title: Risk factors for post-ERCP pancreatitis in high risk patients who have undergone prophylactic pancreatic duct stenting: a multicenter retrospective study.
abstract: OBJECTIVE
  Pancreatitis remains a serious complication after endoscopic retrograde cholangiopancreatography (ERCP). The efficacy of prophylactic pancreatic duct stent placement to prevent post-ERCP pancreatitis in patients at high risk has been established in several randomized controlled trials. The aim of this study was to investigate the frequency and risk factors of post-ERCP pancreatitis in patients who had undergone prophylactic pancreatic duct stenting.
  
  
  METHODS
  Between July 2002 and January 2010, ERCP-related procedures were performed in 9192 cases of pancreatobiliary diseases at seven institutions. Among them, 414 patients (246 men, 168 women; mean age, 68 yr; age range, 22-91 yr) at high risk of post-ERCP pancreatitis who had undergone prophylactic pancreatic duct stenting were included in this study. The stent used in the present study was a 5-Fr stent with a single duodenal pigtail, which is made of soft polyethylene and has no flange (Pit-stent: Cathex, Co., Ltd., Tokyo, Japan). The pancreatic duct stent was placed via the channel of the duodenoscope over a guidewire with the assistance of fluoroscopy at the end of the procedure. The frequency and risk factors of post-ERCP pancreatitis were investigated. Post-ERCP pancreatitis was defined based on the consensus criteria.
  
  
  RESULTS
  Therapeutic ERCP was performed in 52% of the patients. Indications for prophylactic pancreatic duct stenting were as follows: difficult cannulation of the bile duct, 192; pancreatic duct cytology/biopsy, 95; precut sphincterotomy, 40; pancreatic sphincterotomy, 29; female gender, 28; papillectomy, 25; sphincter of Oddi dysfunction, 12; history of pancreatitis, 10. Hyperamylasemia at 18-24 h after ERCP was observed in 64% (267 patients) of the patients. Pancreatitis occurred in 9.9% (41 patients: mild, 37; moderate, 2; severe, 2). Univariate analysis revealed intraductal papillary mucinous neoplasm (IPMN) of the pancreas to be the only significant risk factor for pancreatitis (OR 2.9, 95% CI 1.2, 7.1). Multivariate analysis also showed IPMN to be the only risk factor for pancreatitis (OR 3.1, 95% CI 1.2, 7.8). The mean diameter of the pancreatic head duct in patients with IPMN who developed post-ERCP pancreatitis was significantly smaller than that in those who did not develop pancreatitis (3.0 ± 1 mm vs 4.7 ± 2.6 mm, p=0.0037).
  
  
  CONCLUSIONS
  Post-ERCP pancreatitis developed in 9.9% of the patients at high risk who had undergone prophylactic pancreatic duct stenting. Since the majority of cases of post-ERCP pancreatitis were mild, pancreatic duct stenting may contribute to lessening the severity of pancreatitis. The present results suggest that IPMN without a dilated pancreatic head duct is a possible risk factor for post-ERCP pancreatitis after prophylactic pancreatic duct stenting.
authors.affiliation: Department of Gastroenterology, Sendai City Medical Center, Japan. keiito@openhp.or.jp
authors.forename: Kei
authors.initials: K
authors.lastname: Ito
authors.forename: Naotaka
authors.initials: N
authors.lastname: Fujita
authors.forename: Atsushi
authors.initials: A
authors.lastname: Kanno
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Matsubayashi
authors.forename: Shinji
authors.initials: S
authors.lastname: Okaniwa
authors.forename: Kazunari
authors.initials: K
authors.lastname: Nakahara
authors.forename: Kazuya
authors.initials: K
authors.lastname: Suzuki
authors.forename: Rhoichi
authors.initials: R
authors.lastname: Enohara
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002760:Cholangiopancreatography, Endoscopic Retrograde / Q000009:adverse effects*; D005260:Female; D006801:Humans; D034321:Hyperamylasemia / Q000209:etiology; D008297:Male; D008875:Middle Aged; D010183:Pancreatic Ducts / Q000601:surgery*; D010190:Pancreatic Neoplasms / Q000150:complications; D010195:Pancreatitis / Q000201:enzymology / Q000209:etiology* / Q000517:prevention & control; D012189:Retrospective Studies; D012307:Risk Factors; D015607:Stents / Q000009:adverse effects*; D013997:Time Factors; D055815:Young Adult