Outcome of patients with acute sigmoid diverticulitis: multivariate analysis of risk factors for free perforation.

BACKGROUND: Sigmoid diverticulitis (SD) is common in the West; its incidence is increasing as the average age of the population increases. The aim of this study was to assess the clinical outcomes of patients with acute SD and to determine whether emergency operation was associated more often with previous episodes of acute diverticulitis.

METHODS: All consecutive patients admitted for acute SD were recruited prospectively over an 11-year period from January 1998 to December 2008. Multiple logistic regression was used to identify risk factors for free perforation.

RESULTS: We included 934 patients (490 men and 444 women; median age, 59.2 years): 450 (48.2%) presented for their first SD episode and 484 (51.8%) had a prior history of SD. Free perforation occurred in 152 patients: during the first episode of SD in 114 patients (25.3%), during the second in 29 (12.7%), during the third in 8 (5.9%), and during the fifth in 1 patient (0.9%; P < .001). No patient with >5 previous episodes of SD had free perforation. All 152 patients with free perforation required emergent operative intervention. After initial conservative therapy in 782 patients, 82 required early elective operative intervention owing to exacerbation of infection under antibiotic treatment. Late elective colectomy was performed in 299 patients during the inflammation-free interval, and operative intervention was recommended in 345 patients owing to complicated diverticulitis. Uncomplicated SD in 56 patients was managed conservatively. Comorbidity (>1 disorder) and the first episode of SD were identified as risk factors for free perforation on multiple logistic regression.

CONCLUSION: The risk of free perforation in acute SD decreases with the number of previous episodes of SD. The first episode thus is the most dangerous for a free perforation. The indication for colectomy should not be made based on the potential risk of free perforation.