Trichophyton mentagrophytes and Tinterdigitale genotypes are associated with particular geographic areas and clinical manifestations.

Abstract

The fungi Trichophyton mentagrophytes and Tinterdigitale account for significant amount of dermatophytosis cases worldwide. These two dermatophytes form a species complex and have a number of ribosomal internal transcribed spacer (ITS) region genotypes, allowing simultaneous species identification and strain typing. Our aim was to describe the geographic distribution of Tmentagrophytes/Tinterdigitale ITS region genotypes and find an association between the genotypes and clinical presentations of respective infections. We performed rDNA ITS region sequencing in 397 Iranian Tmentagrophytes/Tinterdigitale isolates and analysed all available in GenBank entries with sequences of this kind. For the study, 515 clinical annotations were available. Statistical analysis was performed by chi-squared test and Spearman rank correlation analysis. A total of 971 sequences belonged to genotypes with at least 10 geographic annotations and were classified on the basis of exclusive occurrence in a particular region or high relative contribution to a regional sample. We discerned Asian and Oceanian ("KU496915" Type V, "KT192500" Type VIII, "KU315316"), European ("FM986750" Type III, "MF926358" Type III*, "KT285210" Type VI) and cosmopolitan ("FM986691" Type I, "JX122216" Type II, "KP132819" Type II* and "AF170453" Type XXIV) genotypes. There was statistically significant difference in the ITS genotype distribution between different affected body sites. Trichophyton mentagrophytes "KT192500" Type VIII correlated with tinea cruris, Tmentagrophytes "KU496915" Type V correlated with tinea corporis, Tinterdigitale "JX122216" Type II correlated with tinea pedis and onychomycosis. Trichophyton mentagrophytes and Tinterdigitale genotypes can be associated with distinct geographic locations and particular clinical presentations.