Low risk of complications in patients with first-time acute uncomplicated diverticulitis.

PURPOSE: First-time acute uncomplicated diverticulitis (AUD) has been considered to have an increased risk of complication, but the level of evidence is low. The aim of the present study was to evaluate the risk of complications in patients with first-time AUD and in patients with a history of diverticulitis.

METHODS: This paper is a population-based retrospective study at Västmanland's Hospital, Västerås, Sweden, where all patients were identified with a diagnosis of colonic diverticular disease ICD-10 K57.0-9 from January 2010 to December 2014. The records of all patients were surveyed and patients with a computed tomography (CT)-verified AUD were included. Complications defined as CT-verified abscess, perforation, colonic obstruction, fistula, or sepsis within 1 month from the diagnosis of AUD were registered.

RESULTS: Of 809 patients with AUD, 642 (79%) had first-time AUD and 167 (21%) had a previous history of AUD with no differences in demographic or clinical characteristics. In total, 16 (2%) patients developed a complication within 1 month irrespective of whether they had a previous history of diverticulitis (P = 0.345). In the binary logistic regression analysis, first-time diverticulitis was not associated with increased risk of complications (OR 1.58; CI 0.52-4.81). The rate of antibiotic therapy was about 7-10% during the time period and outpatient management increased from 7% in 2010 to 61% in 2014.

CONCLUSIONS: The risk for development of complications is low in AUD with no difference between patients with first-time or recurrent diverticulitis. This result strengthens existing evidence on the benign disease course of AUD.