Isolated bacteria and susceptibilities to antimicrobial agents in biliary infections

A total of 209 bacterial strains were isolated from patients with biliary infection in our department between January 1982 and December 2000.

Antimicrobial susceptibility tests were conducted to ascertain the presence of drug-resistant bacteria.

The breakdown of the 109 strains from the patients with primary biliary infections was as follows: 70 strains of gram-negative aerobic bacteria; 27 strains of gram-positive aerobic bacteria; 6 strains of gram-negative anaerobic bacteria; and 6 strains of gram-positive anaerobic bacteria. Among the 100 strains isolated from the patients with postoperative infection, the frequency of anaerobic bacteria was similar, but the frequency of gram-negative aerobic bacteria was lower at 55 strains, whereas frequency of gram-positive aerobic bacteria was higher at 36 strains. Of the 70 strains of gram-negative aerobic bacteria isolated from patients with primary biliary infection, the following four bacteria accounted for 75% of the total: Klebsiella pneumoniae, Escherichia coli, Enterobacter spp., and Pseudomonas aeruginosa.

The frequencies of gram-negative aerobic bacteria were high among patients with primary biliary infection, while those of gram-positive aerobic bacteria were high among patients with postoperative biliary infection. Although VRE was not isolated, the frequency of MRSA was extremely high.