Fungal and bacterial strains used in this study.

Background
Filamentous fungi of the genus Madurella are the primary causative agents of mycetoma, a disease observed in tropical and subtropical regions. Since early diagnostics based on a morphological approach are difficult and have many shortcomings, a molecular diagnostic method suitable for rural settings is required. In this study, we developed the loop-mediated isothermal amplification (LAMP) method to present a foundational technique of the diagnosis of Madurella spp. (M. mycetomatis, M. pseudomycetomatis, M. tropicana, and M. fahalii), the common causative organisms of eumycetoma.
Principal findings
We successfully designed a primer pair targeting the rDNAs of three Madurella spp. excluding M. fahalii, and detected up to 100 fg of genomic DNA extracted from isolates of M. mycetomatis and 1 pg of M. pseudomycetomatis and M. tropicana, within one hour. Second, a primer pair specific to M. mycetomatis, the most common causative species, or M. fahalii, a drug-resistant species, was constructed, and the detection limit of both primer pairs was 1 pg. The designed primers accurately distinguished 16 strains of the genus Madurella from various fungal species known to cause mycetomas.
Conclusion
In summary, we established the first model of a LAMP detection method that rapidly and sensitively detects and identifies Madurella isolates for clinical diagnostics. Moreover, the combined designed primer sets could identify mycetoma-causing strains simultaneously.

背景
马杜拉霉属（Madurella）丝状真菌是真菌性足菌肿（eumycetoma）的主要致病菌，该病主要流行于热带及亚热带地区。由于基于形态学的早期诊断方法难度大且存在诸多缺陷，亟需一种适用于基层乡村医疗卫生场景的分子诊断方法。本研究开发了环介导等温扩增（loop-mediated isothermal amplification, LAMP）技术，作为针对该疾病常见致病病原体——马杜拉霉属菌种（包含马杜拉马杜拉霉M. mycetomatis、假马杜拉马杜拉霉M. pseudomycetomatis、热带马杜拉霉M. tropicana以及法哈勒马杜拉霉M. fahalii）的临床诊断基础性技术手段。
主要研究结果
其一，我们成功设计了靶向除法哈勒马杜拉霉外的3种马杜拉霉属菌种核糖体DNA（rDNAs）的引物对，可在1小时内检出马杜拉马杜拉霉分离株的基因组DNA最低量达100 fg，假马杜拉马杜拉霉与热带马杜拉霉的检出限则为1 pg。其二，我们构建了针对最常见致病菌种马杜拉马杜拉霉，或是耐药菌种法哈勒马杜拉霉的特异性引物对，两组引物的检出限均为1 pg。所设计的引物可准确将16株马杜拉霉属分离株与其他已知可引发足菌肿的真菌区分开来。
结论
综上，本研究建立了首个环介导等温扩增检测方法模型，可快速、灵敏地检测并鉴定用于临床诊断的马杜拉霉属分离株。此外，组合使用所设计的引物组可同时鉴定致病真菌性足菌肿菌株。