RESUMEN
Two separate studies were carried out to determine the dermatophytes responsible for tinea capitis in Puerto Rico. A retrospective study to determine those agents during the period between 1979 and 1989 revealed a total of 36 mycologically positive cases. The causative organisms consisted of the following species: M. canis, 14 cases (38.9 per cent ); T. mentagrophytes, 7 cases (19.4 per cent ); T. rubrum, 7 cases (19.4 per cent ); M. gypseum, 5 cases (13.9 per cent ); and T. tonsurans, T. verrucosum, unclassified Microsporum species, 1 case each (2.8 per cent each). In a prospective study, fungal cultures were obtained from the scalps of 95 randomly selected children (45 males, 50 females) seen at the outpatient dermatology clinics of the Medical Sciences Campus of the University of Puerto Rico for a variety of skin problems but with no symptoms or signs of disease. One culture was positive for M. canis. All other cultures were negative. The significance of these findings is discussed as well as their relation to the incidence of T. tonsurans scalp infections in the Unites States