Chemiluminescence in inflammatory bowel disease patients: a parameter of inflammatory activity

Background: Reactive oxygen species (ROS) are produced in excess in the inf lamed mucosa and peripheral blood of patients kith inflammatory bowel disea se. These species have emerged as a common pathway of tissue injury in a wi de variety of inflammatory and other disease processes. The present study w as conducted to assess ROS production and to correlate this with parameters of inflammatory activity. Methods: In 25 patients with Crohn's disease (CD ), 20 patients with ulcerative colitis (UC) and 65 age- and sex-matched hea lthy volunteers ROS production was measured using the whole blood luminol e nhanced chemiluminescence assay (LECA). Disease activity was assessed using the Crohn's disease activity index and the Ulcerative Colitis Symptoms Sco re (UCSS) for CD and UC, respectively. Furthermore, the effect of various s cavengers, enzymes and enzyme inhibitors on LECA was studied to assess the contribution of different ROS. Results: LECA was significantly higher in CD and UC patients compared with healthy controls (7.1 +/- 4.7 and 9.8 +/- 6 vs. 5.2 +/- 2.8 X 10(3) counts per minute (cpm), p < 0.05 and < 0.001). In CD, relative LECA (patient/control) was correlated with the Crohn's disease activity index and C-reactive protein (CRP) (r = 0.54, p = 0.001 and r = 0 .51, p = 0.01). In UC, CRP but rot LECA was correlated with the Ulcerative Colitis Symptoms Score (C-reactive protein: r = 0.42, p = 0.01). Addition o f azide, superoxide dismutase, deferoxamine and dimethylthiourea resulted i n a decrease of LECA values. Conclusion: Whole blood LECA is increased in p atients with CD and UC. This parameter is correlated with disease activity in CD. The observed chemiluminescence, is probably due to generation of sup eroxide and the hydroxyl radical. (C) 2001 Elsevier Science B.V. All rights reserved.