Laboratório de Micologia, Instituto Nacional de Infectologia Evandro Chagas, Fundação Oswaldo Cruz, Fiocruz, Av. Brazil 4365 - Manguinhos, Rio de Janeiro, RJ, 21045-900, Brazil.
The Pathogen and Microbiome Institute, Northern Arizona University, Flagstaff, AZ, USA.
Curr Microbiol. 2024 Sep 3;81(10):338. doi: 10.1007/s00284-024-03854-y.
During the COVID-19 pandemic, fungal infections, especially pulmonary aspergillosis, mucormycosis, and invasive candidiasis, have emerged as a significant health concern. Beyond Candida albicans, the most common cause of invasive candidiasis, other rare ascomycetous yeast species have been described in tertiary care units, potentially posing a broader health threat. We have isolated, from September 2020 to June 2021, nine Diutina catenulata strains from urine samples of six patients. This was intriguing as this fungus had not been previously identified in our institution, nor after June 2021. Therefore, we decided to outline the clinical features of the patients with this rare pathogen, to describe phenotypic characteristics, including antifungal susceptibility profiles, of this yeast species and to identify the genetic makeup through whole-genome sequencing analysis to evaluate if this was a cluster of genetically similar D. catenulata isolates in our institution. The strains were identified through MALDI-TOF MS analyses and Sanger sequencing of two rDNA regions. All patients yielding D. catenulata from urine samples needed ventilator support and used urinary catheters during hospitalization for treatment of COVID-19. None of them had received COVID-19 vaccines. Morphological and biochemical profiles of the nine strains were largely consistent, although fluconazole susceptibility varied, ranging from 4 to 32 μg/mL. Phylogenomic analysis revealed minimal genetic variation among the isolates, with low intrapopulation variation, supported by the identification of only 84 SNPs across all strains. Therefore, we propose that the yeast strains isolated were part of a cluster of D. catenulata funguria in the context of COVID-19.
在 COVID-19 大流行期间,真菌感染,尤其是肺曲霉病、毛霉病和侵袭性念珠菌病,已成为一个重大的健康问题。除了最常见的侵袭性念珠菌病病原体白念珠菌外,其他罕见的子囊菌酵母种也在三级护理病房中被描述,可能构成更广泛的健康威胁。我们从 2020 年 9 月至 2021 年 6 月,从 6 名患者的尿液样本中分离出了 9 株链状迪图纳酵母。这很有趣,因为这种真菌以前在我们的机构中没有被发现,也没有在 2021 年 6 月之后被发现。因此,我们决定概述携带这种罕见病原体的患者的临床特征,描述该酵母种的表型特征,包括抗真菌药敏谱,并通过全基因组测序分析来鉴定其遗传结构,以评估这是否是我们机构中一组遗传上相似的链状迪图纳酵母分离株。通过 MALDI-TOF MS 分析和两个 rDNA 区域的 Sanger 测序鉴定了这些菌株。所有从尿液样本中产生链状迪图纳酵母的患者都需要呼吸机支持,并在 COVID-19 治疗期间使用导尿管。他们都没有接种 COVID-19 疫苗。尽管氟康唑敏感性有所不同,范围为 4 至 32μg/ml,但 9 株菌的形态和生化特征基本一致。系统发育基因组分析显示,这些分离株之间的遗传变异很小,种内变异也很小,这一结果得到了所有菌株中仅发现 84 个单核苷酸多态性的支持。因此,我们认为,从 COVID-19 患者尿液中分离的酵母菌株是链状迪图纳酵母菌尿症的一部分。