Acute pancreatitis after removal of retained prophylactic pancreatic stents

Background: Prophylactic pancreatic stents (PPSs) are used to decrease the risk of post-ERCP pancreatitis (PEP) in high-risk patients. The risk associated with PPS removal is unknown.

Objective: To describe the rate of PEP in patients undergoing PPS removal without pancreatogram or other manipulation of the major or minor papilla.

Design: Retrospective, cohort study.

Setting: Tertiary care academic center.

Patients: This study involved 230 patients undergoing removal of PPSs from 1997 to 2010.

Intervention: PPS removal.

Main outcome measurements: Rate of acute pancreatitis associated with removal of PPS alone.

Results: Acute pancreatitis occurred after PPS removal in 7 of 230 (3.0%) cases. PEP was graded as mild, moderate, and severe in 2, 5, and 0 cases, respectively. Statistically significant risk factors of PEP after PPS removal include use of a 5F stent (P=.001), use of a stent with an internal flange (P<.01), and occurrence of PEP after the initial ERCP (P<.01). Longer duration of stent within the pancreatic duct before removal was of borderline significance (P=.06). Patient age; sex; indication for initial procedure; the presence of pancreas divisum, ansa loop, or chronic pancreatitis; and history of pancreatic or biliary sphincterotomy or orifice dilation were not significant risk factors for pancreatitis after PPS removal.

Limitations: Retrospective analysis of prospectively collected data. Small number of events.

Conclusion: Removal of retained PPSs may cause mild or moderate acute pancreatitis. This risk of acute pancreatitis may diminish the overall efficacy of PPS use by delaying the occurrence of PEP rather than eliminating it. This implies that PPSs should be used only in patients at high risk for PEP.