Introduction
Pyogenic liver abscesses are considered to be a rare, but life-threatening disease of the liver with a worldwide incidence of 2.3 to 17.6 cases per 100,000.[1] For the past few years, however, the incidence has been increasing. Pyogenic liver abscesses now represent 50% of all abscesses in the abdominal cavity.[2] The mortality of pyogenic liver abscesses has been reported in the literature at 11-31%.[3, 4] Whilst the major causes of pyogenic liver abscesses were once ascribed to intra-abdominal infections (e.g. appendicitis) or trauma of the hepatobiliary system, more than 55% of cases are now associated with an unknown cause of the disease.[3] The predominant bacterial spectrum includes Escherichia coli , Streptococcus spp., and anaerobes. [4] In recent times, however,Klebsiella pneumoniae is increasingly being found in abscess biopsy samples, particularly in Asia.[5, 6] Affected patients often present with co-morbidities or risk factors, such as diabetes mellitus.[7, 8] Treatment generally involves in-patient admission, using a combination of antibiotic treatment and percutaneous drainage.[9-11] Current guidelines recommend intravenous antibiotic treatment for up to three weeks, followed by oral antibiotics for 1-2 months.[8, 12, 13] The diameter of the inflammatory liver lesion has significance for both the prognosis and the choice of treatment. Liver abscesses with a diameter of up to 5 cm can be treated conservatively using antibiotics alone with a very good prognosis; larger abscesses, by contrast, should be additionally treated using percutaneous drainage or surgery. Mortality increases with increasing size of the abscess, and with decreasing Hb values.[14, 15]