2.13 Diarrheal Diseases Flashcards
Medical definition of diarrhea?
Stool weight over 300g (or ml)
Increases frequency and decreased consistency of bowel movements
How would you characterize the MAJORITY of acute diarrhea?
Less than two weeks
Mild and self limiting
How can acute diarrhea be life threatening?
Severe depletion of body fluids = profound dehydration
What characterizes inflammatory diarrhea (dysentery)?
Fever, bloody diarrhea, severe abdominal pain
What are diarrhea red flags?
Inflammatory diarrhea
Six or more unformed stool in 24 hrs
Hospital acquired
+ Patients that are frail/older, systemic illness , and immunocompromised
Most common causes of acute diarrhea?
Bacterial toxins, infectious agents, and drugs
Clinical findings for non-inflammatory diarrhea?
Fecal leukocytes and blood absent (-FLT)
More common and usually Viral
Tends to be cvoluminous
Small bowel (periumbilical pain, bloat, nausea, vomit)
Clinical findings of inflammatory diarrhea?
Fecal leukocytes and RBCS may be present
Bloody diarrhea
Fever, left lower quadrant (colon) cramps, urgency, tenesmus
Invasive orgs + toxins cause
How does the phrase “Silly Sally Eats Your Cake and Cookies” help you remember your invasive organisms that can lead to inflammatory diarrhea?
Shigellosis (Shiga toxin), Salmonellosis, Entamoeba histolytic, Yersenia, CMV, & Campylobacter
+CDiff
If positive for FLT, what other labs could you get?
- Ova and parasites
- Rectal swab/cultures (sex active proctitis suspicion)
- C Diff toxin assay (hospital/antibiotics)
Diet treatment protocol for diarrhea?
Oral fluids - carbs and electrolytes
Avoid high fiber foods, fats, caffein, alcohol, and milk products
When to use med treatment for diarrhea?
Only non-inflammatory
BUT NO opioids or anti diarrheal drugs for patients with bloody diarrhea, high fever, or systemic toxicity
What is a common opioid agent used to treat diarrhea by decreasing stool number/liquidity and control fecal urgency?
Loperamide
How does loperamide work?
Inhibits peristaltic activity by acting directly on circular and longitudinal muscles of intestinal wall
When do you consider antibiotics to treat diarrhea?
Moderate to sever fever, tenesmus, bloody stools, FLT +, immunocompromised people
Most common antibiotics to treat C diff?
Vancomycin and Fidaxomicin
Persistent diarrhea?
> 2 weeks but less than 4 weeks
“Acute diarrhea that tends to last longer”
At what point is it considered chronic diarrhea?
> 4 weeks
What should you exclude before a big work up for diarrhea?
- Medications (caffeine + laxative abuse)
- Chronic infections (parasites)
- Irritable Bowel Syndrome*
Medications that can cause diarrhea?
“A SON CAMP”
Angiotensin II blockers
SSRIS
Orlistat
NSAIDS
Cholinesterase inhibitors
Allopurinol
Metformin/Macrolides
PPI
Osmotic diarrhea is characterized by?
Colonic gas production (bloating, flatulence, distention)
Resolved by fasting
Malabsorption syndromes?
Osmotically active substances that would be normally absorbed aren’t (ex. Lactose, glucose)= weight loss, nutrition deficiencies, steatorhhea
High volume watery diarrhea >1L/day associated with?
Secretory diarrhea
(Dehydration and electrolyte imbalance)
What are some common ingested osomoles that lead to osmotic diarrhea?
Antacids, sorbitol, olestra, lactulose
Common malabsorption causes?
Small intestinal mucosal diseases, intestinal resections, pancreatic insufficiency, lactase deficiency, lymphatic obstruction, reduced bile salts
Causes for reduced bile salts that help ingest fat and fat soluble vitamins?
Postcholecystectomy
Ileal resection or Crohn’s Dx
Small intestine bacterial overgrowth (SIBO)
Consequence of decreased bile salts?
Increase luminal osmoles (fat)
Increased colonic secretions
Secretory diarrhea?
Increased intestinal secretion (decreased absorption)
Lil’ change in stool output even when fasting
Common causes of secretory diarrhea?
Infection - travelers diarrhea
Hormonal : carcinoid (VIPoma, Zollinger-Ellison Syndrome) medullary thyroid carcinoma, adrenal insufficiency
Laxative Abuse
What are some routine tests to asses etiology of the diarrhea? Especially for chronic patients?
CBC, electrolytes, lover function, INR, ESR, C reactive protein, phosphorus, calcium, albumin, TSH, etc.
+ Celiac Dx serology
What does stool weight of <300g/day suggest?
Not actual diarrhea but a irritable bowel syndrome
What does a stool weight of >1000-1500g/24 hours suggest?
Secretory diarrhea
How do you calculate the osmotic gap for stool sample electrolyte levels?
290-2x(Na+K)
Small osmolar gap <50 = secretory diarrhea
What are some other things you can test in a stool sample?
Electrolytes, ova and parasites, fat (Sudan Stain), occult blood, leukocytes, or lactoferrin
If chronic secretory diarrhea suspected check for:
Serum - VIP (VIPoma), calcination (medullary thyroid carcinoma), gastrin (zollinger Ellison syndrome)
Urine - 5HIAA carcinoid metabolite
Imaging studies for chronic diarrhea?
Abdominal CT (pancreatic malfunction or neuroendocrine tumors)
Somatostatin receptor scintigraphy (neuroendocrine tumors)
Small intestine imagining
Diagnostic procedures you could do for chronic diarrhea?
Sigmoidoscopy or colonoscopy
(IBD or melanosis coli)
Upper endoscopy - celiac
Hydrogen breath test
Treatments for chornic diarrhea?
Loperamide, diphenoxylate w/ atropine, clonidine (secretory or diabetic), octreotide (secretory), Cholestyramine resin (bile salt)
