A Study On Transmission Route Of Tinea Cruris

Background:Tinea cruris is an intensely pruritic dermatophyte infection of the groin and adjacent skin, tending to recurrent and reinfect, which may threaten people’s physical and mental health seriously. There is an idea that superficial mycoses can be a source of infection for tinea cruris, but the studies on the level of molecular biology are rarely seen. So to investigate the sources of infection and transmission route of tinea cruris, analyzing the genomic homologies of pathogenic organism which isolated from the patients with tinea cruris and who also suffered other superficial mycoses is of significance.Objective:Using high-resolution melting analysis (HRM) to evaluate the genomic homologies of dermatophyte isolated from the lesions of tinea cruris and other superficial mycoses. It is helpful to identify the infecton source and transmission route for tinea cruris, and to provide evidence for elucidating its mechanism of recurrence, molecular epidemic survey and the prevention.Methods:1. Suspected tinea cruris patients were all recruited into the survey from January2012to December2012in Dermatology department of Lanzhou University Second Hospital. Relevant informations of patients and diseases were recorded in details by questionnaires and observation. Specimens were isolated from the two sites of tinea cruris and other superficial mycoses, and collected for direct microscopical examination and cultivation. Positive samples were detected by cultural and morphological characteristics on Sabouraud’s dextrose agar, Christensen urea agar, potato dextrose agar, and mini-cultivation.2. Randomly amplified polymorphic DNA (RAPD) and high-resolution melting analysis (HRM) were used if the strains isolated from different sites were same in species.Results:1. Thirty-nine cases of tinea cruris were collected. Of these,30cases were suffered from other superficial mycoses simultaneously. Pathogenic fungi isolated from different parts of23patients with tinea cruris and other superficial mycoses were same in species,58.97%of total cases (21patients with tinea pedis,53.84%of total cases;1patient with both onychomycosis and tinea pedis,2.56%of total cases;1patients with onychomycosis,2.56%of total cases), pathogenic fungi isolated from7cases were different,17.94%of total cases. 2. Using HRM analyzing the tandem repeat subelements TRS-1, located in the T. rubrum, three genotypes come out, the curves of23cases from different parts are same, of3cases are different, which associated with the electrophoresis demonstrated that using HRM to assess the genomic homologies of T. rubrum is reliable and accurate.Conclusions:1.Endogenous propagation route is the main transmission route of tinea cruris,58.97%of total cases.2. Tinea pedis and onychomycosis are important infection sources for tinea cruris, and tinea pedis is more closely related with tinea cruris.