GI Flashcards
what should you distinguish when a pt has a CC of diarrhea?
with or without urgency
what time frame defines acute diarrhea?
less than 2 weeks
what time frame defines chronic diarrhea?
more than 30 dys
what defines a mild diarrhea?
less than 3BMs per day
what defines a moderate diarrhea?
more than 4BMs per day with local sxs
what defines a severe diarrhea?
more than 4 BMs per day with systemic sxs
what is the MCC of acute diarrhea?
infectious process usu. viral and self limited
severe is usu. bacterial in nature
what is the MCC of chronic diarrhea in underdeveloped countries??
chronic infection
what is the MCC of chronic diarrhea in developed countries?
IBS, IBD, Malabsorption
which viruses are a/w non inflammatory diarrhea?
rotavirus
norwalk virus
which protozoa are a/w non inflammatory diarrhea?
giardia (streams, water)
cryptosporidium
cyclospora
what virus is a/w inflammatory diarrhea?
CMV
what protozoa is a/w inflammatory diarrhea?
entamoeba histolytica
what is classic cause of bacillus cereus?
fried rice (causes non inflammatory diarrhea)
which bacteria produce enterotoxins and non inflammatory diarrhea?
ETEC (E. coli) vibrio cholerae (fish)
which bacteria produce cytotoxins and inflammatory diarrhea?
O157:H7 (EHEC)
vibrio parahoemolyticus (fish)
c. diff
which bacteria invade the mucosa and cause inflammatory diarrhea?
shigella Campylobacter jejuni salmonella enteroinvasive E. coli yersinia
what are the pathogenic clues when assessing for diarrhea?
well water/farm ill contacts occupational exposure recent travel pets (reptiles) hobbies recent Hospitalizations and abx use food history
what are key food hx questions when assessing for diarrhea?
unpasteurized milk, apple joice
raw, undercooked meat, fish
why is timing important for diarrhea?
length of time between ingestion and sxs can point to the pathogen
1-6hrs (s. aureus, b. cereus)
8-16 hrs (c. perfringens)
when would you order O&P?
presistent diarrhea foreign travel day care exposure community water outbreak MSM or HIV
when would you consider an endoscopy in a diarrhea pt?
suspected c. diff
suspected ischemic colitis
IBD infectious vs IBD flare
PING
when is abx contraindicated for diarrhea?
suspected or proven EHEC (toxin of bacteria and abx cause renal failure)
when might you give a pt prophylactic abx?
PING pts or with need for prevention while travelling
which medications can cause chronic diarrhea?
SSRIs Cholinesterase inhibitors NSAIDS PPIs Angiotensin II receptor blockers Metformin Allopurinol Colchicine
what is a cathartic screen?
tests for metabolites of laxatives in stool
what is secretory diarrhea?
intestinal mucosa directly secretes fluid and electrolytes into the stool (pushes)
causes normal or decreased osmotic gap
diarrhea will not change with fasting
what is osmotic diarrhea?
malabsorption of ingested substance which pulls water into lumen (substances what to be diluted)
causes an increased osmotic gap
will resolve during fasting
what is the MCC of osmotic diarrhea?
carbohydrate malabsorption
laxative use/abuse
malabsorption syndromes
what are causes of secretory diarrhea?
endocrine tumors
bile salt malabsorption (stimulates colonic secretion)
what osmotic gap would indicate a secretory diarrhea?
50 mosm/kg
what osmotic gap would indicate an osmotic diarrhea?
125 mosm/kg
what is a normal osmotic gap?
50-125 mosm/kg
what are causes of bile salt enteropathy?
drugs infection hyperthyroidism laxative abuse neuroendocrine tumor rectal villous adenoma
what can cause malabsorptive d/o?
celiac sprue small bowel resection carcinoid chronic pancreatitis pancreatic carcinoma
what can cause motility d/o (peristalsis is inhibited and draws more water in and causes diarrhea)?
postsurgical
systemic d/o
IBS
what does a crampy pain usu indicate in GI?
obstruction
what does a steady pain usu indicate in GI?
inflammatory process
where does gall bladder pain radiate to?
right shoulder
what is the test of choice for evaluating RUQ pain?
ultrasound
what is the approach of a GI complaint?
- complaint based
2. disease state based
what does odynophagia imply?
inflammation