meningitis, vascular infection;
microaerophilic culture, gram stain of fecal smear, sigmoidoscopy;
rehydration, add antibiotics if high fever or predisposed to complications (immunosuppressed, pediatric, worsening)


H pylori is related to;
predisposes to;
diagnose by;
treat with

campylobacter, colonizes stomach, expresses urease, irritates stomach lining, attracts massive inflamm infiltrate, destroys local cells, leads to peptic uler;
gastric cancer and MALT lymphoma, and infection much more common than symptoms;
scope, urea breath and/or PCR, biopsy;
combined antibiotics and PPI's