Investigation of the clinical features and recurrence patterns of acute right-sided colonic diverticulitis: A retrospective cohort study.

Background: Right-sided colonic diverticulitis (RCD) and left-sided colonic diverticulitis (LCD) are considered distinct diseases. However, separate guidelines for RCD do not exist. Since the establishment of RCD management would first require evaluation of disease characteristics and recurrence patterns, this study has aimed to investigate the differences in the clinical characteristics between RCD and LCD and the recurrence patterns of RCD. Methods: Patients admitted for colonic diverticulitis between January 2012 and August 2020 were retrospectively reviewed. Clinical characteristics and recurrence rates in RCD and LCD patients, and predictors for recurrence and the recurrence patterns of RCD were analyzed. Results: In total, 446 colonic diverticulitis patients (343 RCD, 103 LCD) were included in this study. RCD patients were more likely to be male, younger, taller, heavier, smoke, drink alcohol, have better physical performance scores, lower modified Hinchey stages and better initial laboratory findings. LCD patients were more likely to receive invasive treatments, have longer fasting and hospital days, higher mortality and cumulative recurrence rates (20.5% vs. 30.4%, P = 0.007). Recurrences in most RCD patients were of similar disease severity and received the same treatments for initial attacks, with rates of recurrence increasing after each recurrence. Predictors of the recurrence of RCD were complicated diverticulitis (hazard ratio[HR] 2.512, 95% confidence interval[CI] 0.127-5.599, p = 0.024) and percutaneous drainage (HR 6.549, 95% CI 1.535-27.930, p = 0.011). Conclusion: RCD is less severe and has a lower recurrence rate than LCD, suggesting that RCD should be treated conservatively. Patients with complicated diseases and those requiring percutaneous drainage are more likely to experience a disease recurrence, suggesting nonsurgical management may be insufficient.