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Objective@#To investigate genotypes and drug susceptibility of the 100 strains of Candida glabrata isolated from 100 women (including 50 pregnant women) in order to study the drug-resistance and gene polymorphism, and to investigate the correlation of drug-resistance, gestation and gene polymorphism.@*Methods@#Multilocus sequence typing (MLST) technique was introduced to identify sequences of 6 housekeeping genes from 100 isolates of Candida glabrata. The results were compared with sequence information in MLST databases by Clustalx software to determine a strain allelic profile and sequence type (ST). Drawing the phylogenetic tree by weighted paired group average method and the minimal spanning tree method of MEGA6.0 software, the microevolution and relationship between different strains were analyzed. ATB FUNGUS semi-automatic system was used to test the drug susceptibility. Fisher analysis method was used to analyze the correlation between the genotypes and pregnancy.Ridit analysis method was used to analyze the correlation between the genotypes and drug susceptibility.@*Results@#The 100 isolates belonged to 34 clone sequences. There were 53 isolates belonged to ST-7 ( 26 isolates of pregnancy), 7 isolates belonged to ST-3 (3 isolates of pregnancy), 6 isolates belonged to ST-19 (5 isolates of pregnancy ), 3 isolates belonged to ST-15 (1 isolate of pregnancy), 2 isolates belonged to ST-10 (2 isolates of pregnancy), 1 isolate belonged to the other types of ST. Total of 100 isolates of Candida glabrata were 100% sensitive to fluorocytosine and amphotericin. The effect of itraconazole was poor with the sensitive rate of 20%. The resistance rates of fluconazole and voriconazole were 4% and 1% respectively. All genotypes were sensitive to voriconazole except ST-X1. In the correlation between genotype and itraconazole resistance, ST-7 as the standard group, the Ridit values in the group of ST-15, ST-19 and other types of ST were not included the mean Ridit value of the standard group in itraconazole (0.5). The system evolution tree was built using the neighbor-joining method (NJ) . All genotypes could be divided into 3 groups, as Ⅰ, Ⅱ, Ⅲ. Group Ⅰ had 44 cases, group Ⅱ had 53 cases , group Ⅲ had 3 cases . All the collected clinical strains had small genetic distances during molecular evolution.@*Conclusions@#ST-7 was the dominant genotype in Guiyang. No correlation between different STs and patients′ pregnancy was found. The different drug susceptibility in itraconazole between ST-7, ST-15, ST-19 and other STs were found. The Candida glabrata associated with VVC showed highly discrimative diversity. However, the phylogenic analysis exhibited genetic similarity among the strains studied.(Chin J Lab Med, 2018, 41: 596-600)
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Objective:To investigate the azole susceptibility of Candida albicans (C. albicans) from vulvovaginal candidosis patients and to analyze the relationship between ERG11 gene mutations in these isolates and azole resistance. Methods:Three hundred and two clinical isolates of Candida species were collected. Azole susceptibility was tested in vitro in microdilution studies. The ERG11 genes of 17 isolates of C. albicans (2 susceptibles, 5 dose-dependent resistants and 10 resistants) were amplified and sequenced. Results:Of the 302 isolates collected, 70.2%were C. albicans, of which 8.5%, 3.8%and 4.2%were resistant to fluconazole, itraconazole and voriconazole, respectively. In total, 27 missense mutations were detected in ERG11 genes from resistant/susceptible dose-dependent isolates. Among them, Y132H, A114S, and Y257H substitutions were most prevalent and were known to cause fluconazole resistance. G464S and F72S also has been proved to cause fluconazole resistance. Two novel substitutions (T285A, S457P) in hotspot regions were identified. Conclusions:Twenty seven mutations in the ERG11 gene were identified in azole-resistant C. albicans isolates, which indicated a possible relation with the increase in resistance to azole drugs and the recurrence of vulvovaginal candidosis. The relationship of two novel substitutions (T285A, S457P) with fluconazole resistance needs to be further verified by site-directed mutagenesis.
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Objective: To investigate the azole susceptibility of Candida albicans ( C. albicans) from vulvovaginal candidosis patients and to analyze the relationship between ERG11 gene mutations in these isolates and azole resistance. Methods: Three hundred and two clinical isolates of Candida species were collected. Azole susceptibility was tested in vitro in microdilution studies. The ERG11 genes of 17 isolates of C. albicans (2 susceptibles, 5 dose-dependent resistants and 10 resistants) were amplified and sequenced. Results: Of the 302 isolates collected, 70.2% were C. albicans, of which 8.5%, 3.8% and 4.2% were resistant to fluconazole, itraconazole and voriconazole, respectively. In total, 27 missense mutations were detected in ERG11 genes from resistant/susceptible dose-dependent isolates. Among them, Y132H, A114S, and Y257H substitutions were most prevalent and were known to cause fluconazole resistance. G464S and F72S also have been proved to cause fluconazole resistance. Two novel substitutions (T285A, S457P) in hotspot regions were identified. Conclusions: Twenty seven mutations in the ERG11 gene were identified in azole-resistant C. albicans isolates, which indicated a possible relation with the increase in resistance to azole drugs and the recurrence of vulvovaginal candidosis. The relationship of two novel substitutions (T285A, S457P) with fluconazole resistance needs to be further verified by site-directed mutagenesis.
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The prevalence of vulvovaginal candidosis (VVC) caused by C. non-albicans tends to increase, recently. The aim of this study was to obtain data about proportion and clinical characteristic of C. non-albicans VVC at dr. Cipto Mangunkusumo General Hospital, Jakarta. This is a cross-sectional study on all female patients with symptoms of VVC visiting Obstetri-gynaecology and Dermatovenereology outpatient clinics at dr. Cipto Mangunkusumo General Hospital, Jakarta. All subjects had positive Gram stain, showed Candida spp. on culture with CHROMagar Candida, and had no other specific genital infections. Sixty nine subjects aged 26–44 years old (averaged 29 years old) were included in this study. Candida non-albicans was found in 30.4% subject, and consisted of: C. glabrata (61.9%), C. tropicalis (28.6%) and C. parapsilosis (9.5%). We found that C. non-albicans VVC infections are more common in women above 45 years old, using non-hormonal contraceptives, whose sexual partner has erythema and pruritus in glands penis, and having the disease for more than 1 year. No differences in clinical symptoms were noted between C. albicans and C. non-albicans infection. We concluded from this study that the proportion of C. non-albicans infections at dr. Cipto Mangunkusumo General Hospital, Jakarta, with C. glabrata represents the most prevalent species. No characteristic clinical symptoms were found from the subjects with C. non-albicans VVC when compared with those infected by C. albicans.