Fully covered metal stents as a risk factor for acute cholecystitis in patients with biliary stricture: a multicenter retrospective study

Objective This study investigated the prevalence and risk factors for acute cholecystitis following the placement of fully covered self-expandable metal stents (FC-SEMS) during endoscopic retrograde cholangiopancreatography into the common bile duct (CBD), across patients with various indications. We aimed to evaluate whether FC-SEMS placement increases the risk of acute cholecystitis and to identify associated risk factors. Methods In this retrospective, multicenter study, 365 medical records from multiple hospitals were reviewed. All patients underwent FC-SEMS placement for biliary strictures. Demographic and clinical data, including complications, were collected. Logistic regression analysis was performed to assess associations between acute cholecystitis and variables such as gallbladder stones, CBD stones, CBD diameter, and stent length. Results Acute cholecystitis occurred in 8.8% of patients. On univariate analysis, the presence of gallbladder stones and smaller CBD diameter were significantly associated with increased risk of acute cholecystitis ( P = 0.01 and P = 0.02, respectively). Shorter stents (40–60 mm) were associated with a markedly higher incidence of acute cholecystitis (10.4%) compared to longer stents (70–100 mm) (1.5%; P = 0.02). Multivariate logistic regression revealed that gallbladder stones (odds ratio: 4.2; 95% confidence interval: 1.76–9.85; P = 0.001) and reduced CBD diameter (odds ratio: 0.88; 95% confidence interval: 0.79–0.98; P = 0.02) independently predicted acute cholecystitis among the subgroup of patients with 40–60 mm long stents. Patients who developed acute cholecystitis had significantly longer follow up durations (279.5 vs. 176.8 days; P < 0.05). Conclusion FC-SEMS placement, particularly with shorter stents, is associated with an increased risk of acute cholecystitis, especially in patients with gallbladder stones and narrower CBD diameters. These findings underscore the need for careful patient selection, individualized stent sizing, and extended follow up in high-risk populations.