ABSTRACT
OBJECTIVE: To develop a system to score disease activity based on clinical manifestations in patients with active ulcerative colitis and to assess the relationship of this score with endoscopic disease severity as assessed by colonoscopy. METHODS: In a pilot study of 43 patients, nine clinical variables were examined by univariate analysis. Six factors that correlated with disease severity included age, well-being, defecation frequency, bloody stool, extraintestinal manifestations (Ext) and hemoglobin (Hb). Multivariate analysis resulted in the generation of a new activity index for the prediction of disease severity. Validation of this index was performed on 88 patients with definite diagnosis of ulcerative coli-tis based on previous histological examination. RESULTS: The activity index is derived as follows: (18 x bloody stool) + (20 x defecation frequency) + (5 x Ext) + (15 x Hb) - (well-being x 17) + (age x 2) + 158. Values below 280, between 280 and 310 and above 310 corresponded to mild, moderate and severe disease, respectively. The model classified disease severity correctly in 71% of cases. CONCLUSION: This activity index may be useful for noninvasive evaluation of disease severity in patients with ulcerative colitis.