Comparison of pyogenic liver abscesses of biliary and cryptogenic origin. An eight-year analysis in a University Hospital.

OBJECTIVES: The aim of this study is to delineate the clinical features of pyogenic liver abscesses of biliary and cryptogenic origin, and to compare the differences in outcome of patients between the two groups.
METHODS: We studied 86 patients, aged 19 years or older, with pyogenic liver abscess admitted to Chung Shan Medical University Hospital, Taichung, Taiwan, between January 1996 and December 2003. The demographic data and medical information of the patients were reviewed and recorded. Of the 86 patients, 34 were classified into the biliary group and 52 were classified into the cryptogenic group.
RESULTS: Patients with pyogenic liver abscesses of biliary origin had a higher frequency of underlying malignancy and Murphy's sign compared to those with pyogenic liver abscesses of cryptogenic origin. With respect to specific pathogens, Escherichia coli were more prevalent in the biliary group while Klebsiella pneumoniae were more prevalent in the cryptogenic group. Anaerobic isolates were less frequently cultured in the cryptogenic group than in the biliary group. After adjustment for age, sex, and the duration of symptoms before admission, there was no difference in mortality between both groups (biliary vs cryptogenic: 15% vs 8%; adjusted OR, 1.43; 95% CI, 0.24-8.25; p = 0.899). After adjustment for confounders, patients in the biliary group had higher frequencies of time to defervesce >1 week after admission (68% vs 40%; adjusted OR, 3.05; 95% CI, 1.09-9.04, p = 0.030) and hospital stay >3 weeks (47% vs 15%; adjusted OR, 4.34; 95% CI, 1.45-13.91; p = 0.007) than those in the cryptogenic group.
CONCLUSIONS: This report highlights that pyogenic liver abscesses of cryptogenic origin had a benign clinical response, which was associated with shorter duration of hospitalisation and time to defervesce after admission, compared to those of biliary origin.