Impaired activation of the neutrophil oxidative metabolism in chronic inflammatory bowel disease.

The oxidative metabolism of circulating neutrophils was studied in patients with Crohn's disease and ulcerative colitis. The production of superoxide anion (02-.) in patients with ulcerative colitis was markedly decreased irrespective of whether soluble or particulate, non-chemotactic or chemotactic stimuli were used. Crohn's disease neutrophils showed a just marginally diminished 02-. production. Disease activity, as defined by the Crohn's disease activity index, was negatively correlated with the neutrophil O2-. production in both diseases. In both Crohn's disease and in ulcerative colitis neutrophil hydrogen peroxide (H2O2) production was normal. It is concluded that the neutrophil function, as-assessed by superoxide anion production, is impaired in patients with inflammatory bowel disease. It is therefore suggested that the suboptimal microbicidal function of these cells, as demonstrated in the present study, may contribute to the disease process.