[Dermatophytosis in a urban setting: prospective study of 135 cases].

During a period of one year all patients referred to the Dermatology department with the diagnosis of dermatophytosis were studied to determine the incidence. Etiology, and epidemiology of these infections in the northeast of Madrid. We have evaluated the sensitivity and specificity of the direct examination with 10% KOH with respect to the culture as well as the correlation between the clinical diagnosis and the result of the mycologic examination. The annual incidence was 8.4 cases per 10,000 inhabitants and the most frequent causal agents in a total number of 135 patients were Epidermophyton floccosum in 48 (35.5%), Microsporum canis in 36 (26.6%), Trichophyton mentagrophytes in 28 (20.7%) and Trichophyton rubrum in 12 (8.8%). In 5 patients there were simultaneous infection by two different agents. In a third part of the cases a previous contact with animals was reported. The direct examination had a specificity of 98% and a sensitivity of 83%. The diagnosis in the nonungual infections was confirmed in the 54% of the cases. The incidence of dermatophytosis in our geographical area is high. Due to the similarities with other diseases, the mycologic examination by microscopy or culture is essential.