Diarrhea

Consistency

Watery

• Infectious: Acute gastroenteritis

  • Acutely increased stool frequency/volume, vomiting, infectious exposure, dry mucous membranes, hyperactive bowel sounds

  • Fecal lactoferrin, stool culture, stool ova and parasites, C. difficile toxin

  • Oral rehydration, BRAT diet, loperamide (non-bloody), Pepto-Bismol (bloody), simethicone, lactobacillus, antibiotics

• Irritable bowel syndrome

  • Cramping abdominal pain with change in stool frequency/consistency for 2 to 3 months

  • CBC, TSH, CRP, ESR, FOBT, anti-tissue transglutaminase IgA, EGD

• Microscopic colitis: Elderly patients. Increased risk with > 6 months daily NSAID use. Confirm with colon biopsy.

• Laxative abuse

Fatty (malabsorption): Steatorrhea with gas +/- weight loss

• Giardiasis (included in acute gastroenteritis)

• Celiac disease

Inflammatory: Irritable Bowel Disease

• Crohn’s disease

• Ulcerative colitis

Additional Considerations

• GI: Constipation with overflow, colorectal malignancy

• Neurologic: Hyperthyroidism, serotonin syndrome

• Medication/Iatrogenic: Antacids, antibiotics, chemotherapy, pelvic radiation