An elevation in the serum amylase concentration is common after endoscopic retrograde cholangiopancreatography (ERCP), occurring in up to 75 percent of patients; by comparison, acute clinical pancreatitis (defined as a clinical syndrome of abdominal pain and hyperamylasemia requiring hospitalization) is much less common . Nevertheless, acute pancreatitis is the most common serious complication of ERCP and is a common basis for malpractice claims related to ERCP [2-7].
This topic will review post-ERCP pancreatitis. Other aspects of ERCP are discussed separately. (See "Endoscopic retrograde cholangiopancreatography: Indications, patient preparation, and complications".)
Several proposed factors may act independently or in combination to induce post-ERCP pancreatitis. Two important factors are mechanical injury from instrumentation of the pancreatic duct and hydrostatic injury from contrast injection .
Prolonged manipulation around the papillary orifice, repeated instrumentation of the pancreatic duct, and multiple pancreatic duct injections are common when selective bile duct cannulation is difficult . This can result in mechanic injury to the duct or ampulla. Thermal injury from electrocautery current may produce edema of the pancreatic orifice, leading to obstruction of the pancreatic duct with impaired emptying of pancreatic secretions .
Hydrostatic injury from over-injection of the pancreatic duct is probably an important cause of pancreatitis after diagnostic ERCP and sphincter of Oddi manometry . Over-injection has probably occurred if gland acinarization is apparent during pancreatography (ie, visualization of the side branches of the pancreatic duct during contrast injection).