Onychomycosis represents one of the most frequent mycoses in the world. Causative agents are mainly dermatophytes, but yeasts and nondermatophyte moulds can also be involved. Conventional diagnostic methods include direct microscopy (or histology) and culturing. However, molecular methods are becoming increasingly popular in this field. The DermaGenius® (DG) Nail multiplex assay (PathoNostics, The Netherlands) is a new commercial real-time polymerase chain reaction (PCR) kit, which can detect Trichophyton rubrum, Trichophyton interdigitale and Candida albicans directly in nails. The present study is a retrospective evaluation of the kit applied to 138 finger and toenail clippings in comparison to histology and culture methods. The sensitivity and specificity of the PCR assay are 80% (76/95) and 74.4% (32/43), respectively, when histology and culture are used as reference to define onychomycosis. DG performance is not different from histology combined with culture (P = .11) but the best diagnostic efficacy (88.4%, 122/138) is obtained by the combination of histology and DG. In conclusion, this study emphasizes the clinical usefulness of the DG in diagnostics. The high specificity of this test guarantees a better identification compared to culture that can lead to dermatophyte misidentifications. It is a reliable PCR assay that shortens the time to diagnosis and can unmask the presence of nongrowing fungal pathogens in nails.

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For the successful treatment of dermatophytoses, especially tinea capitis, there is a need for accurate and rapid diagnostic methods. A lot of recent literature has focused on the detection of dermatophytes directly on sample material such as nails, hair and skin scrapings. Molecular tools offer the ability to rapidly diagnose dermatophytosis within 48 h. This study aimed to compare the results of a commercial real-time PCR (real-time PCR) assay DermaGenius®(DG) 2.0 complete multiplex kit with those of conventional diagnostic methods (direct microscopy and culture). A total of 129 hair samples were collected in Dakar (Senegal) from patients suspected of dermatophytosis. DG was applied for the molecular detection of Candida albicans, Trichophyton rubrum/soudanense, T. interdigitale, T. tonsurans, T. mentagrophytes, T. violaceum, Microsporum canis, M. audouinii, Epidermophyton floccosum, T. benhamiae and T. verrucosum. Dermatophytes species and C. albicans were differentiated by melting curve analysis. The sensitivity and specificity of the PCR assay were 89.3% and 75.3%, respectively. DG PCR was significantly more sensitive than culture (p < 0.001). DG PCR is fast and robust to contamination. In this paper, the main questions discussed were the replacement of culture by a broad-spectrum fungal real-time PCR and the implementation of DG PCR into a routine laboratory in Senegal.

During recent years the proportion of tinea capitis infections due to Microsporum audouinii has increased in both Belgium and other European countries. To better understand the emergence of this species, the Belgian National Reference Centre for dermatophytes launched an epidemiological survey on the main anthropophilic dermatophytes causing tinea capitis in Belgium and included the genomic characterization of M. audouinii isolates. In total, 116 strains of M. audouinii were confirmed and characterized by the DiversiLab(®) system (bioMérieux). Six genotypic variants were identified, among which one major group included 90 isolates and the reference strain. Another variant group (11 strains) was exclusively confined to a geographical region in south Belgium. Analysis of epidemiological characteristics of the infected population showed that the main age category was 5- to 9-year-old children with a sex ratio (male/female) of 1.97. Data concerning the geographic origin of the family revealed a majority of Belgian nationality (44.7%), suggesting that the infection originated in Belgium. Other nationalities were primarily African. At this time, no clear correlation has been established between one particular strain and a specific country of origin.

Objectives We first compare the efficiency of mould/dermatophyte identification by MALDI‐TOF MS using a new medium called Id‐Fungi plates (IDFP) from Conidia® and two different databases. For the second purpose, we evaluated a new version of the medium supplemented with cycloheximide, Id‐Fungi plates Plus (IDFPC) for the direct inoculation of nails, hair and skin samples and compared the efficiency of MALDI‐TOF MS identification of dermatophytes to classical methods based on culture and microscopy. Methods A total of 71 strains have been cultured IDFP and Sabouraud gentamicin plates (SGC2) and were identified by MALDI‐TOF MS. For the evaluation of the combination IDFPC/ MALDI‐TOF MS as a method of identification for dermatophytes, 428 samples of hair nails and skin were cultivated in parallel on IDFPC and Sabouraud + cycloheximide medium (SAB‐ACTI). Results For Aspergillus sp and non‐Aspergillus moulds, the best performances were obtained on IDFP after maximum 48‐h growth, following protein extraction. For dermatophytes, the best condition was using the IDFP at 72 hours, after extended direct deposit. Regarding the direct inoculation of nails, hair skin on IDFPC, 129/428 (30.1%) showed a positive culture against 150/428 (35%) on SAB‐ACTI medium. Among the 129 positive strains, the identification by MALDI‐TOF MS was correct for 92/129 (71.4%). Conclusion The IDFP allows the generation of better spectra by MALDI‐TOF MS compared to SGC2. It facilitates sampling and deposit. Regarding the use of IDFPC, this medium seems less sensitive than SAB‐ACTI but among positive strains, the rate of correct identification by MALDI‐TOF MS is satisfactory.