Application of PCR-reverse dot blot hybridization in the diagnosis of vulvovaginal candidiasis and the detection of Candida albicans drug-resistant genes / 临床检验杂志

ABSTRACT

Objective To evaluate the application value of PCR-reverse dot blot hybridization in the identification of Candida and the detection of Candida albicans drug-resistant genes.Methods The vaginal secretion samples from 285 patients with candidal vaginitis and 50 healthy women were collected.The identification of Candida species and their drug susceptibility were detected by the bioMérieux Yeast identification cards and MIC method(Zhengzhou Antu kit),respectively.The identification of Candida species and the mutation of Candida albicans,drug-resistant genes were also detected by the Shenzheng Yaneng test kit(PCR-reverse dot blot hybridization).The drug-resistant genes were also identified by PCR and nucleic acid sequencing.Based on the culture identification,MIC method and nucleic acid sequencing as the contrast methods,the sensitivity,specificity and accuracy of PCR-reverse dot blot hybridization in the identification of Candida species and the mutation detection of Candida albicans drug-resistant genes were evaluated.Results Compared with the bioMérieux Yeast identification method,the sensitivity,specificity,positive predictive value,negative predictive value and total coincidence rate of PCR-reverse dot blot hybridization for detecting six kinds of Candida species,including Candida albicans,Candida glabrata,Candida tropicalis,Candida parapsilosis,Candida krusei and Candida guilliermondii,were above 95％,96％,96％,98％ and 97％,respectively.There was no significant difference in detecting six kinds of Candida species between the two methods (x2 =0.44,0,0,0,0 and 0,respectively,P ＞ 0.05),and there was good consistency between them (Kappa ＞ 0.9).Compared with the MIC method,the sensitivity,specificity,positive predictive value,negative predictive value and total coincidence rate of PCR-reverse dot blot hybridization for detecting the drug resistance of Candida albicans were 98％,88％,98％,88％ and 96％,respectively.There was no significant difference in detecting the drug resistance of Candida albicans between the two methods (x2 =0.17,P ＞ 0.05),and there was good consistency between them (Kappa ＞ 0.8).The results of PCR-reverse dot blot hybridization in detecting the mutation sites of six kinds of Candida albicans drug-resistant genes were 100％ of coincidence with that of the nucleic acid sequencing method.Conclusion The PCR-reverse dot blot hybridization has high consistency with the culture method and the nucleic acid sequencing method in the identification of Candida species and the mutation detection of Candida albicans drug-resistant genes,which is more early and rapid than the traditional detection methods,and may be applied to the auxiliary diagnosis of vulvovaginal candidiasis (VVC).