Post-ERCP pancreatitis

Pancreatitis remains the most common severe complication of endoscopic retrograde cholangiopancreatography (ERCP). Detailed information about the findings of previous studies concerning post-ERCP pancreatitis has not been utilized sufficiently. The purpose of the present article was to present guidelines for the diagnostic criteria of post-ERCP pancreatitis, and its incidence, risk factors, and prophylactic procedures that are supported by evidence. To achieve this purpose, a critical examination was made of the articles on post-ERCP pancreatitis, based on the data obtained by research studies published up to 2009. At present, there are no standardized diagnostic criteria for post-ERCP pancreatitis. It is appropriate that post-ERCP pancreatitis is defined as acute pancreatitis that has developed following ERCP, and its diagnosis and severity assessment should be made according to the diagnostic criteria and severity assessment of the Japanese Ministry of Health, Labour and Welfare. The incidence of acute pancreatitis associated with diagnostic and therapeutic ERCP is 0.4–1.5 and 1.6–5.4%, respectively. Endoscopic papillary balloon dilation is associated with a high risk of acute pancreatitis compared with endoscopic sphincterotomy. It was made clear that important risk factors include dysfunction of the Oddi sphincter, being of the female sex, past history of post-ERCP pancreatitis, and performance of pancreaticography. Temporary prophylactic placement of pancreatic stents in the high-risk group is useful for the prevention of post-ERCP pancreatitis [odds ratio (OR) 3.2, 95% confidence interval (CI) 1.6–6.4, number needed to treat (NNT) 10]. Use of nonsteroidal anti-inflammatory drugs (NSAIDs) is associated with a reduction in the development of post-ERCP pancreatitis (OR 0.46, 95% CI 0.32–0.65). Single rectal administration of NSAIDs is useful for the prevention of post-ERCP pancreatitis [relative risk (RR) 0.36, 95% CI 0.22–0.60, NNT 15] and decreases the development of pancreatitis in both the low-risk group (RR 0.29, 95% CI 0.12–0.71) and the high-risk group (RR 0.40, 95% CI 0.23–0.72) of post-ERCP pancreatitis. As for somatostatin, a bolus injection may be most useful compared with short- or long-term infusion (OR 0.271, 95% CI 0.138–0.536, risk difference 8.2%, 95% CI 4.4–12.0%). The usefulness of gabexate mesilate was not apparent in any of the following conditions: acute pancreatitis (control 5.7 vs. 4.8% for gabexate mesilate), hyperamylasemia (40.6 vs. 36.9%), and abdominal pain (1.7 vs. 8.9%). Formulation of diagnostic criteria for post-ERCP pancreatitis is needed. Temporary prophylactic placement of pancreatic stents in the high-risk group offers the most promise as a means of preventing post-ERCP pancreatitis. As for pharmacological attempts, there are high expectations concerning NSAIDs because they are excellent in terms of cost-effectiveness, ease of use, and safety. There was no evidence of effective prophylaxis with the use of protease inhibitors, especially gabexate mesilate.