Multicentre study of non-surgical management of diverticulitis with abscess formation

Background: Treatment strategies for diverticulitis with abscess formation have shifted from (emergency) surgical treatment to non-surgical management (antibiotics with or without percutaneous drainage (PCD)). The aim was to assess outcomes of non-surgical treatment and to identify risk factors for adverse outcomes. Methods: Patients with a first episode of CT-diagnosed diverticular abscess (modified Hinchey Ib or II) between January 2008 and January 2015 were included retrospectively, if initially treated non-surgically. Baseline characteristics, short-term (within 30 days) and long-term treatment outcomes were recorded. Treatment failure was a composite outcome of complications (perforation, colonic obstruction and fistula formation), readmissions, persistent diverticulitis, emergency surgery, death, or need for PCD in the no-PCD group. Regression analyses were used to analyse risk factors for treatment failure, recurrences and surgery. Results: Overall, 447 patients from ten hospitals were included (Hinchey Ib 215; Hinchey II 232), with a median follow-up of 72 (i.q.r. 55–93) months. Most patients were treated without PCD (332 of 447, 74⋅3 per cent). Univariable analyses, stratified by Hinchey grade, showed no differences between no PCD and PCD in short-term treatment failure (Hinchey I: 22⋅3 versus 33 per cent, P = 0⋅359; Hinchey II: 25⋅9 versus 36 per cent, P = 0⋅149) or emergency surgery (Hinchey I: 5⋅1 versus 6 per c