YST鉴定卡与焦磷酸测序鉴定酵母样真菌的应用评价

摘要

Objective To evaluate the ability of Vitek 2 Compact YST identification cards and pyrosequencing analysis for identifying the clinical isolates of yeast-like fungi.Methods Vitek 2 Compact YST identification cams and ITS1 region pyrosequencing analysis were used to identify the clinical isolates of yeast-like fungi at Jinan Military General Hospital in 2011.The strains which could not be identified to species by pyrosequencing analysis were identified again by the method of ITS1 region Sanger sequencing.The strains with inconsistent identified results by YST and pyrosequencing were identified again using API 20C.Results A total of 282 srtains were isolated from various clinical specimens for culturing in 2011.In addition to the three which could only be identified to similar species,other strains could be clearly identified to species by the method of ITS1 reverse pyrosequencing.Three strains which failed identified to species by pyrosequencing couldn't be distinguished fully by the method of Sanger sequencing.There were 7 strains unidentified,14 strains low discrimination(％ id ＜ 80％),and 6 strains misidentification using YST cams.The identification coincidence rate was 90.4％.The identification coincidence rates were various in different species of yeast-like fungi using YST cards.Conclusions The vast majority of clinical isolates of yeast-like fungi could be identified by ITS1 reverse pyrosequencing analysis.Vitek 2 Compact YST caRD basically meets the needs.But attention should be paid to the standard operating and regular internal quality control.For some rare species it is also needed to combine the source of specimen,colonies and characteristics to determine the identification results for the rare stains.%目的 评价Vitek2 Compact YST鉴定卡与焦磷酸测序分析鉴定临床分离酵母样真菌的能力.方法 采用Vitek2 Compact YST鉴定卡和焦磷酸ITS1区测序分析回顾鉴定了2011年度济南军区总医院临床分离的酵母样真菌.焦磷酸测序法不能鉴定到种的菌株用Sanger法ITS1区测序复核.YST与焦磷酸测序鉴定结果不一致的菌株用API 20C复核.结果 分离自本院2011年临床送检的各类微生物培养标本的酵母样真菌共282株.ITS1区反向焦磷酸测序分析除3株只能鉴定到相似菌种外,其余菌株均能明确鉴定到种,且与其代表参照序列的同源性均为100％.焦磷酸测序法未能鉴定到种的3株菌,Sanger法测序分析仍然不能完全区分.YST卡未能鉴定的有7株,低分辨率(即鉴定百分率＜80％)的有14株,另有6株鉴定错误,鉴定符合率为90.4％,不同种类的酵母样真菌YST卡的鉴定符合率不同.结论 焦磷酸测序法ITS1区反向测序分析能够完成绝大多数临床分离酵母样真菌的菌种鉴定;Vitek 2 Compact YST卡鉴定基本满足了临床工作需要,但要注意规范标准操作,定期进行室内质控.对一些少见菌种还需结合其分离部位、菌落及菌体特点等综合判断其鉴定结果正确与否.