Risk of colonic diverticular rebleeding according to endoscopic appearance

Background and study aims Re-commencement of bleeding (rebleeding) of colonic diverticula after endoscopic hemostasis is a clinical problem. This study aimed to examine whether endoscopic visibility of colonic diverticular bleeding affects the risk of rebleeding after endoscopic hemostasis. Patients and methods We performed a retrospective review of endoscopic images and medical charts of patients with colonic diverticular bleeding who underwent endoscopic hemostasis. Endoscopic visibility was classified into two types according to visibility of the source of bleeding; source invisibility due to bleeding or attached hematin (type 1), or endoscopically visible responsive vessels (type 2). Rebleeding rates within one year after initial hemostasis were examined. Results Of 93 patients with successful endoscopic hemostasis, 38 (41 %) showed type 1 visibility, while the remaining presented type 2. All patients received hemostasis with clipping, rebleeding developed in 20 patients (22 %). Type 1 visibility was more likely to be observed in patients with rebleeding (65 % vs. 34 %, P = 0.013). Multivariate analysis revealed that after endoscopic hemostasis, type 1 visibility (invisible source) was the only independent risk factor for colonic diverticular rebleeding (odds ratio, 3.05; 95 % confidence interval, 1.03 – 9.59, P = 0.044). Kaplan-Meier curve showed the cumulative incidence of rebleeding was significantly higher in patients with type 1 visibility than those with type 2 visibility (P = 0.0033, log-rank test) Conclusion Hemostasis by clipping for colonic diverticular bleeding without definite observation of the source of bleeding may not be sufficiently effective. Other hemostatic methods, including band ligation, should be considered when the source of bleeding is unclear.