Diarrhea Flashcards
1
Q
normal function of the colon
A
- sodium reabsorbed, potassium secreted in exchange
- patients with diarrhea are hypokalemic
2
Q
normal composition stool water
A
- volume about 100 ml/day
- Na = 40 mEq/L
- K = 90 mEq/L
- osmolality is close to that of plasma = 280 mOsm/L
3
Q
features of osmotic diarrhea
A
- diarrhea stops after fasting
- fecal volume is < 1 L/d
- fecal pH less than 6
- fecal osmolality 280-400
- osmotic gap is above 40-60
4
Q
features of secretory diarrhea
A
- diarrhea continues after fasting
- fecal volume is >1 L/day
- fecal pH >7
- fecal osmolality 260-300 mosm/L
- osmotic gap is <20-40 mosm/L
5
Q
osmotic gap calculation
A
- stool osmolality - 2(Na+K) = osmotic gap
6
Q
infectious or inflammatory causes of diarrhea
A
- enterotoxic organisms
- toxins affect primarily small bowel secretion
- watery diarrhea with cramps, rare fecal PMNs
7
Q
invasive organisms causing diarrhea
A
- colon involved- fecal PMNs prominent
- systemic symptoms are unusual
- most common causes are shigella, salmonella, and campylobacter jejuni (#1 cause of infectious bloody diarrhea)
8
Q
frequent, small volume diarrhea
A
- usually indicates left sided (rectosigmoid) involement
- tenesmus and urgency are common
- blood and mucous are commonly seen
9
Q
large volume, less frequent diarrhea
A
- usually right colonic or small bowel origin
- no tenesmus or urgency
- blood is uncommon
10
Q
fecal leukocytes in infectious enterocolitis
A
- present in shigella, C. jejuni, and invasive E. coli
- absent in food poisoning, giardia, virus, ETEC, amoeba, cholera
11
Q
antibiotic exposure
A
- C. difficile infection
12
Q
drinking water from a river
A
- Giardia
13
Q
appendicitis like symptoms with diarrhea
A
- salmonella or yersinia
14
Q
shigellosis treatment
A
- dont use antimotility drugs when patient has bloody diarrhea
- do not use amoxicillin
- ampicillin, tetracycline, trimethoprim and cipro work
15
Q
virus on cruise ship
A
- Norwallk
- rotavirus in infants and young children
- transmission is fecal oral
