Çeşitli Klinik Örneklerden Izole Edilen Staphylococcus aureus Suşlarında Metisilin Direncinin Araştırılmasında Konvansiyonel PCR Yöntemi ile Sefoksitin Disk Difüzyon, Otomatize Sistem ve Chromogenic MRSA Agar Yöntemlerinin Karşılaştırılması

Abstract

Meticillin-resistant Staphylococcus aureus (MRSA) is one of the most important infectious agents. Therefore, fast and accurate diagnosis of MRSA is utmost important. Although mecA gene detection by PCR is reference method, conventional methods are preferred in routine practices due to simplicity. As conventional methods last 48-96 hours, several chromogenic media have been developed. Our objective was to compare the methods used for meticillin resistance detection with PCR. Forty-eight S. aureus strains isolated from various clinical specimens were included. Of the 48 S. aureus strains, 19 were mecA gene-positive and 29 were negative. mecA genepositive 19 strains were also meticillin-resistant by automated system and disk diffusion. On chromogenic agar, 15 of 19 MRSA strains were meticillin-resistant and 4 were meticillin-sensitive.Twentynine mecA gene-negative strains were susceptible to meticillin by automatized system and disk diffusion. Among 29 mecA gene-negative MSSA strains inoculated on chromogenic agar, 17 were methicillin-resistant. According to our study, chromogenic media would be ineffective to detected to meticillin-resistance because of low sensitivity and specificity in routine.