ETIOLOGIES OF DIARRHEA

Infectious

     Inflammatory pathogens (positive fecal leukocytes)

          E coli

               Enteroinvasive

          Salmonella

          Shigella

          Campylobacter

     Noninflammatory pathogens (negative fecal leukocytes)

          E coli

               Enterotoxigenic

               0157:H7

               Vibrio cholerae

               Giardia lamblia

               Entamoeba histolytica

               Cryptosporidium

               Norwalk virus

               Rotavirus

     HIV associated

          Cryptosporidium

          Microsporida

          Isospora belli

          Giardia lamblia

          Strongyloides stercoralis

          Entamoeba histolytica

          Mycobacterium avium-intracellulare

          Mycobacterium tuberculosis

          Cytomegalovirus

          Herpes simplex virus

          Epstein-Barr virus

Inflammatory (positive fecal leukocytes)

     Infections (see above)

     Inflammatory bowel disease

          Crohn’s disease (mucoid stools, right lower quadrant mass, diagnosed by endoscopy or enteroclysis)

          Ulcerative colits (hematochezia, diagnosed by colonoscopy or sigmoidoscopy)

          Collagenous colitis

          Microscopic (lymphocytic) colitis

     Ischemic colitis

     Radiation enteritis

     Niacin deficiency (Pellagra)

Osmotic (fecal osmotic gap >40 and symptoms decrease in response to fast)

     Lactose intolerance

     Fructose intolerance

     Sucrose intolerance

     Celiac disease

     Cystic fibrosis

     Malabsorption

          Fat (steatorrhea and fecal fat on sudan stain)

          Carbohydrate (stool pH <5.3)

     Laxatives

          Magnesium hydroxide

          Magnesium sulfate

          Lactulose

     Magnesium based antacids

     Artificial sweeteners

          Sorbitol

          Xylitol

     Bacterial overgrowth

     Chronic pancreatitis

     Short bowel syndrome

Secretory (fecal osmotic gap<40 and symptoms persist during fasting)

     Stimulant laxatives

          Phenolphthalein

          Senna

          Anthraquinones

          Ricinoleic acid

          Bisacodyl

     Toxins

          Heavy metals

          Organophosphates

          Ethanol

          Caffeine

          Bacterial

               Food poisoning

               Clostridium difficile

     Hormone producing tumors

          Gastrinoma

          Vipoma

          Mastocytosis

     Villous adenoma

Addison's Disease

Dysmotility

     Irritable bowel syndrome (IBS)

     Postvagotomy syndrome

     Diabetic autonomic neuropathy

     Thyrotoxicosis

     Carcinoid syndrome

     Hexosaminidase B deficiency

Postsurgical

     Ileal resections

     Cholecystectomy

     Right hemicolectomy

Medication side effect

     Antibiotics

     Antacids

     Antiarrhythmics

     Antihypertensives

     Antineoplastics

     Cholinergics

     Diuretics

     Quinidine

     Theophylline

     Metformin

     Colchicine

     Proton pump inhibitors

     Prokinetics

          Erythromycin

          Bethanechol

          Metoclopramide

 Laxatives

     Magnesium supplements

     Misoprostol

     Cholestyramine

     Neomycin

     Lactulose

     Para-aminosalicylic acid