ERCP in Idiopathic Recurrent Acute Pancreatitis

The therapeutic impact of ERCP with sphincterotomy in the management of patients with idiopathic recurrent acute pancreatitis (RAP) needs further study. The investigators conducted a single center, feasibility, randomized trial to determine 1) the role of pancreatic manometry in predicting future episodes of RAP and 2) differences in the efficacy of no, biliary (BES) or pancreatobiliary (dual) endoscopic sphincterotomy (DES).

Patients with idiopathic RAP, defined as ≥2 unexplained (per the treating physician) episodes of acute pancreatitis (based on standard criteria) requiring hospitalization, will be prospectively enrolled. All patients will undergo ERCP with manometry, with stratified randomization based on the assessment of pancreatic basal sphincter pressure. If <40mmHg, the patient will be randomized to sham or biliary sphincterotomy (BES). If ≥40mmHg, the patient will be randomized to BES or pancreatobiliary ("dual") sphincterotomy (DES). Patients and physicians will not be blinded to the assignment group. Patients will be followed for up to 10 years to determine 1) incidence of RAP requiring hospitalization (using standard definitions) or 2) interval development of chronic pancreatitis (CP). Differences between patients who did and did not develop RAP during follow-up will be compared to evaluate for factors associated with AP during follow-up.

Among patients with normal sphincter of Oddi manometry, patients will undergo no sphincterotomy (sham therapy).

Patients will be followed post-ERCP for up to 10 years. The primary outcome is development of acute pancreatitis following the index ERCP, based on standard definitions. Acute pancreatitis is defined as new onset of pancreatic-type abdominal pain with associated elevation in serum amylase or lipase > 3 times the upper limit of normal, OR radiographic findings consistent with acute pancreatitis.

Determine the incidence of chronic pancreatitis during prolonged follow-up. Chronic pancreatitis is defined as characteristic changes on cross sectional imaging (CT or MRI/MRCP) or ERP (Cambridge classification).

A post hoc analysis will be conducted to evaluate for independent factors associated with having recurrent acute pancreatitis during follow-up

Inclusion Criteria: Idiopathic recurrent acute pancreatitis, defined as two or more episodes requiring hospitalization ERCP with SOM planned Exclusion Criteria: Chronic pancreatitis Pancreas divisum Alternate etiology identified (e.g., CBD stone, IPMN) Inability to perform pancreatic manometry Pregnancy, age < 18, incarceration Inability to provide informed consent

Cote GA, Imperiale TF, Schmidt SE, Fogel E, Lehman G, McHenry L, Watkins J, Sherman S. Similar efficacies of biliary, with or without pancreatic, sphincterotomy in treatment of idiopathic recurrent acute pancreatitis. Gastroenterology. 2012 Dec;143(6):1502-1509.e1. doi: 10.1053/j.gastro.2012.09.006. Epub 2012 Sep 11.