Abstract:Objective:To study the clinical characteristics, and the diagnosis and treatment of single and multiple pyogenic liver abscess. Methods:In past 25 years, 148 pyogenic liver abscess patients treated in our hospital were divided into single and multiple abscess groups. Clinical features, methods of treatment, and outcome were assessed and compared in the 2 groups. Results:A biliary origin was most frequently found in multiple abscesses than that in with single abscess(P=0.018). Mean age, duration of symptoms and length of hospital stay were higher in patients with multiple abscesses (P=0.023, 0.043， 0.015). High levels of alkaline phosphatase and low levels of albumin were more frequently seen in cases of multiple abscesses than in those of single ones(P=0.021 and 0.039). The lesions were most frequently located on the right lobe in single abscess group (P=0.002); and in the multiple abscess group, the two lobes were usually involved (P<0.001). E.coli was the most frequently cultured organism in either the single or multiple abscess groups. Antibiotic therapy alone was most frequently used in multiple abscess group (P=0.022), and percutaneous aspiration or catheter drainage usually used in single group (P=0.021). ARDS was most frequently seen in the multiple abscesses group (P=0.03). The morality rate was higher in multiple abscess group(P=0.025). Conclusions:Compared with single abscess group, multiple abscess group had the following features:the patient was older, duration of symptoms was longer, co-existing biliary diseases, invasion of two lobes, prone to develop ARDS and higher morality rate. Operation and/or simple antibiotic therapy are important therapies for multiple abscesses.