Asadzadeh Mohammad, Ahmad Suhail, Al-Sweih Noura, Khan Ziauddin
Department of Microbiology, Faculty of Medicine, Kuwait University , Safat, Kuwait .
Microb Drug Resist. 2017 Dec;23(8):966-972. doi: 10.1089/mdr.2016.0336. Epub 2017 Mar 29.
Fluconazole resistance among clinical Candida parapsilosis isolates is an emerging problem in many countries, including Kuwait. Resistance to fluconazole is mediated by amino acid substitutions in ERG11 and/or by overexpression of efflux pumps MDR1 and CDR1. Clinical C. parapsilosis sensu stricto isolates (n = 442) were tested for susceptibility to fluconazole by Etest, Vitek II, and broth microdilution methods. ERG11 was analyzed from fluconazole-resistant, fluconazole-susceptible dose-dependent, and selected fluconazole-susceptible isolates. Of 442 C. parapsilosis isolates, 425, 2, and 15 were identified as susceptible, susceptible dose-dependent, and resistant to fluconazole, respectively. PCR sequencing of ERG11 identified Y132F mutation in 5 of 11 fluconazole-resistant isolates available for analysis. This mutation was absent in 46 fluconazole-susceptible and 2 fluconazole-susceptible dose-dependent isolates. A multiplex allele-specific PCR was developed for detection of Y132F mutation in ERG11, and results correlated perfectly with PCR sequencing data for ERG11 codon 132 for all isolates analyzed. Detection of resistance in 15 and reduced susceptibility in 2 among 442 C. parapsilosis isolates highlights emerging resistance to fluconazole in Kuwait. The Y132F mutation in ERG11 was found in 5 of 11 (45%) fluconazole-resistant isolates only. Detection of fluconazole resistance in C. parapsilosis will help in proper management of patients infected with this species.
包括科威特在内，许多国家临床分离的近平滑念珠菌对氟康唑耐药已成为一个新出现的问题。对氟康唑的耐药性是由ERG11中的氨基酸替换和/或外排泵MDR1和CDR1的过表达介导的。采用Etest、Vitek II和肉汤微量稀释法对临床近平滑念珠菌狭义亚种分离株（n = 442）进行氟康唑敏感性检测。对氟康唑耐药、氟康唑敏感剂量依赖性和部分氟康唑敏感分离株进行ERG11分析。在442株近平滑念珠菌分离株中，分别有425株、2株和15株被鉴定为对氟康唑敏感、氟康唑敏感剂量依赖性和耐药。对11株可用于分析的氟康唑耐药分离株中的5株进行ERG11的PCR测序，发现存在Y132F突变。46株氟康唑敏感和2株氟康唑敏感剂量依赖性分离株中不存在该突变。开发了一种多重等位基因特异性PCR用于检测ERG11中的Y132F突变，对所有分析分离株而言，其结果与ERG11密码子132的PCR测序数据完全相关。442株近平滑念珠菌分离株中有15株耐药和2株敏感性降低，这凸显了科威特氟康唑耐药问题的出现。仅在11株（45%）氟康唑耐药分离株中的5株中发现了ERG11中的Y132F突变。检测近平滑念珠菌对氟康唑的耐药性将有助于对感染该菌种的患者进行妥善管理。
