Ngouana Thierry Kammalac, Drakulovski Pascal, Krasteva Donika, Toghueo Rufin Kuipou, Kouanfack Charles, Reynes Jacques, Delaporte Eric, Boyom Fabrice Fekam, Mallié Michèle, Bertout Sébastien
Clinical Biology Laboratory, Yaoundé Central Hospital, Cameroon.
IRD UMI 233 TransVIHMI - UM INSERM U1175 〈〈 TransVIHMI 〉〉 Laboratoire de Parasitologie et Mycologie Médicale, UFR Pharmacie, Université Montpellier, France.
Med Mycol. 2017 Jul 1;55(5):546-554. doi: 10.1093/mmy/myw108.
The molecular epidemiology and the antifungal susceptibility profiles of Candida albicans are scarce in Cameroon. Authors studied the genetic diversity and the antifungal susceptibility of C. albicans isolates from Yaoundé HIV-infected patients. Clinical isolates were obtained by mycological diagnosis of oropharyngeal swabs, stools, urine, and vaginal swabs from patients. C. albicans isolates were confirmed by the Light cycler real-time PCR of the ITS1 region of the 5.8s ribosomal DNA. The ABC genotypes and the Hwp1 gene amplification were carried out with specific primers. Microsatellite length polymorphism of HIS3, CDC3, and EF3 microsatellites was analysed. The antifungal susceptibility testing was carried out by the CLSI broth microdilution M27-A3 and M27-S4 protocols. The minimal inhibitory concentration (MIC) results were interpreted according to updated clinical breakpoints (CBPs) recommended by the CLSI or epidemiological cut-off values (ECVs). One hundred and thirteen (113) isolates were obtained from the analysis of 1218 samples. The ABC genotyping showed 79 (69.91%) genotype A, 24 (21.23%) genotype B, and 10 (8.84%) genotype C. The Hwp1 gene amplification provided a newly observed genetic polymorphism, named H and 5 genotypes described (H1-H5). The microsatellite analysis generated 65 molecular types. All the isolates were susceptible to amphotericin B (MIC ≤ 1 μg/ml); 79.64% of isolates were wild type to itraconazole (MIC ≤ 0.12 μg/ml); and 86.72% of isolates were susceptible to fluconazole (MIC ≤ 2 μg/ml). These results highlight the important genetic diversity of C. albicans isolates among Yaoundé HIV-infected patients and bring clues for the comprehension of the molecular epidemiology of the yeast in Cameroon.
在喀麦隆，白色念珠菌的分子流行病学及抗真菌药敏谱的相关研究较少。作者对雅温得感染HIV患者分离出的白色念珠菌的遗传多样性及抗真菌药敏性进行了研究。临床分离株通过对患者的口咽拭子、粪便、尿液及阴道拭子进行真菌学诊断获得。白色念珠菌分离株通过对5.8s核糖体DNA的ITS1区域进行Light cycler实时PCR进行确认。使用特异性引物进行ABC基因型及Hwp1基因扩增。分析了HIS3、CDC3和EF3微卫星的微卫星长度多态性。抗真菌药敏试验按照CLSI肉汤微量稀释法M27 - A3和M27 - S4方案进行。根据CLSI推荐的更新临床折点（CBP）或流行病学截断值（ECV）解释最小抑菌浓度（MIC）结果。对1218份样本进行分析后获得了113株分离株。ABC基因分型显示79株（69.91%）为A基因型，24株（21.23%）为B基因型，10株（8.84%）为C基因型。Hwp1基因扩增发现了一种新观察到的遗传多态性，命名为H以及描述的5种基因型（H1 - H5）。微卫星分析产生了65种分子类型。所有分离株对两性霉素B敏感（MIC≤1μg/ml）；79.64%的分离株对伊曲康唑为野生型（MIC≤0.12μg/ml）；86.72%的分离株对氟康唑敏感（MIC≤2μg/ml）。这些结果突出了雅温得感染HIV患者中白色念珠菌分离株重要的遗传多样性，并为理解喀麦隆该酵母菌的分子流行病学提供了线索。
