Mucin secretion in inflammatory bowel disease: correlation with disease activity and dysplasia.

When rectal biopsies from 65 patients with ulcerative colitis and 20 patients with Crohn's disease was stained for mucins, an abnormal pattern (excess of sialomucins) was seen in about half of them. This is in contrast with 65 cases of non-specific proctitis where the mucin pattern of rectal biopsies was normal in all except one case. The abnormal mucin secretion in patients with ulcerative colitis was apparently related to the activity, duration, and extent of the disease. All biopsies with dysplasia showed predominant sialomucin staining except one. All biopsies showing sialomucins during remission also had dysplasia, while during active disease a number of biopsies had increased sialomucins without the evidence of dysplasia. It is not known if such cases will subsequently develop morphological atypia.