Background Modifications in social habits together with the increase of emigration have contributed not only to increased dermatophytoses but also to an altered etiology. During the last few years, Braga has suffered a radical change from a rural to a cosmopolitan life-style.Methods A statistical study of dermatophytoses and the etiology of their causative agents was performed by a retrospective survey carried out among patients of Hospital de São Marcos, Braga, Portugal, from 1983-2002. In this study, a total of 10 003 patients were analyzed.Results Over this period the frequency of dermatophytoses, as defined by the recovery of a dermatophyte in culture, was found to be 23.6%, whereas nondermatophytic infections accounted for 7.0%. Analysis of the clinical forms and the isolated fungi supports that the dermatophyte species have a predilection for certain body areas ( P ≤ 0.01). Age is a very important factor regarding the occurrence of dermatophytoses ( P ≤ 0.0001), with a correlation between increasing age and infection, positive for Trichophyton rubrum and negative for Microsporum canis . Overall the gender of the patients is not an association factor for the development of dermatophytoses; however, significant differences were detected in the distribution of some etiologic agents ( P ≤ 0.05). ConclusionsThe results showed the main etiologic agent of dermatophytoses to be Trichophyton rubrum (37.4%). Moreover, dermatophytoses are both decreasing and showing a new profile in Braga, and a pronounced decrease of Trichophyton megninii was observed throughout the study.