J Korean Med Sci.  2002 Apr;17(2):168-172. 10.3346/jkms.2002.17.2.168.

Early Screening of Oxacillin-Resistant Staphylococcus aureus and Staphylococcus epidermidis from Blood Culture

• Jeong J
• Chang CL
• Park TS
• Lee SH
• Kim SR
• Jeong SH

• KMID: 648671
• DOI: http://doi.org/10.3346/jkms.2002.17.2.168

Abstract

The timely detection of blood-borne pathogens is one of the most important functions of the microbiology laboratory. Recently, methicillin-resistant staphylococci have become the most important pathogens seen by the laboratory. The purpose of this study was to evaluate Staphy agar, a novel screening medium, for the detection methicillin-resistant Staphylococcus aureus, S. epidermidis, or other coagulase-negative staphylococci (CNS) from positive blood cultures showing Gram-positive cocci in clusters. Eighty-six blood cultures that yielded Gram-positive cocci in clusters were included in this study. The organisms were finally identified by the Vitek system, and oxacillin resistance was confirmed by polymerase chain reaction (PCR)-based mecA gene detection. The identification and oxacillin resistance of all S. aureus strains showed complete agreement with the Vitek and PCR results. The presumptive detection of S. epidermidis and other CNS were consistent with the Vitek system in 94.7%, and the screening of oxacillin resistance was consistent with the result of PCR in 92.1% of 38 strains. The Staphy agar method is reliable and rapid for differentiating Gram-positive cocci in clusters in blood and for determining their methicillin resistance.

Keyword

Oxacillin; Staphylococcus aureus; Staphylococcus epidermidis

MeSH Terms

*Bacterial Proteins
Carrier Proteins/genetics
Drug Resistance, Microbial
*Hexosyltransferases
Muramoylpentapeptide Carboxypeptidase/genetics
Oxacillin/*pharmacology
Penicillin-Binding Proteins
*Peptidyl Transferases
Staphylococcus aureus/*drug effects/genetics
Staphylococcus epidermidis/*drug effects/genetics