Münevver KAYIN DİNÇ, Volkan ÖZENCİ, Sabire ŞÖHRET AYDEMİR

Kan kültüründe bakterilerin hızlı tanısı ve duyarlılıklarının saptanması

Amaç: Kan dolaşımı enfeksiyonu olan hastalarda; etkenin kısa sürede tanımlanması ve uygun antimikrobiyal tedavi uygulanması, morbidite ve mortalitenin azaltılması bakımından oldukça önemlidir. Bu çalışmada, kan kültüründen doğrudan tanımlama ve antibiyotik duyarlılık testlerinin yapılması için geliştirilen yeni bir yöntemin değerlendirilmesi amaçlanmıştır. Gereç ve Yöntem: BacT/Alert 3D sisteminde pozitif sinyal veren kan kültürü örneklerinden yıkama ve santrifüj işlemleri ile bakteriyel çökelti elde edildi. Bu çökeltiden Vitek MS kullanılarak tanımlama yapıldı, ardından VITEK 2 otomatize sisteminde doğrudan antibiyotik duyarlılık testi çalışıldı. Sonuçlar standart yöntem ile karşılaştırıldı. Bulgular: Tanımlama işlemi 80 kan kültürü örneğinde gerçekleştirildi. Doğrudan tanımlama işleminde 73 örnek tanımlandı ve bunlardan 72’si (%90) standart yöntemle uyumlu olarak sonuçlandı. Doğrudan antibiyotik duyarlılık testlerinin %97,9 oranında uyumlu olduğu saptandı. Değerlendirilen 635 antibiyotik duyarlılık sonucu içinde; 10’unda büyük hata, 3’ünde küçük hata olduğu görüldü. Sonuç: Kan kültürü örneklerinden çalışmada uygulanan prosedürler kullanılarak 24 saat içinde, maliyetli reaktifler ya da uzun işlem süresine gereksinim olmadan, standart uygulama sonuçlarına benzer bir şekilde tanımlama ve antibiyotik duyarlılık sonucu elde edilebileceği görülmüştür.

Rapid diagnosis of bacteria and determination of sensitivity in blood culture

Aim: In patients with bloodstream infection; identifying the causative agent in a short time and applying appropriate antimicrobial therapy is very important in terms of reducing morbidity and mortality. In this study, it was aimed to evaluate a new method developed for direct identification and antibiotic susceptibility testing from blood culture. Materials and Methods: Bacterial pellet was obtained from blood culture samples that showed positive signals in the BacT/Alert 3D system by washing and centrifugation. Identification was made from this pellet using Vitek MS, followed by direct antibiotic susceptibility testing in the VITEK 2 automated system. The results were compared with the standard method. Results: Identification was performed on 80 blood culture samples. In the direct identification process, 73 samples were identified, of which 72 (90%) resulted in agreement with the standard method. Direct antibiotic susceptibility tests were found to be compatible with a rate of 97.9%. Among the evaluated 635 antibiotic susceptibility results; it was observed that 10 of them had major errors and 3 of them had minor errors. Conclusions: Using the procedures applied in the study from blood culture samples, without the need for costly reagents or long processing time, it has been observed that identification and antibiotic susceptibility results can be obtained within 24 hours, similar to standard results.

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