Internal validation of GPS™ MONODOSE CanAur dtec-qPCR kit following the UNE/EN ISO/IEC 17025:2005 for detection of the emerging yeast Candida auris

Abstract

Candida auris is an emerging multidrug resistant pathogenic fungus that causes candidaemia with high mortality rates and exhibits the ability to persist within the hospital environment. Candida auris is phylogenetically closely related to Candida haemulonii, C. lusitaniae, C. pseudohaemulonii and C. duobushaemulonii and is frequently misidentified by commercial identification methods. In the present study, the GPS™ MONODOSE dtec-qPCR kit (dried single-dose PCR tubes) for the detection of C. auris was validated following the guidelines of the UNE/EN ISO/IEC 17025:2005, the French Standard NF T90-471:2010 and using fast-cycling protocols. Validation terms included in vitro specificity (inclusivity/exclusivity), quantitative phase analysis (10-106 standard DNA copies), reliability (repeatability/reproducibility) and sensitivity (detection/quantification limits). GPS™ dtec-qPCR kits passed validation with strict acceptance criteria (n ≥ 10 repetitions). In silico specificity was proven by the designer (GPS™). Experimental inclusiveness was achieved in two independent laboratories by testing strain JCM15448T and 117 clinical C. auris isolates from Asia, the Middle-East Africa, Latin America and Europe. Exclusiveness was evaluated with 25 strains of closely related Candida spp. Use of the MONODOSE format provided considerable advantages allowing the detection of C. auris to be accurately achieved in less than an hour. The GPS™ MONODOSE dtec-qPCR kit is ready to undergo clinical evaluation.