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Background: Dermatophytes are a group of keratinophilic fungi able to produce dermatophytosis or tinea infections. In Chile, Trichophyton rubrum and Trichophyton mentagrophytes are the ones most commonly isolated in adults, while Microsporum canis is found among children. Treatment of these infections is usually with topical or oral antifungals, such as griseofulvin or azole derivatives (clotrimazole, itraconazole, fluconazole), allylamines (terbinafine) or new drugs that are available., Aims: Evaluation of the in vitro susceptibility of dermatophytes to five antifungal agents and the comparison of the susceptibility pattern with that of previous years., Methods: Sixty-two clinical isolates of dermatophyte fungi were studied (March-June 2010). The CLSI M38-A2 micromethod was used., Results: Fluconazole MIC values for T. rubrum and T. mentagrophytes varied between 0.25 and 1 μg/ml; MIC range to clotrimazole, terbinafine and itraconazole was 0.03-0.06 μg/ml, and MIC values for griseofulvin were 0.015-0.03 μg/ml. No statistically significant differences were found between susceptibility patterns, except for fluconazole., Conclusions: Fluconazole was less active in comparison with other drugs tested (0.25-1 μg/ml). None of the isolates were resistant to any of the drugs, and no changes in the susceptibility pattern were observed when comparing the results with data previously reported concerning dermatophytes in Chile., (Copyright © 2013 Revista Iberoamericana de Micología. Published by Elsevier Espana. All rights reserved.)

Due to the pleomorphism and cultural variability displayed by species of the genus Trichophyton, the identification methods based solely on morphological features are usually insufficient for their classification. The goal of the present work was to test a set of phenotypic methods in order to identify fungal isolates that belong to the aforementioned genus. These methods were based on a molecular taxonomic technique used as standard. Clinical isolates (56) were used as samples along with 6 reference strains. Macro and micromorphological studies were performed as well as biochemical and physiological tests such as in vitro hair perforation, nutritional requirements in Trichophyton agar media, urease production and growth on bromocresol purple-milk. solids-glucose (BCP-MS-G) agar. Additionally, PCR fingerprinting using the (GACA)4 primer was employed. As a result of the PCR method, specific profiles were observed for Microsporum canis, Epidermophyton floccosum, Trichophyton rubrum and Trichophyton interdigitale. Identical profiles were obtained for Arthroderma benhamiae y Trichophyton erinacei. Of the total number of clinical isolates, 39 matched the T. rubrum profile while 13 corresponded to A. benhamiae and 4 to T. interdigitale. The most useful phenotypic test to differentiate between T. rubrum and T. mentagrophytes complex strains was alkalinization of the BCP-MS-G medium. Phenotypic tests did not allow differentiation among the T. mentagrophytes complex species. On the other hand, the molecular technique allowed characterization of T. rubrum isolates as well as of those observed in our study and included in the T. mentagrophytes complex: T. interdigitale and Trichophyton sp., the anamorph of A. benhamiae., (Copyright © 2013 Asociación Argentina de Microbiología. Publicado por Elsevier España. All rights reserved.)

Background: Dermatophytes can be divided into geophilic (soil), zoophilic (animals) and anthropophilic (humans) strains, depending on the source of the keratin that they use for nutritional purposes., Aims: The in vitro susceptibility of clinical isolates of dermatophyte fungi has been studied in the 3 ecological groups with several antifungal agents for the topical management of dermatophytoses in order to determine their relationship with the ecological group., Methods: A standardised dilution micromethod in a liquid medium was used for the determination of the in vitro antifungal activity of 9 topical antifungal drugs: amorolfine (AMR), bifonazole (BFZ), clotrimazole, econazole, ketoconazole, miconazole, oxiconazole, terbinafine (TRB) and tioconazole. The in vitro activity was obtained against 124 clinical isolates of dermatophyte moulds from the anthropophilic, zoophilic and geophilic ecological groups., Results: The in vitro antifungal activity was different depending on the ecological group, although a species-dependent profile was also observed., Conclusions: Azole derivatives showed a similar antifungal profile, being more active against anthropophilic dermatophytes > zoophilic > geophilic. Activity of TRB and AMR was different from that of azole derivatives (zoophilic > anthropophilic > geophilic). A higher in vitro antifungal activity against the 3 ecological groups was observed with TRB and AMR, whilst BFZ was the less active drug., (Copyright © 2012 Revista Iberoamericana de Micología. Published by Elsevier Espana. All rights reserved.)

Although Trichophyton raubitschekii was first described by Kane et al. as a distinct species of dermatophyte, it is now classified as a variety of T. rubrum. The variety raubitschekii differs from the other varieties of T. rubrum in morphology, physiology, epidemiology and patterns of infection, but they are indistinguishable using molecular methods. T. rubrum var. raubitschekii is mostly found in Africa, Asia and South America. We present two cases of imported mycosis in two Nigerian men due to T. rubrum var. raubitschekii. The patients have Tinea cruris lesions on the buttocks. These are the first reported cases of this dermatophytosis in Spain.

Population changes taking place in recent years, such as more frequent travel to endemic areas, immigration, and international adoptions, have all contributed to a resurgence of certain pathogens in our geographical area. This is the case of Trichophyton violaceum. A retrospective review was made of all cases of superficial mycosis caused by T. violaceum in patients receiving in-hospital treatment during the years 2000 to 2006. This microorganism accounted for 18.5% of the 275 dermatophytes isolated during the above-mentioned period. In 96% of T. violaceum infections, the lesion manifested as tinea capitis, and all the patients were foreigners. We report in increase of tinea capitis caused by T. violaceum among pediatric patients that appears to be directly related to immigration.

Five cases of tinea corporis in children by Microsporum gypseum are presented. In four of them an endothrix type of parasitism with arthrospores 4 to 8 microns in diameter was observed. In the other case ectothrix and endothrix types of parasitism were seen in different hairs. Endothrix infection of hairs by species of the genus Microsporum has not been clearly demonstrated until the present. Three isolates were identified as Nannazzia gypsea of the "+" mating type.