Cholera Flashcards
which pathogen causes cholera?
bacteria -> v. (vibrio) cholerae
what kind of disease does the cholera bacteria cause? what is the main symptom?
gastroenteritis, watery diarrhea
why can cholera be lethal?
dehydration and electrolyte imbalances
what kind of bacteria is v. cholerea: gram + or -? shape? does it have a flagella?
gram negative, curved with flagella
via what route is cholera transmitted?
fecal -> oral
- consuming untreated sewage water
- poor hygiene
consumption of what can lead to cholera?
consuming untreated sewage water (or anything that comes in contact with it, e.g. raw or undercooked fish)
cholera: who are particularly at risk for a severe infection?
people with
- low gastric acidity
- 0-blood type
what does v. cholera do in the stomach? (2 things) why?
shuts down protein production to conserve energy
1) conserve energy & nutrients
2) survives acidic environment
what does the v. cholerae do with its flagella in the intestine? (3 things)
1) move towards intestinal walls 2
2) propel through mucus layer
3) attach to villi
what does v. cholerae do when on top of the villi of endothelial cells? (2 things)
multiply, secrete toxins
do cholera bacteria themselves enter enterocytes? do their toxins enter enterocytes?
bacterium doesn’t, but toxins do!
do all cholera bacterial strains cause symptoms? what does it need to produce to cause symptoms?
no
it needs to produce cholera enterotoxin
what is the effect of cholera enterotoxins on the enterocyte wall? (2 effects)
1) production of more chloride channels -> more secretion of chloride into the lumen
2) inhibit channel that let sodium & chloride into cells
what is the effect of more chloride & sodium inside the intestinal lumen?
attracts water -> diarrhea
what are the 2 main symptoms of cholera?
watery diarrhea & vomiting
does cholera cause fever?
no
does cholera cause pain and cramping?
no
how long is incubation time of cholera?
2-3 days
how fast can a patient get dehydrated and depleted of electrolytes after the first bout of diarrhea and vomiting?
4-12 hrs
what are the symptoms of severe hydration?
- disorentiation
- swollen tongue
- dry mouth
- sunken eyes
- cold, clammy skin
- shriveled dry hands & feet
what can you see in the poo of someone with cholera?
white flecks of mucus (looks like rice)
which electrolytes get secreted/lost into the intestinal lumen during cholera?
Na, K, Cl, bicarbonate
which electrolytes get attracted by more sodium and chloride in the intestinal lumen?
K and bicarbonate
low levels of bicarbonate (HCO3) in the blood -> leads to what?
metabolic acidosis & kussmaul breathing
low levels of potassium in the blood -> leads to what?
muscle cramps, abnormal heart rhytms
low levels na Na & Cl in the blood -> leads to what?
headaches, poor balances, disorientation, seizures, coma
how to diagnose cholera?
stool culture
treatment of mild-moderate cholera?
how fast can the diarrhea resolve?
replace lost water & electrolytes with rehydration salts
3-7 days
treatment of extreme cholera? (on top of rehydration)
antibiotics
stool sample can help determine which one
