Does bile of patients with acute gallstone pancreatitis cause pancreatic inflammatory lesions? A study of the pancreatic toxicity of choledochal secretions collected at ERCP.

BACKGROUND

Bile flow into the pancreatic duct has been proposed as the cause of acute biliary pancreatitis. However, the pancreatic toxicity of choledochal bile from patients with acute gallstone pancreatitis has not been studied.

METHODS

Bile was collected endoscopically from the common bile ducts of 21 patients with acute gallstone pancreatitis within 72 hours after the onset of disease. The bile samples were instilled into the pancreatic duct of rabbits, and light microscopic examination of the pancreas morphology was performed to assess the toxicity of human bile. Microbiologic quantitative analysis of the aerobic and anaerobic bacterial bile flora was performed.

RESULTS

Bile of six patients with acute gallstone pancreatitis (29%) induced interstitial inflammation in the rabbit pancreas. Choledochal bile of these patients harbored more than 10(4) CFU/mL bacteria (Proteus vulgaris, n = 1; Klebsiella pneumoniae, n = 1; Escherichia coli, n = 2; enterococci, n = 2). After sterilization, the bile samples did not induce acute pancreatitis. In 15 patients (71%), bile did not cause acute pancreatitis in the rabbit pancreas. These choledochal secretions were sterile or contained less than 10(4) CFU/mL.

CONCLUSIONS

Reflux of infected bile may be a potential cause of acute pancreatitis in the minority of patients with bacterobilia. In most patients with gallstone pancreatitis, bile is neither infected nor harmful to the pancreas, and its flow into the gland is unlikely to be the cause of inflammation.