Ceren KARAHAN, Alper TEKELİ, İştar DOLAPÇI, Özay Arıkan AKAN, Esra KOYUNCU

İnvaziv ve invaziv olmayan örneklerden izole edilen Candida albicans suşlarının genotip dağılımı

Amaç: Bu çalışmada, sepsisli hastaların kanından izole edilen invaziv C. albicans izolatları ile, sağlıklı ve Human-Immunodefi ciency Virus (HIV) ile infekte kişilerin boğazlarından izole edilen invaziv olmayan C. albicans izolatlarının genotip dağılımlarının belirlenmesi ve aynı bölgeyi hedef alan iki ayrı primer çifti kullanılarak elde edilen sonuçların karşılaştırılması amaçlanmıştır. Gereç ve Yöntem: Çalışmaya, kandan izole edilen 42 adet C. albicans suşu (invaziv izolatlar) ile HIV pozitif hastaların boğaz çalkantı sularından elde edilen 38, sağlıklı erişkinlerin boğaz çalkantı sularından izole edilen 30 adet C. albicans suşu (invaziv olmayan izolatlar) dahil edilmiştir. C. albicans identifi kasyonu konvansiyonel mikrobiyolojik yöntemlerle gerçekleştirilmiş ve polimeraz zincir reaksiyonu (PZR) yöntemi ile doğrulanmıştır. 25S intron genotiplendirmesi, CaLSU-F ve CaLSU-R ile CA-INT-L ve CA-INT-R primerleri kullanılarak gerçekleştirilmiştir. Bulgular: Kandan izole edilen 42 adet C. albicans suşunun 12’si genotip A (%28.5), 17’si genotip B (%40.5) ve 13’ü genotip C (%31) olarak bulunurken, sağlıklı kontrollerden izole edilen 30 adet C. albicans suşunun 9’unun genotip A (% 30), 12’sinin genotip B (% 40) ve 9’unun genotip C (%30) dağılımında olduğu gösterilmiştir. HIV pozitif bireylerden elde edilen 38 adet C. albicans suşunun 15’i genotip A (%39.5), 7’si genotip B (%18.4) ve 16’sı genotip C (%42.1) olarak bulunmuştur. Her iki primer ile de elde edilen sonuçlar birbirleriyle uyumlu bulunmuştur. Sonuç: İnvaziv ve non-invaziv örneklerin genotip dağılımları birbirleriyle karşılaştırıldıklarında istatistiksel olarak anlamlı bir fark görülmemiştir.

Genotype distribution of Candida albicans strains isolated from invasive and noninvasive samples

Aim: The aim of this study was to genotype C. albicans strains isolated from blood cultures of sepsis patients (invasive isolates) and from oral rinse samples of healthy adults and HIV-positive patients (non-invasive isolates) by using two diff erent primer sets targeting the same gene. Materials and Methods: 42 C. albicans invasive isolates obtained from sepsis patients and 68 oral non-invasive isolates obtained from oral rinse samples of healthy adults (n=30) and HIV-positive patients (n=38) were included in this study. C. albicans identifi cation was made by conventional microbiological tests and confi rmed by polymerase chain reaction (PCR). 25S intron genotyping was performed by using CaLSU-F and CaLSU-R primers and by using CA-INT-L and CA-INT-R primers. Results: Twelve of the 42 C. albicans isolates from blood samples were genotype A (28.5%), 17 were genotype B (40.5) and 13 were genotype C (31%). In the noninvasive group, genotype distribution of the HIV-positive patients and healthy controls were as follows: 15 (39.5%) of the 38 oral isolates obtained from HIV-positive patients were found as genotype A, 7 (18.4) genotype B, and 16 (42.1%) genotype C. Among the 30 oral isolates obtained from healthy adults, 9 (30%) were genotype A, 12 (40%) were genotype B, and 9 (30%) were genotype C. The results obtained by using both of the primers were in correlation with each other. Conclusion: No statistical signifi cant diff erence was observed between the genotype distributions of invasive and noninvasive isolates.

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