Causal bacteria of pyogenic liver abscess.

This is a review of bacteriologic data on 175 patients with pyogenic liver abscesses seen over a period of 8 years at Veterans General Hospital, Taipei, Taiwan. Positive cultures were obtained from liver aspirates in 151 of the 163 patients in which cultures were taken. One hundred and twenty patient specimens grew one isolate and 31 specimens grew two or more isolates. A total of 149 aerobic gram-negative rods, 25 aerobic cocci and 29 anaerobes were isolated. Ninety of the 159 patients from whom blood was taken had positive cultures. In 11 patients, two or more isolates were grown concurrently from the blood. A total of 87 aerobic gram-negative rods, 7 aerobic cocci and 10 anaerobes were isolated. Klebsiella pneumoniae was the most common microorganism, accounting for 50.8% of the cases. Other major pathogens were Escherichia coli (27.4%), anaerobes (15.4%), and viridans streptococci (6.2%).