Likely causes of secretory watery diarrhea
- Bacterial toxins
- Ileal bile acid malabsorption
- Inflammatory bowel disease (ulcerative colitis, Crohn’s disease, microscopic colitis [lymphocytic and collagenous colitis], diverticulitis)
- Vasculitis
- Drugs and poisons
- Stimulant laxative abuse
- Disordered motility or regulation (postvagotomy diarrhea, postsympathectomy diarrhea, diabetic autonomic neuropathy, amyloidosis, irritable bowel syndrome)
- Endocrine diarrhea (hyperthyroidism, Addison’s disease, gastrinoma, vasoactive intestinal polypeptide tumor [VIPoma], somatostatinoma, carcinoid syndrome, medullary carcinoma of the thyroid, mastocytosis)
- Other tumors (colon cancer, lymphoma, villous adenoma)
- Idiopathic secretory diarrhea (epidemic secretory [Brainerd’s] diarrhea, sporadic idiopathic secretory diarrhea)
- Congenital syndromes (e.g., congenital chloridorrhea)