Search

Objective: The aim of this study is to determine the species distribution, slime activity, and methicillin resistance of coagulase-negative staphylococci (CoNS) isolated from blood cultures as either contaminants or true bacteremia agents. Materials and Methods: In this study, 13.268 blood culture samples sent to our laboratory from various clinics during a two-year period were examined in terms of the presence of CoNS to clarify whether the isolates are true bacteremia agents, as defined by Centers for Disease Control and Prevention (CDC) criteria. The slime activities of true bacteremia agents (58 CoNS strains) and contaminants (50 randomly selected CoNS strains) were investigated by the Christensen method. The methicillin susceptibilities of the strains were determined by the disk diffusion method. Results: Although the frequency of slime production was 39.7% among the true bacteremia CoNS agents, it was 18% in CoNS that were judged to be contaminants (p<0.05). S. epidermidis was the most frequently isolated species for both the true bacteremia agent group (56.9%) and contaminant group (74%). Additionally, S. epidermidis was the bacterium most frequently characterized as slime producing in both groups. The methicillin resistance of slime-producing CoNS was determined to be 82.6% for the true bacteremia agent group and 77.8% for the contaminant group. Conclusion: The presence of slime activity in CoNS isolated from blood culture samples is supportive evidence that they are most likely the agents of true bacteremia cases. [ABSTRACT FROM AUTHOR]

The incidence of infections due to coagulase-negative staphylococci (CoNS) has been steadily increasing in recent years. In this report, we describe an isolate of the CoNS Staphylococcus lugdunensis from a wound specimen with a colony morphology distinct from that of a classical S. lugdunensis colony. Specifically, wrinkled, medium-sized, beta hemolytic, opaque, rough white colonies were detected on blood agar. Catalase-positive, coagulase-negative, gram-positive cocci-yielding such colonies should be suspected of being S. lugdunensis. [ABSTRACT FROM AUTHOR]