Clinical evaluation of the NovaplexTM Dermatophyte qPCR assay for the detection of dermatophyte fungi and Candida albicans in skin and nail material.

Cutaneous fungal infections are usually caused by dermatophytes, but also yeasts and other non-dermatophyte molds. The microbiological diagnosis of these mycoses traditionally relies on direct microscopic examination (DME) and culture. However, these procedures hold important limitations. Recently, some marketed qPCR methods have emerged for the identification of both dermatophyte and non-dermatophyte fungi. Herein, we aim to perform a head-to-head evaluation of the clinical performance of the NovaplexTM Dermatophyte RUO qPCR assay (Seegene) in comparison to the EurobioPlex Dermatophytes CE-IVD-branded qPCR assay (Eurobio Scientific) for the detection of dermatophyte fungi in skin and nail material. Between February and July 2024, 998 samples (735 were nail material and 263 corresponded to skin specimens) from 945 patients were collected for the molecular investigation of dermatophyte fungi at the Navarra University Hospital in Pamplona, Spain. DNA extraction was performed following Seegene instructions, and both qPCR methods were subsequently executed. In case of discrepancies, the DermatoPlex qPCR assay (SpeeDx) was used, along with DME and culture results in some cases. Overall, the NovaplexTM Dermatophyte assay performed well for the molecular detection of dermatophyte fungi and Candida albicans in samples of skin and nails; with an overall agreement of 94.1 % when compared with the EurobioPlex Dermatophytes assay. Ignoring Microsporum spp. cases, only 59/998 (5.9 %) discrepancies were detected. Of them, most (62.7 %) evaluated the NovaplexTM Dermatophyte assay positively. Acknowledging the increased sensitivity of molecular methods compared to conventional procedures, the NovaplexTM Dermatophyte assay is a reliable qPCR method for diagnosis of cutaneous mycoses.