Araujo R, Pina-Vaz C, Rodrigues A G, Amorim A, Gusmão L
IPATIMUP, Institute of Pathology and Molecular Immunology, University of Porto, Porto, Portugal.
Clin Microbiol Infect. 2009 Mar;15(3):260-6. doi: 10.1111/j.1469-0691.2008.02661.x. Epub 2009 Jan 22.
The answers to important questions concerning Aspergillus fumigatus pathogenicity, transmissions routes and efficacy of treatments require highly discriminating and reproducible genotyping methods. The present study was aimed at improving microsatellite methodology for A. fumigatus typing by reducing the task of strain identification to a single multiplex reaction and by selecting highly accurate short tandem repeat polymorphisms. A set of eight primer pairs was used for the genotype determination of 116 clinical isolates of A. fumigatus obtained from three healthcare centres. A new, automated and highly discriminatory typing method is described for A. fumigatus strains. The optimized multiplex PCR was successfully performed with all tested clinical strains and showed a discriminatory power of 0.9997 among presumably unrelated isolates. The comparison of groups of strains from different health centres showed that 99.6% of the genotypic variation was present within groups. Strains with the same genotype were isolated from the same patient, sometimes recovered more than 1 year later. A few cases of patients at the same clinic unit carrying strains of identical genotype strongly suggested colonization by A. fumigatus during their hospitalization. Specific measures must therefore be taken in order to prevent and restrict such incidents.
关于烟曲霉致病性、传播途径及治疗效果等重要问题的答案，需要高度区分且可重复的基因分型方法。本研究旨在改进烟曲霉分型的微卫星方法，将菌株鉴定任务简化为单一多重反应，并选择高度准确的短串联重复多态性。一组八个引物对用于对从三个医疗中心获得的116株烟曲霉临床分离株进行基因分型。本文描述了一种针对烟曲霉菌株的新型、自动化且高度区分性的分型方法。优化后的多重PCR在所有测试临床菌株中均成功进行，在可能不相关的分离株中显示出0.9997的区分能力。对来自不同医疗中心的菌株组进行比较表明，99.6%的基因型变异存在于组内。从同一患者分离出具有相同基因型的菌株，有时在一年多后仍能再次分离到。同一临床科室的少数患者携带相同基因型菌株的病例强烈提示他们在住院期间被烟曲霉定植。因此，必须采取具体措施以预防和限制此类事件。
