Proposal of a new clinical index predictive of endoscopic severity in ulcerative colitis

Assessment of disease activity by clinical parameters in ulcerative colitis is still controversial. Different clinical indexes have been proposed. Colonoscopy provides detailed information on mucosal damage. The aim of this study was to identify, among 21 clinical and laboratory parameters, which were predictive of endoscopic activity. We included 137 consecutive patients with ulcerative colitis who underwent colonoscopy, clinical examination, and blood tests within 4 weeks. Endoscopic severity was recorded using a simple score (range, 0-30). The multiple stepwise regression coefficient of each significant variable predictive of mucosal damage was used to develop a new activity index predictive of endoscopic appearance (Endoscopic-Clinical Correlation Index; ECCI). We tested the ability of our score to discriminate patients with severe endoscopic disease, calculating the area under the receiver operator characteristic curve, and we compared it to activity indexes proposed by other authors. Endoscopic severity was significantly influenced by four parameters: bloody stool, nocturnal bowel movements, body temperature >37.5 degrees C, and serum albumin. The new scoring system was calculated as ECCI = {[serum albumin x (-26)] + (bloody stool x 17) + (nocturnal bowel movements x 16) + [fever (0 or 1) x 39]} + 107. The ECCI accurately identified patients with severe endoscopic disease in our sample (sensitivity = 81%, specificity = 95%). In conclusion, the ECCI should be useful in clinical practice because it is simple and strongly related to endoscopic activity.