Background/aims: The aim of this study was to evaluate the characteristics of cryptogenic and biliary pyogenic liver abscess by comparing the clinical aspects between the two groups.
Methods: Of 119 patients treated for pyogenic liver abscess from 2000 to 2004, 82 subjects with cryptogenic liver abscess and 21 with biliary abscess were analysed retrospectively.
Results: There were no significant differences between the two groups regarding clinical symptoms. The characteristics of abscess were similar except the size of abscess. The size of abscess less than 5 cm in diameter was more common in biliary group than in cryptogenic group (p=0.004). Compare to cryptogenic group, biliary group had more positive culture test from abscess (100% vs. 69%, p=0.006). Especially, E. coli isolated from abscess culture (28% vs. 7%, p=0.014) and blood culture (23% vs. 4%, p=0.035) were more common in biliary group than in cryptogenic group. There was no difference in mortality between the two groups (biliary vs. cryptogenic: 4.8% vs. 0%, p=0.204). However, the rate of clinical improvement was higher in cryptogenic group than in biliary group (92.7% vs. 66.7%, p=0.001).
Conclusions: Biliary liver abscess had similar clinical characteristics to cryptogenic origin. Biliary liver abscess had smaller abscess size and more positive abscess culture rates than cryptogenic abscess. Improvement rate without complication and recurrence was higher in cryptogenic group than biliary group.