REFRACTORY POUCHITIS - DOES IT REFLECT UNDERLYING CROHNS-DISEASE

Typical 'pouchitis' is a well recognised complication of ileal pouches in ulcerative colitis. Infrequently, a refractory pouchitis (RP) pres ents with certain clinical, endoscopic, and pathological features rese mbling Crohn's disease and is often ascribed to misdiagnosis of the in itial colitis. To test that hypothesis and to identify risk factors fo r RP, this study reviewed cases of presumed ulcerative colitis with il eal pouches constructed at The Mount Sinai Hospital between 1973 and 1 986. Twenty four cases with RP (16 Kock pouches and eight pelvic pouch es) and 21 controls were compared for eight clinical variables. The or iginal colectomy slides from 15 RP and 18 control cases were reviewed blindly, classified into five histological categories (corresponding t o definite ulcerative colitis, definite Crohn's disease, and three ind eterminate groups), and scored for 23 histological features. There wer e no significant clinical differences between RP and control cases exc ept for more frequent extraintestinal manifestations (38% v 5%) and ma le preponderance (79% v 43%) in RP. There were also no significant dif ferences between the distributions of RP cases and controls among the five histological categories or in the 23 histological features studie d. Refractory pouchitis therefore does not seem to reflect underlying Crohn's disease, but may be linked to immunological mechanisms that ar e manifested clinically as extraintestinal complications.