Pancreatitis induced by endoscopic balloon sphincter dilation and changes in serum amylase levels after the procedure

The short-term safety of endoscopic balloon sphincter dilation remains to be defined. We prospectively investigated the rate of pancreatitis and changes in pancreatic enzyme values induced by endoscopic balloon sphincter dilation.

One hundred nine patients with bile duct stones were treated using endoscopic balloon sphincter dilation between July 1995 and September 1997. Serum amylase values were determined before and after the procedure in 100 patients treated 106 times, and these values were compared with the incidence of pancreatitis. Patients were classified into 3 categories according to serum amylase levels before therapy (group A, within the normal range; group B, above the normal upper limit up to 500 mU/mL; group C, above 500 mU/mL). The severity of pancreatitis was categorized into 4 grades (minimal, postprocedural abdominal pain lasting no longer than the next morning; mild, elevation of amylase values to at least three times normal accompanied by postprocedural abdominal pain necessitating treatment for 3 nights; moderate, required 4 to 10 nights of treatment; severe, required intensive care).

Postprocedural serum amylase levels in groups A and B were significantly elevated compared with baseline levels. In contrast, these levels in group C were decreased. Overall, postprocedural amylase levels were elevated in 95 studies. Minimal or mild pancreatitis developed in 21 (15 minimal and 6 mild) patients in groups A and B only.

Although pancreatic serum enzymes were elevated in almost all patients after endoscopic balloon sphincter dilation, procedure-related pancreatitis developed in a small percentage. There does not seem to be any contraindication to the use of endoscopic balloon sphincter dilation in patients with high amylase levels and an indication for the procedure, although such patients sometimes have stone-related pancreatitis or may be predisposed to developing pancreatitis.