Microbiology of liver abscesses and the predictive value of abscess gram stain and associated blood cultures

Although rare, pyogenic liver abscesses are potentially fatal. We evaluated the predictive value of Gram stain of liver abscess aspirates and temporally associated blood cultures. Grain stains detected bacteria in 79% of the liver abscesses tested. The sensitivity and specificity of Grain stain of the liver abscesses were 90% and 100% for Gram-positive cocci (GPC) and 52% and 94% for Gram-negative bacilli (GNB). The sensitivities of the blood cultures for tiny GPC and GNB present in the liver abscess were 30% and 39%, respectively. Although. Grain stains and blood Cultures offer incomplete detection of the microbial contents of pyogenic liver abscesses, both tests should always accompany liver abscess cultures. (C) 2003 Elsevier Inc. All rights reserved.