Role of Ulinastatin in Preventing Post-Endoscopic Retrograde Cholangiopancreatography Pancreatitis: The Emperor's New Clothes or Aladdin's Magic Lamp?

Objectives: The role of prophylactic ulinastatin in the prevention of post-endoscopic retrograde cholangiopancreatography (ERCP) pancreatitis is debated. A meta-analysis of all published randomized clinical trials was performed to evaluate the efficacy of ulinastatin on post-ERCP pancreatitis. Methods: Searches were conducted in multiple databases composed of PubMed, EMBASE, the Cochrane Library, the Science Citation Index Expanded, and the China National Knowledge Infrastructure series full-text database. Primary outcome was post-ERCP pancreatitis, with or without hyperamylasemia. Results: Seven randomized clinical trials fulfilling the inclusion criteria were selected for meta-analysis, 5 comparing ulinastatin with placebo and 2 for ulinastatin versus gabexate. The incidence of post-ERCP pancreatitis was reduced by ulinastatin (odds ratio, 0.53; 95% confidence interval, 0.31-0.89; P = 0.02; test for heterogeneity: I2 = 0%; P = 0.51), so was the event of hyperamylasemia (odds ratio, 0.42; 95% confidence interval, 0.30-0.59; P < 0.00001; test for heterogeneity: I2 = 13%; P = 0.33). Subsequent sensitivity and subgroup analyses produced conflicting results. Conclusions: Ulinastatin shows to be of value on preventing post-ERCP pancreatitis and hyperamylasemia for patients in average risk, when given intravenously at a dose of not less than 150,000 U, just before ERCP. More high-quality trials are needed for further confirmation.