Microscopic Colitis After Fecal Microbiota Transplant.

Microscopic colitis (MC) is an inflammatory condition of the large bowel that is associated with chronic, nonbloody diarrhea. Colonoscopy usually demonstrates normal mucosa, while tissue biopsy reveals intraepithelial lymphocytes or a subepithelial collagen band. Although no specific antibody has been discovered, MC is associated with several autoimmune disorders such as celiac disease, Hashimoto's thyroiditis, and rheumatoid arthritis. There are only a small number of case reports documenting possible hereditary MC cases, but up to 12% of patients with MC have a family history of inflammatory bowel disease. Other associations include proton pump inhibitor use, cigarette smoking, HLA-DQ2/86, and possibly some gastrointestinal infections.