Radboudumc-CWZ Center of Expertise for Mycology, Nijmegen, The Netherlands.
Canisius-Wilhelmina Hospital (CWZ)/Dicoon, Nijmegen, The Netherlands.
Mycoses. 2024 Jun;67(6):e13752. doi: 10.1111/myc.13752.
Candida auris is an emerging multidrug-resistant yeast, frequently causing outbreaks in health care facilities. The pathogen persistently colonises human skin and inanimate surfaces such as catheters, aiding to its spread. Moreover, colonisation is a risk factor to develop invasive infection.
We investigated 61 C. auris strains isolated from non-sterile human body sites (n = 53) and the hospital environment (n = 8), originating from four different centres in a single Brazilian state.
Antifungal susceptibility testing (AFST) against common antifungals was performed, and resistance-associated genes were evaluated. Genetic relatedness was investigated with short tandem repeat (STR) genotyping and validated with whole-genome sequencing (WGS) single nucleotide polymorphism (SNP) analysis.
Antifungal susceptibility testing demonstrated that all isolates were susceptible to azoles, echinocandins and amphotericin B. No mutations were detected in ERG11 and FKS1 genes. With STR typing, isolates were allocated to clade IV and appeared closely related. This was confirmed by WGS SNP analysis of 6 isolates, which demonstrated a maximal difference of only 41 SNPs between these strains. Furthermore, the Brazilian isolates formed a distinct autochthonous branch within clade IV, excluding recent introductions from outside the country. A molecular clock analysis of clade IV isolates from various countries suggests that early in the previous century there was a unique event causing environmental spread of a C. auris ancestor throughout the Latin-American continent, followed by human introduction during the last decades.
We report the emergence of C. auris patient colonisation in multiple centres by fluconazole-susceptible clade IV close-related strains in Pernambuco State, Brazil.
耳念珠菌是一种新兴的耐多药酵母，经常在医疗机构引起暴发。该病原体持续定植于人体皮肤和无生命的表面，如导管，有助于其传播。此外，定植是发生侵袭性感染的一个危险因素。
我们调查了来自巴西一个州的四个不同中心的 61 株非无菌人体部位（n=53）和医院环境（n=8）分离的耳念珠菌。
对常见抗真菌药物进行了抗真菌药敏试验（AFST），并评估了耐药相关基因。通过短串联重复（STR）基因分型研究了遗传相关性，并通过全基因组测序（WGS）单核苷酸多态性（SNP）分析进行了验证。
药敏试验表明所有分离株均对唑类、棘白菌素类和两性霉素 B 敏感。未在 ERG11 和 FKS1 基因中检测到突变。通过 STR 分型，将分离株分配到 IV 群，并且显示出密切相关。对 6 株分离株的 WGS SNP 分析证实了这一点，这些菌株之间的最大差异仅为 41 个 SNP。此外，巴西分离株在 IV 群内形成了一个独特的本土分支，排除了近期从国外传入的菌株。对来自不同国家的 IV 群分离株的分子钟分析表明，在上个世纪早期，有一个独特的事件导致耳念珠菌祖先在拉丁美洲大陆的环境中传播，随后在过去几十年中被人类引入。
我们报告了在巴西伯南布哥州，多个中心出现了对氟康唑敏感的 IV 群近缘株耳念珠菌患者定植。
