[1, 4, 5] Sequencing of PCR products is a very powerful method for the correct typing of dermatophytes but, unfortunately,

it is not convenient for the processing large numbers of samples.[13, 14] Real-time PCR proved valuable in the identification of dermatophytes because of its high sensitivity and rapidity, but it is costly.[10, 11] This study aimed at evaluating a MX PCR technique based on the amplification of the CHSI gene and the ITS region which are the most widely used targets in the Alisertib molecular diagnosis of dermatophytic onychomycosis in humans.[8, 17, 21, 23] On the other hand, MX PCR was shown to be a powerful tool for the characterisation of dermatophytes when DNA extracted from clinical specimens is used.[1, 6, 7, 9, 17] We were only interested in T. rubrum and T. mentagrophytes complex because they are the most frequent among the species isolated in our region.[14, 23] In addition, previous reports on PCR assays that allow distinguishing TR and TM are very few.[9] In this study, MX PCR was applied to a collection of culture samples (standards and controls) of dermatophytes and non-dermatophytes fungi, and to nail specimens obtained from patients with dermatophytic onychomycosis previously confirmed by mycological examination. The analysis of our results showed that the specificity of the

technique was excellent as none of the non-dermatophytic fungal specimens and none of the uninfected nails yielded positive results in MX PCR. Our results Ulixertinib ic50 are in agreement with most previously studies.[4, 6, 7, 11, 16, 17, 25] As far as sensitivity is considered, MX PCR may be considered very satisfactory as 100% of controls and 97% of nail specimens yielded positive results. Sensitivity values reported in previous studies using different PCR methods and primers ranged between 51% and 94.8%.[1, 4, 6, 7, 11, 17, 19, 21] On the other hand, our results showed the PCR to be more sensitive than mycological examination (97% vs. 81.1%). This finding is in accordance with most previously reported studies.[5, 7, 9, 13, 19, 20, 25] In contrast, in some reports, results of PCR and mycological examination were nearly similar

in terms of sensitivity.[3, 12, 15] The threshold of DNA detection in MX PCR was 50 pg of DNA per reaction. This value is similar to that reported in Candida and Aspergillus almost systemic infections.[15, 16] In contrast, it is much higher than the threshold reported in MX PCR for the detection of other non-dermatophyte fungi.[19] The limited existing genomic data on dermatophytes and the close ITS gene sequence similarity between related dermatophyte species (e.g. T. rubrum and T. violaceum on one hand, and T. mentagrophytes, T. schoenleinii and T. tonsurans on the other hand) impede designing specific primers for all known dermatophyte species. Indeed, ITS region primer pair TR was found to cross-react with T. violaceum, and TM with T. tonsurans, T. equinum and T. schoenleinii.