Right-sided colonic diverticulitis in a non-Asian population: A 12-year study of recurrence patterns and predictive factors

Abstract

Right-sided colonic diverticulitis (RCD) is common in Asian countries but remains uncommon in Western and African populations. Data on its natural history and recurrence in non-Asian settings are scarce. This study aimed to identify predictive factors for recurrence of RCD in a Tunisian cohort. A retrospective study was conducted including all patients admitted with a first episode of RCD between January 2012 and December 2024. Only patients managed non-operatively were included; all were treated conservatively with antibiotics ± percutaneous drainage. This 12-year inclusion period reflects the low regional incidence of right-sided diverticulitis and the progressive expansion of our referral catchment and CT imaging availability after 2016, which improved diagnostic yield. Recurrence was defined as a new CT-confirmed episode occurring ≥ 30 days after complete resolution of the index event. Recurrence-free survival was analyzed using the Kaplan–Meier method, and predictors of recurrence were determined by Cox proportional hazards regression. Secondary aims included evaluating the time to recurrence and characterizing the severity of recurrent episodes. Among 102 patients identified with right-sided colonic diverticulitis between 2012 and 2024, eighty-two patients were included (mean age 56.4 ± 14.2 years; 58.5% men). Diverticula were located in the cecum (54%), ascending colon (37%), or hepatic flexure (9%). The initial episode was managed conservatively in all cases; three patients (4%) required percutaneous drainage. During a median follow-up of 30 months, 15 patients (23.2%) experienced recurrence, with a mean interval of 11.2 ± 5.8 months. Most recurrences were mild and treated nonoperatively. Factors independently associated with recurrence were age > 60 years (HR = 2.8, 95% CI 1.1–7.2, p = 0.002), presence of comorbidities (HR = 3.5, 95% CI 1.3–9.4, p = 0.034), and initial disease severity (Hinchey Ib–II) (HR = 4.1, 95% CI 1.6–10.5, p = 0.001). Neither diverticular location nor antibiotic regimen influenced recurrence. Recurrence after RCD is not limited to Asian populations. In this first Tunisian study, one in four patients experienced recurrence, mostly within the first year. Advanced age, comorbidities, and severe initial disease were factors associated with recurrence. These findings suggest the need for tailored follow-up strategies in non-Asian populations.