Prognostic value of rectal biopsies in idiopathic ulcerative colitis.

Eighty seven biopsies and five total colectomy specimens following surgery were studied in 40 cases with idiopathic ulcerative colitis. They were categorised as acute ulcerative colitis with evidence of chronic activity in the first or subsequent biopsies (10 cases), chronic active ulcerative colitis (25 cases), and chronic quiescent ulcerative colitis (5 cases). The histological criteria were predefined with special reference to chronic crypt changes. Repeat biopsies were available in 28 cases and were found to be valuable in diagnosis and follow up of the disease.