Background and study aims: We studied the rate of pancreatitis and asymptomatic hyperamylasemia after endoscopic balloon dilation (EBD) and endoscopic sphincterotomy (EST) for removal of bile duct stones.
Patients and methods: Patients with bile duct stones of all sizes were randomly allocated to undergo EBD (8-mm dilation balloon) or EST. Pancreatitis was defined as epigastric pain combined with at least a threefold rise in serum amylase at 24 hours after the endoscopic retrograde cholangiopancreatography (ERCP). Asymptomatic hyperamylasemia was defined as a threefold rise in serum amylase without epigastric pain.
Results: There were 180 patients (67 men, 113 women; mean age 67, SD 16.2) available for analysis. Complete stone removal after a single ERCP was achieved in 82 (88%) of 93 EBD patients and in 81 (93%) of 87 EST patients (P = 0.38). Mechanical lithotripsy was used more frequently in the EBD group (31% vs. 13%, P = 0.005). Early complications occurred in 16 EBD patients (17%) and in 19 EST patients (22%) (P = 0.46). Pancreatitis was observed in seven patients in each group (8%). Logistic regression identified no significant predictors for the occurrence of pancreatitis. Asymptomatic hyperamylasemia occurred in 21 EBD patients (23%) vs seven EST patients (8%) (P = 0.008). Logistic regression identified EBD as the only significant predictor for asymptomatic hyperamylasemia: odds ratio 2.9 (95% confidence interval (CI) 1.1 to 7.3, R2 = 0.02).
Conclusions: We did not observe a difference in the rate of pancreatitis between EBD and EST. Asymptomatic hyperamylasemia was observed more frequently after EBD. Although asymptomatic hyperamylasemia is not a clinical entity, this finding may indicate that EBD causes more irritation of the pancreas than EST.