Molecular Biologic Method Identification And Drug Susceptibility Research On Hematologic Malignancies With Invasive Fungal Infections

Objective:.1. Along with the speedy development and widely application of fungus drugs, drugresistance is serious. Analyzing the pathogen of deep fungal infection and monitoring drugresistance are very important for instructing clinical doctors to use antibiotic properly.2. There is a growing trend of invasive fungus infection. Establishing molecular biologicdiagnosis method for hematologic malignancies with invasive fungal infections, to earlydiagnosis and immediate treatment are very important.Methods:1.PCR-RFLP and DNA sequencing were used to isolated DNA from 500 whole bloodsamples, obtained from high risk fungal patients with hematologic malignancies ,comparedwith conventional blood cultures.2.ATB Identification Card was used for fungi identification and ATBFUNGUS strips wasused for drug susceptibility tests, to analyze fungal drug resistance,for amphotericin,5-flucytosine,fluconazole,ftraconazole and voriconazole.Results:1. 115 strains were detected from 500 samples through routine blood samples,the positiverate was 22.1% through PCR-RFLP and DNA sequencing. Compared with routine bloodculture method it is more sensitive and accurate in clinical application. The results werecompared with that of traditional method was similar. Candida albicans, Candida parapsilosis ,Candida glabrata, Candida Krusei, Candida parapsilosis.2. The majority isolated fungus strains were C.albicans, about 41.7%. The sensitive ratesof fungi to amphotericin,5-flucytosine,fluconazole,flraconazole and voriconazole wererespectively 100%,97.22%,68.50%,77.78% and 81.48%. The pathogenic fungi were highlysensitve to Amphotericin-B and 5-Flurocytosines with the sensitive rates of about 0% and2.78%. Fluconazole was lowest with 31.50%.Conclusions:1. PCR-RFLP, which can be carried out within one day compared with conventionalculture method, is a rapid, sensitive and specific method to the identification of fugal infection. So there is the clinical application value for early fugal infection diagnosis.2.Candida albieans and Candida tropicalis are the main pathogens responsible for fungiinfection and highly sensitive in vitro to Amphotefiein-B and 5-fluorocytosine．the effectivedrugs for treatment of deep fungus infection．...