Hastane enfeksiyonu etkeni klebsiella pneumoniae izolatlarında çeşitli virülans faktörlerinin araştırılması
Yükleniyor...
Dosyalar
Tarih
2017
Dergi Başlığı
Dergi ISSN
Cilt Başlığı
Yayıncı
Erişim Hakkı
info:eu-repo/semantics/openAccess
Özet
Klebsiella pneumoniae genellikle immünsupresif hastaları etkileyen ve hastane kaynaklı enfeksiyonlara neden olan fırsatçı bir patojendir. K.pneumoniae özellikle kapsül polisakkaridi, hipermukoviskozite (HV), fimbria, toksinler ve demir alım determinantları gibi pek çok virülans faktörüne sahiptir. Bu çalışmanın amacı, iki yıl içerisinde hastane kaynaklı enfeksiyonlardan izole edilen K.pneumoniae izolatlarında çeşitli virülans faktörlerini araştırmaktır. Selçuk Üniversitesi Tıp Fakültesi Hastanesi Tıbbi Mikrobiyoloji Laboratuvarında 2011-2013 yılları arasında çeşitli kliniklerde hastane enfeksiyonu tanısı almış hastalara ait örneklerden izole edilen 53 adet K.pneumoniae izolatı çalışmaya alınmıştır. İzolatların tanımlama ve antimikrobiyal duyarlılık testleri VITEK 2 otomatik sistemi (bioMerieux, Almanya) ile yapılmıştır. Biyofilm oluşturma yetenekleri, alfa hemolizin üretimi, kapsül ve hipermukoviskozite özellikleri fenotipik yöntemlerle araştırılmıştır. Adezin kodlayan virülans genleri (fimH-1, mrkD, kpn, ycfM), siderofor genleri (entB: enterobactin, iutA: aerobactin, irp-1, irp-2, ybtS, fyuA: yersiniabactin, iroN: catechols receptor) protektin veya invazin (rmpA, magA, traT) ve toksin (hlyA, cnf-1) virülans genlerinin varlığı polimeraz zincir reaksiyonu (PCR) ile araştırılmıştır. Toplam 53 K.pneumoniae izolatının 12 (%22.6)'si reanimasyon yoğun bakım ünitesi, 8 (%15.1)'i tıbbi onkoloji servisi, 7 (%13.2)'si yenidoğan yoğun bakım ünitesi ve 26 (%49)'sı diğer servislerde yatan hastalardan izole edilmiştir. Örneklere göre izolatların dağılımı şu şekildedir: 14 (%26.4)'ü idrar, 13 (%24.5)'ü kan, 10 (%18.9)'u drenaj sıvısı, 8 (%15.1)'i yara, 7 (%13.2)'si bronkoalveoler lavaj ve 1 (%19)'i beyin omurilik sıvısından üretilmiştir. İzolatların %5.7'si meropeneme dirençli, %71.7'si genişlemiş spektrumlu beta-laktamaz üretimi pozitif olarak bulunmuştur. Kapsül, biyofilm formasyonu ve HV görülme sıklığı sırasıyla %100, %79.2 ve %1.9 olarak saptanmıştır. Alfa hemolizin varlığı tespit edilmemiştir. entB (%96.2), ycfM (%86.8) ve mrkD (%83.0) genleri en yüksek düzeyde saptanan genler olmuştur. Araştırılan diğer genler; fimH-1 (%64.2), fyuA (%54.7), kpn (%49.1), ybtS (%41.5), irp-1(%41.5), irp-2 (%37.7), traT (%11.3) ve iutA (%5.7%) farklı sıklıklarda saptanmıştır. İzolatlarda iroN, rmpA, magA, hlyA ve cnf-1 genleri tespit edilmemiştir. Enterobaktin geni sideroforlar arasında, ycfM ve mrkD genleri adezinler arasında en sık saptanan virülans genleri olmuştur. Kapsül ve biyofilm oluşumu izolatlarda sıklıkla belirlenmiştir. Hipermukoviskozite yalnızca bir izolatta belirlenmiş ancak ilişkili genler tespit edilmemiştir. Sonuç olarak; alfa hemolizin üretimi, hlyA ve cnf-1 genleri hiçbir izolatta gözlenmemiştir. Hastane enfeksiyonu etkeni K.pneumoniae izolatlarında kapsül, adezinler, enterobaktin ve biyofilm oluşturma bu izolatların patojenitelerinin temelini oluşturmuştur. K.pneumoniae'ya bağlı hastane enfeksiyonlarının kontrolünde antibiyotik direncinin yanı sıra toksin ve invazyon yeteneğinin sürekli takip edileceği yeni çalışmalara ihtiyaç vardır.
