Anaerobic Pyogenic Liver Abscess

Abstract

The role of anaerobic bacteria in the etiology of pyogenic liver abscess has not been fully recognized. In 11 years we have encountered 25 cases of anaerobic liver abscess, which represent 45% of all liver abscesses seen in the same period. Blood cultures, usually reported as negative in this condition, were positive in 54% of our cases. Anaerobes recovered from abscess contents or blood in our patients included anaerobic or microaerophilic streptococci, Bacteroides, Fusobacterium, and Actinomyces. A literature survey disclosed an additional 165 cases of anaerobic liver abscess. Commonly described "sterile" abscesses undoubtedly reflect the lack of adequate anaerobic transport and culture techniques. Surgical drainage remains the cornerstone of treatment, but antimicrobial therapy is also important. Failure to recover existing anaerobic organisms may result in inappropriate drug therapy. In our series the mortality of diagnosed cases was 5% (1 fatality in 20 cases).