Nevgün Sepin ÖZEN, Duygu DAĞLAR, Özhak Betil BAYSAN, Çiğdem YILDIRIM, HATİCE YAZISIZ, Dilara ÖĞÜNÇ, Gözde ÖNGÜT, DİLEK ÇOLAK, Meral GÜLTEKİN

Metisilin dirençli staphylococcus aureus suşlarının saptanmasında MRSA ID kromojenik besiyerinin değerlendirilmesi

Metisilin dirençli Staphylococcus aureus (MRSA) hem toplum hem de hastane kökenli infeksiyonlardan izole edilen önemli bir patojendir. S.aureus suşlarında metisilin direncinin doğru ve hızlı bir şekilde belirlenmesi, infeksiyon kontrol önlemlerinde ve hastanede yayılımın önlenmesi açısından anahtar rol oynamaktadır. Akdeniz Üniversitesi Merkez Laboratuvarı’na gönderilen klinik örneklerden izole edilen toplam 163 S.aureus suşunun tanımlanması Gram boyama, katalaz, lam ve tüp koagülaz yöntemleri ve BD Phoenix otomatize identifikasyon ve antimikrobiyal duyarlılık sistemi kullanılarak yapılmıştır. Suşlarda nuc ve mecA genlerinin varlığı ve 16S RNA, özgül primerler kullanılarak polimeraz zincir reaksiyonu (PZR) yöntemiyle saptanmıştır. S.aureus olarak tanımlanan tüm suşların MRSA ID kromojenik agar besiyerine ekimi yapılarak plaklar 35°C’de aerobik ortamda inkübe edilmiş ve sonuçlar koloni renklerine göre değerlendirilmiştir. Bu çalışmada MRSA ID besiyerinin performansının değerlendirilmesi amaçlanmıştır. MRSA saptanmasında, MRSA ID besiyerinin 24 saatlik inkübasyon sonrasında duyarlılığı % 85.4, özgüllüğü ise % 53.7 olarak bulunmuştur. Sonuç olarak MRSA ID, 18-24 saatlik inkübasyon sonucunda MRSA saptanmasında duyarlığının yüksek olması nedeniyle kullanılabilir bir besiyeridir.

Evaluation of MRSA ID chromogenic medium for detection of methicillin-resistant staphylococcus aureus

Methicillin-resistant Staphylococcus aureus (MRSA) is an important pathogen which is responsible for community -acquired and nosocomial infections. Rapid and accurate detection of methicillin resistance in S.aureus has become a key element on infection control measures and limiting the spread of this organism. In Akdeniz University Central Laboratory a total of 163 S.aureus strains which were isolated from various clinical specimens were identified by Gram staining, catalase test, slide coagulase test, tube coagulase test and BD Phoenix automated system. The presence of nuc and mecA genes and 16s RNA was detected using specific primers by PCR. The strains defined as S.aureus were inoculated on MRSA ID medium and incubated at 35°C aerobically. Results were evaluated according to colony colors. In this study we aimed to evaluate the performance of MRSA ID medium. The sensitivity and specificity of MRSA ID after 24 h incubation were found 85.4 % and 53.7 %, respectively. In summary, MRSA ID has been shown to be an applicable medium due to the high sensitivity for detection of MRSA after 18-24 h incubation.

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