dinitrochlorobenzene and depression of T-lymphocytes in Crohn's disease and ulcerative colitis

were measured in 15 patients with ulcerative colitis, 15 patients with Crohn's disease, and 12 normal control subjects. Diminished reactivity to DNCB was demonstrated in 87% of patients with Crohn's disease (p < 0 001) and in 53% with ulcerative colitis (p < 0 02), as compared with only 8-5 % of controls; anergy was more frequent in Crohn's disease than in ulcerative colitis (p < 0 05). Levels of circulating T-lymphocytes were also depressed in both Crohn's disease and ulcerative colitis (p < 0 001) as compared with controls, with the values lower in Crohn's disease than in ulcerative colitis (p < 0 02). There were no correlations ofDNCB response with extent, duration, or severity of disease nor with T-cell levels within any patient group. These data provide further support for the concept that there is impairment of cell-mediated immunity among many patients with chronic inflammatory bowel disease, including both Crohn's disease and ulcerative colitis.