Sharma Cheshta, Muralidhar Sumathi, Xu Jianping, Meis Jacques F, Chowdhary Anuradha
Department of Medical Mycology, Vallabhbhai Patel Chest Institute, University of Delhi, Delhi, India.
Mycoses. 2014 Sep;57(9):544-52. doi: 10.1111/myc.12193. Epub 2014 Apr 3.
We investigated the prevalence of vulvovaginal candidiasis due to C. africana in an STD clinic in India and analysed the genetic relatedness of these C. africana isolates with those outside India. A total of 283 germ-tube-positive yeasts were identified by VITEK2. Molecular characterisation of all isolates was carried out by hwp1-gene-specific PCR. Of 283 germ-tube-positive yeast isolates, four were identified as C. africana using hwp1-gene-specific PCR. All hwp1 PCR positive C. africana were subjected to antifungal susceptibility testing, ITS and D1/D2 region sequencing and were typed by using MLST approach. Similar to C. africana isolates from the United Kingdom and unlike those from Africa, the Indian C. africana grew at 42°C. Sequencing of eight gene fragments in MLST identified all four strains to have different genotypes not reported previously. Furthermore, though the Indian C. africana isolates were susceptible to most of the 14 tested antifungal drugs, differences in susceptibility were observed among the four strains. Our results indicate genetic and phenotypic heterogeneity among C. africana from different geographical regions. Due to lack of data on epidemiology and genetic variability of this under-reported yeast, more studies using molecular methods are warranted.
我们在印度的一家性传播疾病诊所调查了非洲念珠菌引起的外阴阴道念珠菌病的患病率,并分析了这些非洲念珠菌分离株与印度以外地区分离株的遗传相关性。通过VITEK2共鉴定出283株芽管阳性酵母。所有分离株的分子特征通过hwp1基因特异性PCR进行。在283株芽管阳性酵母分离株中,使用hwp1基因特异性PCR鉴定出4株为非洲念珠菌。所有hwp1 PCR阳性的非洲念珠菌均进行了抗真菌药敏试验、ITS和D1/D2区域测序,并采用多位点序列分型方法进行分型。与来自英国的非洲念珠菌分离株相似,与来自非洲的不同,印度的非洲念珠菌在42°C下生长。多位点序列分型中八个基因片段的测序确定所有四株菌株具有以前未报道的不同基因型。此外,尽管印度的非洲念珠菌分离株对14种测试抗真菌药物中的大多数敏感,但四株菌株之间观察到药敏差异。我们的结果表明不同地理区域的非洲念珠菌之间存在遗传和表型异质性。由于缺乏关于这种报告不足的酵母的流行病学和遗传变异性的数据,有必要使用分子方法进行更多研究。