The Characteristices Of Identification,Antifungal Agents Susceptibility And Multilocus Sequence Typing Of Pathogenic Fungi From Candidaemia In Jiangxi Province

Objectives : 1.The identification,molecular identification and drug susceptibility to antifungal drugs of pathogenic fungi in patients with candidaemia in the First Affiliated Hospital of Nanchang University,which will understand the distribution of Candida spp and the resistance to antifungal drugs,the epidemiological characteristics of pathogenic fungi of Candida spp in Jiangxi Province,and to guide the use of clinical antifungal drugs.2.Candida albicans and Candida tropicalis were carried out by using multiple sequence typing to genotype,which will understand the genotype characteristics of common pathogens of Candida albicans in Jiangxi Province.Methods: Blood culture positive samples were collected and fungal morphology such as elongated hyphae or spores or pseudohyphae was observed under an optical microscope.The specimens were incubated with Sabouraud Dextrose Agar Medium(SDA),and the colony is isolated and purified,which was a slight sticky colony with white or milky white surfaces on the plate.The strain was preliminarily screened with CHROMagar medium and was stored at-80℃.The identification was performed by two different moecluar regions,including internal transcribed spacer(ITS)region and the 26 S rRNA gene(D1/D2 domain).The antifungal susceptibility testing was conducted according to the guidelines of M27-A3 standard recommended by the Clinical Laboratory Standard Institute(CLSI).Multilocus sequence typing(MLST)was performed genotypes of Candida albicans and Candida tropicalis.Results:Fifty-two Candida spp were collected,which includes 17 Candida tropicalis,accounted for 32.7%;16 Candida albicans,accounting for 30.8%;16Candida parapsilosis complex,accounting for 30.8%;3 Candida glabrata,accounting for 5.7%.There are 14 Candida parapsilosis sensu stricto and 2 Candida metapsilosis in 16 Candida parapsilosis complex,accounting for 26.9% and 3.9%.6 Candida spp.,including 1 Candida albicans and 5 Candida tropicalis,were resistant tofluconazole.7 Candida spp.,including 4 Candida albicans and 3 Candida tropicalis,were no-WT to itraconazole.4 Candida spp.,including 3 Candida albicans and 1 Candida albicans,were resistant to voriconazole,4 Candida spp.,including 3Candida albicans and 1Candida tropicalis,were no-WT to posaconazole.2 Candida spp.,including 1 Candida albicans and 1 Candida tropicalis,were cross-resistant to fluconazole,voriconazole and itraconazole.All 17 Candida tropicalis generated 13 new diploid sequence types(DSTs).Whereas 16 Candida albicans isolates shared 16 new DSTs.Conclusions:1.Candida albicans,Candida tropicalis and Candida glabrata are still the main pathogen,and Candida tropicalis is the most common pathogen from candidaemia in Nanchang,Jiangxi Province.2.The pathogenic fungi collected from candidaemia are the most sensitive/WT to,caspofungin,micafungin and amphotericin B,but are the less sensitive/WT to fluconazole,itraconazole,voriconazole,especially fluconazole and voriconazole.3.The diploid sequence types of common pathogenic fungi,including Candida tropicalis and Candida albicans,collected from candidaemia are new DSTs in Nanchang,Jiangxi Province,epidemic clonal strains were not found.