Bacterial contamination of the biliary tree after choledochostomy.

Secondary exogenous contamination of bile after choledochostomy could be an important cause of long-term morbidity if infection persists after removal of the T tube. Surprisingly, documentation of the frequency of conversion of sterile to infected bile after choledochostomy has rarely been recorded. Patients undergoing exploration and T-tube drainage of the common bile duct between July 1966 and January 1975, in whom intraoperative and postoperative cultures of bile were available, were studied. Postoperative cultures were obtained from five to forty days after operation. Of ninety-five patients available for study, contamination developed postoperatively in previously sterile bile in 44 per cent. The common duct bile contained bacteria at operation in 42 per cent and remained sterile throughout in 14 per cent. The most common secondary contaminants were klebsiella group and Escherichia coli. The fate of the contaminating organisms in a biliary tree without anatomic abnormalities is unknown. Two cases are presented which suggest that persistent infection may linger in the biliary tree for many years and give rise to pigment calculi. Since bacterial cannot be eradicated so long as a foreign body remains in the common duct and because such bacteria may cause symptoms even in an anatomically normal biliary tree, we suggest that a closed system of biliary drainage be employed and that appropriate antibiotic therapy be instituted for seven to ten days after removal of the T tubes.