Is pre-existing pancreatitis a risk factor for ERCP-induced pancreatitis?

There is limited data to support the conventional wisdom that patients with pre-existing pancreatitis are more susceptible to ERCP-induced pancreatic injury. The purpose of this prospective study was to determine the influence of antecedent pancreatic history on the risk of ERCP-induced pancreatitis. All patients undergoing ERCP were followed for development of complications. Diagnosis of ERCP-induced pancreatitis was based on previously published criteria (Gastrointest Endosc 1991;37:383). RESULTS: 39 of 787 patients (5.0%) developed pancreatitis after ERCP: 12 of 280 patients (4.3%) after diagnostic ERCP, 27 of 507 patients (5.3%) after therapeutic ERCP; p=≪0.001. 246 of 787 patients (31.2%) had a documented history of antecedent pancreatic injury. Etiologies of antecedent pancreatitis were: idiopathic (n=91), gallstones (n=50), alcoholic (n=35), ERCP (n=20), Sphincter of Oddi dysfunction (n=6), and other (n=44). ERCP-induced pancreatitis occurred in 6.1% of patients with a history of pancreatitis, and in 4.4% of patients without a history of pancreatitis; p=NS. Pancreatic History # of Patients ERCP-induced Pancreatitis (%) None 541 24(4.4) Acute < 6 wks 82 7(8.5) Acute> 6 wks 88 8(9.1) Chronic 76 0(0) TOTAL 787 39(5.0)*p=0.02, chi-square test Patients with a history of acute pancreatitis were more susceptible to pancreatic complications. In contrast, patients with chronic pancreatitis were relatively immune. CONCLUSION: Antecedent history of pancreatic disease is an important factor in predicting the risk of ERCP-induced pancreatitis.