Endoscopic sphincterotomy-induced pancreatitis: increased risk associated with nondilated bile ducts and sphincter of Oddi dysfunction.

OBJECTIVE: to evaluate the relationship between common bile duct diameter and the risk of sphincterotomy-induced pancreatitis. METHODS: Two hundred and ten consecutive patients were prospectively investigated. Patients were divided into three groups according to the indication for sphincterotomy: Group I had common bile duct stones (n = 108), group II had sphincter of Oddi dysfunction (n = 48), and group III had sphincterotomy for other indications (n = 54) (i.e., stent, dilation). RESULTS: There were 62 males and 148 females with a mean age of 60 yr (range 15-93 yr). Eleven of the 210 patients (5.2%) developed pancreatitis. Other sphincterotomy-induced complications were bleeding (n = 2), cholangitis (n = 2), retroperitoneal duodenal perforation (n = 1), and bile duct leakage (n = 1). The percentages of pancreatitis in groups I (3.7%), II (12.5%), and III (1.9%) were significantly different (p = 0.03). Patients with nondilated common bile ducts (< or = 10 mm) had more pancreatitis than patients with dilated common bile ducts (8.8% vs. 2.8%), but the difference was not significant (p = 0.07). However, when group III was excluded from the analysis, there was a significant difference in the percentage of pancreatitis between the patients with nondilated bile ducts and those patients with dilated bile ducts (13.1% vs. 2.2%, respectively; p < 0.01). Analysis for trend did not show a significant inverse relationship between bile duct diameter and the rate of sphincterotomy-induced pancreatitis. However, for all complications combined, the inverse relationship between bile duct diameter and rate of sphincterotomy-induced complications was significant: < or = 5 mm (23.1%), > 5-10 mm (13.8%), > 10-15 mm (3.2%), > 15 mm (2.4%) (p = 0.002). CONCLUSIONS: Endoscopic sphincterotomy is more hazardous in patients with nondilated bile ducts and sphincter of Oddi dysfunction. Further studies are needed to determine whether pancreatic stenting reduces the risk of sphincterotomy-induced pancreatitis in those clinical settings.