UMI 233 IRD-UM INSERM U1175 TransVIHMI, Infections mycosiques et parasitaires liées au VIH, Laboratoire de Parasitologie et de Mycologie Médicale, UFR Pharmacie, Montpellier, France.
Mycoses. 2022 Jan;65(1):88-96. doi: 10.1111/myc.13389. Epub 2021 Nov 23.
Cryptococcus neoformans and Cryptococcus gattii species complexes are pathogens causing cryptococcal meningitis, a fungal infection that leads to death unless treated. Worldwide, it is estimated to kill over 180,000 individuals annually.
We aim to investigate the molecular diversity of C. gattii isolates from strains isolated from 1995 to the present day from different continents.
In this study, we analysed the molecular diversity by MLST and antifungal susceptibility by using the broth microdilution method according to the CLSI M27-A4 protocol of a total of 26 strains from Cryptococcus gattii species complex from both clinical and environmental sources.
Genotyping showed that most of the strains (17/26; 65.4%) belonged to serotype B and were distributed between three genotypes: VGI (13/17; 76.5%), VGII (3/17; 17.6%) and VGVI (1/17; 5.9%). The serotype C strains (9/26; 34.6%) were distributed between the VGIII (1/9; 11.1%) and VGIV (8/9; 88.9%) genotypes. The 26 strains belonged to 17 different MLST subtypes, and we highlight four new MLST genotypes (ST553, 554, 555 and 556). The two environmental strains were identified as serotype B and genotype VGI, but were of ST 51 and 154. All isolates have wild-type MIC of fluconazole and flucytosine. Regarding amphotericin B, five VGI strains showed MICs to AMB equal to 1 µg/ml, and according to the ECV for these genotypes, they were considered non-wild-type strains.
The current study reveals the genetic diversity and new sequence types among strains from the C. gattii complex species.
新型隐球菌和格特隐球菌种复合体是引起隐球菌性脑膜炎的病原体，这是一种真菌感染，如果不治疗，会导致死亡。据估计，全世界每年有超过 18 万人因此死亡。
我们旨在研究从 1995 年至今来自不同大洲的菌株中分离出的格特隐球菌的分子多样性。
在这项研究中，我们通过 MLST 分析了分子多样性，并根据 CLSI M27-A4 方案使用肉汤微量稀释法分析了抗真菌药物敏感性，该方案共涉及来自临床和环境来源的格特隐球菌种复合体的 26 株菌株。
基因分型显示，大多数菌株（26 株中的 17 株；65.4%）属于血清型 B，分布在三个基因型中：VGⅠ（13/17；76.5%）、VGⅡ（3/17；17.6%）和 VGVI（1/17；5.9%）。血清型 C 菌株（26 株中的 9 株；34.6%）分布在 VGⅢ（1/9；11.1%）和 VGⅣ（8/9；88.9%）基因型中。26 株菌株属于 17 种不同的 MLST 亚型，我们强调了四种新的 MLST 基因型（ST553、554、555 和 556）。两种环境菌株被鉴定为血清型 B 和基因型 VGⅠ，但 ST 为 51 和 154。所有分离株对氟康唑和氟胞嘧啶的 MIC 均为野生型。关于两性霉素 B，5 株 VGⅠ 菌株对 AMB 的 MIC 等于 1μg/ml，根据这些基因型的 ECV，它们被认为是非野生型菌株。
本研究揭示了格特隐球菌复合体种菌株之间的遗传多样性和新的序列类型。
