Clin - Diarrhea Flashcards
describe the bristol stool chart
1: separate hard lumps
2: sausage shaped but lumpy
3: sausage but with cracks on surface
4: sausage or snake, smooth
5: soft blobs
6: fluffy pieces w/ ragged edges
7: watery
duration of acute and chronic diarrhea
acute: less than 2 weeks
chronic: more than 4 weeks
compare inflammatory and non-inflammatory acute diarrhea
inflammatory: blood or pus, fever, invasive or toxin producing bacteria, need stool culture
non-inflammatory: watery, non bloody, mild, virus or non-invasive bacteria
most common cause of acute diarrhea
90% is infectious, 75% of that is viral
most common cause of noninfectious acute diarrhea
1) medications
- most frequently antibiotics
2) artificial sweeteners
- sorbitol, chewing gum
antibiotic that commonly causes antibiotic-associated diarrhea
amoxicillin-clavulanate (augmentin)
top 3 causes of chronic diarrhea
1) medications
2) IBS
3) lactose intolerance
what symptoms are inconsistent with medications causing chronic diarrhea and warrant further evaluation
1) nocturnal diarrhea
2) weight loss
3) anemia
4) positive fecal occult blood test
compare osmotic gap between osmotic diarrhea and secretory diarrhea
osmotic: increased stool osmotic gap (50-75)
secretory: normal stool osmotic gap
sx osmotic diarrhea
abd distention, bloating, flatulence due to increased colonic gas production
most common causes osmotic diarrhea
1) medications
2) disaccharidase deficiency (lactose intolerance)
3) laxative abuse
4) malabsorption syndromes
sx secretory diarrhea
high volume watery diarrhea (>1L day)
- hyponatemia
causes of secretory diarrhea
1) endocrine tumors (zollinger ellison, carcinoid syndrome VIPoma)
2) bile salt malabsorption (ileal resection, crohn ileitis)
3) factitious diarrhea (laxative abuse)
4) villous adenoma
what is the sudan stain used for
qualitative staining for fat to test to malabsorption disorders
diagnostic study for most patients with chronic persistent diarrhea
colonoscopy with mucosal bipsy
what diagnostic test is performed when suspected a small intestinal malabsorptive disorder
upper endoscopy with small bowel biopsy
what fecal elastase level indicates pancreatic insufficiency (which could be causing chronic diarrhea)
less than 100 mcg/g
what breath test is used in testing for carbohydrate malabsorption (lactase deficiency)
hydrogen breath test
what diagnostic study will localize neuroendocrine tumors if present
somatostatin receptor scintigraphy
what serology test tests for VIPoma
vasoactive intestinal peptide (VIP)
what serology test tests for medullary thyroid carcinoma
calcitonin
what serology test tests for zollinger ellison syndrome
gastrin
what serology test tests for carcinoid tumor
urinary 5-hydroxyindoleacetic acid (5-HIAA)
medications that are common offenders in mediation induced diarrhea
1) cholinesterase inhibitors
2) SSRIs
3) angiotensin II receptor blockers
4) PPIs
5) NSAIDs
6) metformin
7) allopurinol
common pathophysiology of IBS
visceral hyperalgesia to mechanoreceptor stimuli
what psychological disturbances are associated with IBS
depression, hysteria, OCD
what are the alarm symptoms associated with IBS
1) acute onset of sx
2) nocturnal diarrhea
3) severe constipation or diarrhea
4) hematochezia
5) weight loss
6) fever
7) FMHx of CA
ROME IV criteria is used to diagnose what dz
IBS
diagnostic criteria for IBS
chronic > 6 months for diagnosis, at least 3 months for it to be on a differential
describe the ROME IV criteria for IBS
recurrent abd pain, on average, at least 1 day per week in the last 3 months, associated with 2+ of the following:
1) related to defecation
2) associated w/ change in frequency of stool
3) associated with change in appearance of stool
what is the FODMAPS diet for IBS
fermentable oligosaccharides, disacchardies, monosaccharides, and polyols
what pathogens are associated with CHRONIC infectious diarrhea
protozoans: giardia, e. histolytica, cyclospora
intestinal nematodes: strongyloidiasis stercoralis
bacteria: c. diff
most common antibiotics that increase risk for C. diff
1) ampicillin
2) clindamycin
3) 3rd gen cephalosporins
4) fluoroquinolones
etiologic agents for microscopic colitis
1) NSAIDs
2) PPIs
3) low dose aspirin
4) SSRI
5) ACEI
6) beta-blockers
characteristics of malabsorption syndromes
1) weight loss
2) osmotic diarrhea
3) steatorrhea
4) nutritional defiicency
SIGNS of malabsorption
1) loss of muscle mass or subq fat
2) pallor due to anemia
3) vitamin K deficiency
4) hyperkeratosis
5) osteomalacia
6) neurologic signs due to vitamin B12
sx of malabsorption
1) diarrhea
2) steatorrhea
3) weight loss
4) abd distension
5) weakness
6) muscle wasting
elevated fecal fat
malabsorption syndrome
extraintestinal features of celiac dz
1) fatigue, depression
2) iron deficiency anemia
3) osteoporosis
4) short stature
5) delayed puberty
6) amenorrhea
7) reduced fertility
8) dermatitis herpetiformis
what scan should you do on celiac pts to screen for osteroperosis
dual-energy x-ray densitometry
sx of pancreatic insufficiency causing chronic diarrhea
1) steatorrhea
2) weight loss
3) gaseous distention and flatulence
causes of bile salt malabsorption
1) bacterial overgrowth
2) massive acid hypersecretion
3) medications that bind bile salts
signs of bile salt malabsorption
1) bleeding tendencies
2) osteoporosis
3) hypocalcemia
4) watery secretory diarrhea
periodic acid schiff (PAS) test positive for macrophages with characteristic bacillus
whipple dz
what type of diarrhea is common in the elderly
overflow diarrhea from fecal impaction
describe fecal incontinence
neuromuscular disorder or structural anorectal problems causing involuntary discharge of rectal contents
what is pseudodiarrhea
frequent passage of small volumes of stool
how to diagnose fecal impaction
DRE
chronic use of laxatives can lead to what endoscopic finding
melanosis coli
- benign hyerpigmentation of colon
