CYTOKINE PRODUCTION IN POUCHITIS IS SIMILAR TO THAT IN ULCERATIVE-COLITIS

PURPOSE: Controversy exists as to whether pouchitis represents a react ivation of the immunologic mechanisms that lead to ulcerative colitis (UC). The aims of this study were to determine local levels of the cyt okines: interleukin-1 beta (IL-1 beta), interleukin-6 (IL-6), interleu kin-8 (IL-8), and tumor necrosis factor alpha (TNF alpha) in the mucos a of patients with ''asymptomatic'' ileoanal pouch (n = 25), pouchitis (n = 9), active UC (n = 20), normal ileum (n = 15), proctitis (n = 10 ), and normal colon (n = 15). METHODS: Lamina propria mononuclear cell s were isolated from mucosal biopsies by enzymatic dispersion and cult ured for 48 hours. Proinflammatory cytokine levels were measured in th e supernatants by enzyme-linked immunosorbent assay. RESULTS: IL-1 bet a, IL-6, IL-8, and TNF alpha secretions were significantly greater in pouchitis and active UC than in the noninflamed ileoanal pouch and nor mal controls (P < 0.001). There was significant correlation (r = 0.63, P < 0.05) between levels of cytokines expressed in pouchitis and acti ve UC. CONCLUSIONS: Increased cytokine expression occurs in both activ e UC and pouchitis and to a lesser extent in the long-standing ileoana l pouch.