Abstrakt
During two-year molecular-epidemiological study focused on the non-Trichophyton rubrum dermatophytes in the Czech Republic, two species with unusual morphology were isolated from Czech patients. These species showed unique fingerprinting pattern (M13-core primer) and sequence data (ITS rDNA, beta-tubulin and RPB2 gene).
The combination of macro- and micromorphological, physiological and phylogenetic data collected in this study justified that both isolates represented undescribed species. The Trichophyton isolate was associated with a case of probable distal lateral subungual onychomycosis affecting the right great toenail of a 33-year-old man.
However, the pathogenic role of this isolate was not confirmed by two consecutive nail samplings and also the direct microscopical examination of nail scrapings was negative. This species probably belonged to the geophilic dermatophytes based on phylogenetic analysis and was most closely related to the anamorphic T. thuringiense, homothallic Arthroderma ciferrii (anamorph T. georgiae) and heterothallic A. melis.
The species is characterized by yellowish colonies, red reverse on several media, positive urease test, negative hair-perforation test, absence of growth at 34 oC, absence of macroconidia, formation of one-celled clavate microconidia, spiral hyphae and sterile gymnothecium- like structures covered by peridial hyphae. The Microsporum isolate was associated with a case of tinea corporis in a 45-year-old female.
The skin lesion was located at the dorsal right wrist and at first consisted of three 6 mm wide lesions which later merged to form a single circular lesion having a diameter of 40 mm. Direct microscopic examination of epithelial scales revealed the presence of septate, branching hyphae suggestive of dermatophyte infection and the same species grew on all slants in pure culture.