Bacteriology and prophylactic antibiotic study of biliary tract surgery

During a two-year prospective study [1980-1981], 186 bile specimens were cultured from patients who had undergone surgical operations of the biliary tract. The incidence of infected bile in the operated patients, 84/186 [45.2%], was higher in females, 65/136 [47.8%], than in males, 19/50 [38%]. Of the 84 infected bile cultures, 76 [90.4%] grew aerobic bacteria, and anaerobes were found in eight [9.6%] Septic complications developed in 11/108 [10.2%] of the patients. Prophylactic antibiotics proved useful in patients with infected bile cultures. This study confirms the importance of intraoperative bile cultures. Biliary tract infections are known to be caused by a wide variety of aerobic and anaerobic organisms[1-4]. Recently, polymicrobial biliary infections involving both aerobes and anaerobes had been frequently found in the presence of common duct stones[4-6]. It has been reported that operations on the biliary tract are associated with a 20-33% incidence of wound sepsis, and often occurred in cases with infected bile[2,6,7]. However, a few investigators demonstrated that patients with infected bile would benefit from preoperative prophylactic antibiotics[6,7]. This study describes the bacteriology of biliary tract infection and evaluates antibiotic prophylaxis in high risk patients undergoing biliary tract surgery