Perianal Crohn disease: a new scoring system to evaluate and predict outcome of surgical intervention

BACKGROUND: Conventional Crohn disease activity indices do not reflect perianal disease activity or allow prognostic implications from surgery. HYPOTHESIS: A new scoring system, based on the patient's disease history and physical examination findings, will allow more accurate use of surgical intervention for perianal Crohn disease. METHODS: A standardized scoring questionnaire was developed and applied to a consecutive group of patients before surgical treatment of perianal Crohn disease. The scoring system included abscess, fistula, ulcer and fissure, stenosis, incontinence, and concomitant disease. Weighted factors included acuity vs chronicity, de novo vs recurrent disease, and concomitant intestinal disease. The scoring system was validated against the surgical outcome, which was classified as poor, satisfactory, or good. RESULTS: Twenty-eight patients with Crohn disease who underwent 33 surgical procedures had a mean score of 16.5 (range, 3-37; possible range, 0-55). Using the Spearman nonparametric correlation test, the scoring system was accurate in predicting the outcome of surgical intervention (correlation coefficient, 0.78, 95% confidence interval, 0.57-0.89; P<.001) at mean follow-up of 20.8 months (range, 6-40 months). Correlation was further validated using a linear regression model (r = 0.75, slope best-fit value, 3.8; 95% confidence interval, 2.46-5.14; P<.001). All patients with a score of 10 or less had a good outcome, whereas all those with a score of 20 or greater had a poor outcome. CONCLUSIONS: The proposed scoring system correlated well with the short-term outcome of surgical intervention in patients with perianal Crohn disease and allowed prediction of surgical success. Ultimately, it may be possible to alter therapy based on preoperative prediction of the expected postoperative outcome.