CORRELATION BETWEEN ENDOSCOPIC SEVERITY AND THE CLINICAL ACTIVITY INDEX IN ULCERATIVE-COLITIS

Objective: The aim of this study was to examine the relationship betwe en a new activity index and the endoscopic severity assessed by sigmoi doscopy in patients with ulcerative colitis. Methods: We evaluated the sigmoidoscopic severity and Activity Index (AI) in 37 patients with d istal colitis, 23 with left-sided colitis, and 36 with total colitis, in which the severity was divided into three categories: grade 1 = mil dly active, grade 2 moderately active, and grade 3 = severely active. We examined the relationship between the AI or clinical parameters and the endoscopic severity in all 96 cases. Results: The AI was found to be significantly correlated with the degree of sigmoidoscopic activit y in all cases, as well as in those with distal colitis, left-sided co litis, or total colitis. When patients with both grade 1 sigmoidoscopi c activity and AI values of less than 150 were regarded to have mild c olitis and patients with either grade 2 or grade 3 sigmoidoscopic acti vity and AI values of more than 150 were regarded to have moderate or severe colitis, 10 of 37 (27%) in the distal colitis, one of 23 (4.3%) in the left-sided colitis, and four of 36 (11.1%) in the total coliti s groups were thus misclassified regarding the distinction between mil d colitis and moderate or severe colitis. Three of four patients with severity of grade 1, indicating AI values of more than 150, had total colitis, whereas the remaining one had left-sided colitis. On the othe r hand, 10 of 11 patients with severity of grades 2 or 3 with AI value s of less than 150 had distal colonic involvement. When the endoscopic activity was equivalent, the highest mean AI values occurred in total colitis whereas the lowest mean AI values were found in distal coliti s. Conclusions: The AI well reflects the sigmoidoscopic activity. High AI values with a low sigmoidoscopic severity are thus considered to r eflect extensive involvement, whereas a high sigmoidoscopic severity w ith low AI values is thought to indicate the involvement of the distal colon. (C) 1998 by Am. Coll. of Gastroenterology.