Other microscopic colitis

This code represents microscopic colitis that does not fit the specific criteria for collagenous or lymphocytic colitis. It is characterized by chronic watery diarrhea, often with abdominal pain, and is diagnosed by microscopic examination of colonic biopsies showing inflammatory changes without macroscopic ulceration.

Use this code when documentation specifies "other microscopic colitis" or describes findings consistent with microscopic colitis that are not definitively collagenous or lymphocytic. Supporting documentation includes pathology reports detailing microscopic inflammatory changes in colonic biopsies and clinical notes describing chronic watery diarrhea.

• Ensure the pathology report explicitly rules out collagenous (K52.831) and lymphocytic (K52.832) colitis before assigning this code.
• Do not use this code for macroscopic colitis or inflammatory bowel disease (IBD) such as Crohn's disease or ulcerative colitis.
• Always review the full pathology report and clinical notes for the most specific diagnosis.