S261 The Incidence of Peripheral and Splanchnic Venous Thromboembolism in Acute Necrotizing Pancreatitis: A Systematic Review and Meta-Analysis

Introduction: Venous thromboembolism (VTE) is a well-established sequela of acute pancreatitis. No prior meta-analysis, however, has comprehensively explored the short-term incidence of peripheral and splanchnic VTE in patients with acute necrotizing pancreatitis (ANP). Methods: We performed a comprehensive literature search through May 23, 2025, to identify all studies reporting the incidence of extremity DVT (eDVT), pulmonary embolism, and various splanchnic (mesenteric, splenic and portal) venous thrombosis in adult patients with ANP. Two independent reviewers (VR and SP) screened articles and extracted relevant variables from each study. Statistical analysis was performed by AB using comprehensive meta-analysis (Biostat, CO, USA). The random-effects model and DerSimonian Laird method were used to calculate the pooled incidence and 95% confidence intervals (CI). The Higgins I2 index was used to assess heterogeneity, with I2 > 50% indicating significant heterogeneity. Results: Four studies reporting the incidence of eDVT/PE in 1,217 ANP patients, and thirteen studies reporting the incidence of SVT in 2,562 ANP patients during the in-hospital and early post-discharge period (up to 3 months post-discharge) were included in this study. The pooled incidence of eDVT was 14.5% (95% CI- 0.071-0.274, I2 = 94.266%) and the pooled incidence of pulmonary embolism was 6.1% (95% CI- 0.047-0.079, I2 = 14.742%). The pooled incidence of SVT was 36.2% (95% CI 0.272-0.462, I2 = 94.9%), with a subset of 6 studies with 1434 ANP patients reporting specific data on mesenteric vein, splenic vein, and portal vein thrombosis. The pooled incidence for these was 10.5% (95% CI 0.067-0.162, I2 = 82.4%), 20.6% (95% CI 0.115-0.343, I2 = 95.2%), and 12.4% (95% CI 0.092-0.165, I2 = 67.9%), respectively. Factors potentially contributing to the significant heterogeneity were explored. Conclusion: Current guidelines do not explicitly recommend prophylactic anticoagulation for admitted patients with ANP. However, given the high incidence of ANP-associated VTE in our study with persistent increased risk up to 3 months after discharge, further prospective large-scale studies with similar findings may start a discussion on the benefit/risk profile of in-hospital and/or post-discharge anticoagulation in this patient population, as in other pro-inflammatory conditions such as active inflammatory bowel disease (IBD).