医院内侵袭性假丝酵母菌感染的流行病学趋势及变迁

目的研究北京朝阳医院2000-2010年分离的侵袭性假丝酵母菌,了解医院侵袭性假丝酵母菌感染的流行病学趋势及变迁。方法对侵袭性假丝酵母菌进行菌种收集统计;采用科玛嘉显色培养基和VITEK-2Com-pact YST卡进行菌种初筛鉴定;用26SrDNA D1/D2区SSCP图谱分析进行精准分子鉴定;采用CAI区SSCP图谱和GeneScan相结合对侵袭性白色假丝酵母菌进行基因分型;药敏试验采用ATB FUNGUS 3系统和E-test对5种抗真菌药进行MIC值测定。结果 2000-2010年共检出血流感染病原菌2320株,其中假丝酵母菌属148株占6.4%;无菌体液标本4093株,其中假丝酵母菌属253株占6.2%;侵袭性假丝酵母菌感染中ICU最高,值得重视;临床独立来源的82株白色假丝酵母菌,基于微卫星片段CAI区共有38种基因型,基因型18-26(9.76%)、16-21(8.54%)、21-21(7.32%)、11-18(4.88%)、18-18(4.88%)、11-20(4.88%)、25-33(4.88%)分布占优势;6例患者不同部位分离的白色假丝酵母菌基因型完全相同;体外药物敏感率氟康唑为93.2%、伏立康唑为94.5%、两性霉素B为100.0%、卡泊芬净为100.0%、5-氟胞嘧啶为97.3%。结论侵袭性白色假丝酵母菌仍然是主要病原菌,但非白色假丝酵母菌感染有不同程度的上升趋势,基因分型显示侵袭性白色假丝酵母菌呈多态性分布,发生侵袭的菌株基因型与定植的基因型有关。

Epidemiology trend and change of nosocomial invasive Candidainfections

OBJECTIVE To select the invasive Candida isolated from Chaoyang Hospital from 2000 to 2010 as the study objects and to explore the epidemiological trends and changes of invasive Candida infections.METHODS The invasive Candida were collected for data and statistics.The identification of the strains was performed by Chromagar agar with vitek 2 compact YST card,and 26S rDNA D1/D2-based single-strand conformation polymorphism(SSCP) patterns analysis of the molecular identification was applied to ensure the accurate molecular identification,and the genotyping of invasive C.albicans was performed by single-strand conformation polymorphisms(SSCP)of C.albicans’ microsatellite CAI combined with the GeneScan data.The MIC of 5 drugs were determined by ATB FUNGUS 3 system and E-test strip.RESULTS From 2000 to 2010,of totally 2320 strains of pathogens causing bloodstream infections isolated,there were 148(6.4%) invasive Candida strains;of totally 4093 strains isolated from sterile fluids,there were 253(6.2%) strains of invasive Candida detected;the invasive Candida infections were most common in ICU,which was worthy of attention;of 82 independent strains,38 distinct CAI genotypes were identified by GeneScan analysis,among which 18-26(9.76%),16-21(8.54%),21-21(7.32%),11-18(4.88%),18-18(4.88%),11-20(4.88%),and 25-33(4.88%)were dominant;the genotypes of C.albicans isolated from various parts of 6 patients showed exactly the same;In vitro antifungal susceptibilities testing indicated that the susceptibility rate to fluconazole was 93.2%,voriconazole 94.5%,amphotericin B 100.0%,5-fluorocytosine(97.3%),and caspofungin(100.0%).CONCLUSION Invasive C.albicans isolates remains the main pathogens,however non-C.albicans infections is increased in varying degrees.The genotyping shows that the invasive C.albicans is polymorphic,and the genotypes of C.albicans which result in invasiveness are associated with those of the colonized isolates.