Klebsiella pneumoniae is an opportunistic pathogen that commonly affects immunosuppressed patients and causes nosocomial infections. K.pneumoniae has a variety of virulence factors, especially capsule polysaccharide, hypermucoviscosity (HV), fimbriae, toxins and determinants for iron acquisition. The aim of this study was to detect the virulence factors in K.pneumoniae strains isolated from nosocomial infections in two years. Fifty three K.pneumoniae strains isolated from the samples of patients with nosocomial infections in the Medical Microbiology Laboratory of Selcuk University Faculty of Medicine Hospital between 2011 and 2013 were included in the study. Identification and antimicrobial susceptibilities of the isolates were performed by VITEK 2 automatic system. Biofilm formation,?-hemolysin, capsule and HV were investigated by phenotypic methods. Polymerase chain reaction (PCR) was used to detect virulence genes encoding adhesins (fimH-1, mrkD, kpn, ycfM), siderophores (entB: enterobactin, iutA: aerobactin, irp-1, irp-2, ybtS, fyuA: yersiniabactin, iroN: catechols receptor), protectines or invasins (rmpA, magA, traT) and toxins (hlyA, cnf-1). Of the 53 K.pneumoniae isolates,12 (22.6%) were isolated from in patients of reanimation intensive care unit, 8 (15.1%) medical oncology, 7 (13.2%) newborn intensive care unit and 26 (49%) other clinics. The distribution of the isolates according to the samples was as follows: urine (n 14), blood (n 13), wound (n 8), drainage fluid (n 10), broncho-alveolar lavage (n 7), and cerebrospinal fluid (n 1). Isolates which were resistant to meropenem were 5.7% and production of extended spectrum beta-lactamase (ESBL) was 71.7%. The capsule, biofilm formation, and HV were observed in 100%, 79.2%, and 1.9% of the isolates, respectively. Production of ?-hemolysin was not detected in any of the isolates. The genes; entB (96.2%), ycfM (86.8%), and mrkD (83.0%) showed high prevalence. The other genes were detected in different ratios: fimH-1 (64.2%), fyuA (54.7%), kpn (49.1%), ybtS (41.5%), irp-1(41.5%), irp-2 (37.7%), traT (11.3%) and iutA (5.7%). Virulence genes; iroN, rmpA, magA, hlyA and cnf-1 were not detected in any of the isolates. Enterobactin had the highest rate among siderophores, and ycfM and mrkD in adhesins. The capsule and biofilm formation were commonly found in the isolates. Hypermucoviscosity was only found in one isolate but associated genes were not detected. Alfa hemolysin production and hlyA gene were not determined. As a result, it seems that the basis of the pathogenicity of K.pneumoniae strains isolated from nosocomial infections are capsule, adhesins, enterobactin and ability of biofilm formation. There is a need for new studies for the continuous monitoring of toxin and invasion ability as well as antibiotic resistance in the control of hospital infection caused by K.pneumoniae.
Klebsiella pneumoniae is an opportunistic pathogen that commonly affects immunosuppressed patients and causes nosocomial infections. K.pneumoniae has a variety of virulence factors, especially capsule polysaccharide, hypermucoviscosity (HV), fimbriae, toxins and determinants for iron acquisition. The aim of this study was to detect the virulence factors in K.pneumoniae strains isolated from nosocomial infections in two years. Fifty three K.pneumoniae strains isolated from the samples of patients with nosocomial infections in the Medical Microbiology Laboratory of Selcuk University Faculty of Medicine Hospital between 2011 and 2013 were included in the study. Identification and antimicrobial susceptibilities of the isolates were performed by VITEK 2 automatic system. Biofilm formation,?-hemolysin, capsule and HV were investigated by phenotypic methods. Polymerase chain reaction (PCR) was used to detect virulence genes encoding adhesins (fimH-1, mrkD, kpn, ycfM), siderophores (entB: enterobactin, iutA: aerobactin, irp-1, irp-2, ybtS, fyuA: yersiniabactin, iroN: catechols receptor), protectines or invasins (rmpA, magA, traT) and toxins (hlyA, cnf-1). Of the 53 K.pneumoniae isolates,12 (22.6%) were isolated from in patients of reanimation intensive care unit, 8 (15.1%) medical oncology, 7 (13.2%) newborn intensive care unit and 26 (49%) other clinics. The distribution of the isolates according to the samples was as follows: urine (n 14), blood (n 13), wound (n 8), drainage fluid (n 10), broncho-alveolar lavage (n 7), and cerebrospinal fluid (n 1). Isolates which were resistant to meropenem were 5.7% and production of extended spectrum beta-lactamase (ESBL) was 71.7%. The capsule, biofilm formation, and HV were observed in 100%, 79.2%, and 1.9% of the isolates, respectively. Production of ?-hemolysin was not detected in any of the isolates. The genes; entB (96.2%), ycfM (86.8%), and mrkD (83.0%) showed high prevalence. The other genes were detected in different ratios: fimH-1 (64.2%), fyuA (54.7%), kpn (49.1%), ybtS (41.5%), irp-1(41.5%), irp-2 (37.7%), traT (11.3%) and iutA (5.7%). Virulence genes; iroN, rmpA, magA, hlyA and cnf-1 were not detected in any of the isolates. Enterobactin had the highest rate among siderophores, and ycfM and mrkD in adhesins. The capsule and biofilm formation were commonly found in the isolates. Hypermucoviscosity was only found in one isolate but associated genes were not detected. Alfa hemolysin production and hlyA gene were not determined. As a result, it seems that the basis of the pathogenicity of K.pneumoniae strains isolated from nosocomial infections are capsule, adhesins, enterobactin and ability of biofilm formation. There is a need for new studies for the continuous monitoring of toxin and invasion ability as well as antibiotic resistance in the control of hospital infection caused by K.pneumoniae.
Açıklama
Anahtar Kelimeler
Mikrobiyoloji, Hastane enfeksiyonu, Hospital infection, Klebsiella pneumoniae, Klebsiella pneumoniae
Kaynak
Mikrobiyoloji Bülteni
WoS Q Değeri
Scopus Q Değeri
Cilt
51
Sayı
4
Künye
Kuş, H., Arslan, U., Dağı, H. T., Fındık, D. (2017). Hastane Enfeksiyonu Etkeni Klebsiella pneumoniae İzolatlarında Çeşitli Virülans Faktörlerinin Araştırılması. Mikrobiyoloji Bülteni, 51(4), 329-339.
