Lymphocytic colitis

This code identifies a chronic inflammatory condition of the colon characterized by an increased number of lymphocytes in the colonic epithelium, typically diagnosed via biopsy. Patients often present with chronic, watery, non-bloody diarrhea without significant endoscopic findings. It is a microscopic colitis, meaning the inflammation is only visible under a microscope.

Assign this code when documentation confirms a diagnosis of lymphocytic colitis, usually established through histological examination of colon biopsies. This diagnosis is often considered in patients experiencing persistent watery diarrhea with normal or near-normal colonoscopy results.

• Ensure the pathology report specifically states "lymphocytic colitis" to support this diagnosis.
• Distinguish from collagenous colitis (K52.831), another form of microscopic colitis, based on distinct histological features.
• Do not use for unspecified microscopic colitis; seek clarification if the specific type is not documented.