Enzyme leakage, trypsinogen activation, and inflammatory response in endoscopic retrograde cholangiopancreatography-induced pancreatitis

Introduction: Endoscopic retrograde cholangiopancreatography (ERCP)-induced pancreatitis (EIP) provides an opportunity to study different pathophysiologic events early in the course of acute pancreatitis. Aims: To investigate whether the leakage of pancreatic proenzymes (anionic trypsinogen), pancreatic protease activation (carboxypeptidase B activation peptide), cytokine response (interleukin [IL]-1 receptor antagonist, IL-6, and soluble tumor necrosis factor receptor-I) and neutrophil activation (neutrophil gelatinase-associated lipocalin and polymorphonuclear elastase) differ between patients with and without EIP. A second aim was to clarify the temporal relation between these different events. Methodology: Ninety-nine nonconsecutive patients undergoing ERCP were investigated in the study. Results: Fourteen of 99 patients undergoing ERCP developed mild EIP. Six hours after the investigation the concentration of anionic trypsinogen was significantly higher in patients with EIP than in patients without EIP. The day after ERCP, higher concentrations of anionic trypsinogen, carboxypeptidase B activation peptide, IL-6, and polymorphonuclear elastase were recorded in the EIP group. No significant differences in IL-1 receptor antagonist. soluble tumor necrosis factor receptor-I or neutrophil gelatinase-associated lipocalin were found between the groups in this study. Conclusion: Mild EIP was accompanied by early leakage of proenzymes and later activation of trypsinogen/proteases. A significant cytokine response and neutrophil activation were recorded the day after ERCP. but further studies are needed to determine the temporal relation between these different pathophysiologic events.