微卫星基因分型法分析生殖器白念珠菌感染的传播特点

目的 建立适用于株间鉴别的白念珠菌快速微卫星基因分型方法,探索生殖器白念珠菌感染特点.方法 采集39例女性和27例男性生殖器念珠菌病患者生殖器、肛管和口腔的白念珠菌分离株.以三色荧光标记引物,PCR扩增白念珠菌保守基因CDC3、EF3和HIS3微卫星序列,经聚丙烯酰胺凝胶电泳,行微卫星多态性基因分型.结果 三基因联合分析显示,男女生殖器白念珠菌感染者共获18种基因型,主要致病菌株基因型为116:124、122:131、160:200,占感染者的50%以上.3种共有基因型占71%.女性患者中肛管部位菌株基因型与生殖器部位完全一致的占80%,男性则仅占3.8%.女性患者口腔部位的菌株基因型与生殖器部位完全一致的仅占2.7%,男性未见口腔和生殖器一致的菌株基因型.71%的夫妻共患者间生殖器白念珠菌基因型完全相同,其中80%的致病菌株基因型为两性皆感染的主要致病性白念珠菌.结论 改良的白念珠菌微卫星多态性基因分型法能够特异、准确、稳定和快速地进行菌株间鉴别.生殖器白念珠菌感染存在优势基因型.

Study on the transmission characteristics of genital Candida albicans infection by a rapid microsatellite genotyping

Objectives In order to develop a rapid microsatellite genotyping assay for inter-strain differentiation of Candida albicans isolates and understand the transmission characteristics of the infections. Methods DNA was extracted from C. albicans isolates from genitals, anal canals and oral cavities of 39 women and 27 men with genital candidiasis. The microsatellite sequences in stabel genes(CDC3, EF3 and HIS3) were amplified by a fluorescence labeled PCR. Fluorescent signals were read with an automatic se- quencer, and the data were collected with GeneScan software followed by genotyping with Genotyper soft- ware to analyze polymorphic microsatellite loci. Results Combined analysis of the 3 microsatellite markers showed 18 gene allele associations in C. albicans from genital sites of all men and women, including 10 in women, 11 in men and 3 in both. The allele associations of dominant pathogenetic strains for both sexes were 116:124, 122:131,160:200, which covered 50% of pathogenetic infection. Three common allele associations for both sexes covered 71% of all infections. Genitals and anal canals shared strains of same allele associations in 80% of women and in only 3.8% of men. The strains of same allele associations were identified in both genitals and mouth in 2.7% of women but in none of men. In their genital sites 71% of couples shared the same allele strains, of which 80% were the dominant pathogenetic strains identified in both sexes. Conclusions The improved microsatellite genotyping assay is useful for rapid differentiation, identification of infective source, and contact tracing of C. albicans infection. There are pathogenetic C. albi- cans strains with predominant allele associations in genital infections.