Dermatophytosis among Filipinos: its incidence and flora in the outpatient dermatological clinic of the Philippine General Hospital

ABSTRACT

1. Mycologic laboratory studies consisting of KOH preparations for direct microscopic examination and cultural procedures for the isolation and identification of the causative pathogenic fungi were performed on 401 cases of suspected dermatophytosis in the Outpatient Skin Clinic of the Philippine General Hospital during the period August, 1948 to May, 19502. Ninety-one cases suspected of tinea pedis were studied. Twenty or 22% showed a positive KOH preparation for hyphal filaments. Eleven positive cultures were obtained, 10 of Trichophyton mentagrophytes and 1 of Trichophyton rubrum. This low figure of demonstration of the fungus is explained mainly by technical errors in the performance of the laboratory examination and the probable non-mycotic nature of a certain percentage of the cases3. Ninety-seven patients with involvement of the hands were seen and only one gave a positive KOH mount. Not a single culture showed growth of a dermatophyte4. Eighty-one cases with lesions on both feet and hands were examined. There were 15 cases with positive KOH of the feet and negative KOH of the hands. One case gave positive findings from both feet and hands. Only three positive cultures were obtained from the feet which proved to be Trichophyton mentagrophytes. None was isolated from the hand lesions5. There were 62 patients suspected of tinea corporis. Out of this total, 40 gave positive KOH mounts. Nineteen cultures were isolated, 13 of Trichophyton rubrum, 4 of Trichophyton mentagrophytes and one each of Trichophyton violaceum and Microsporum gypseum6. Fifty-six cases were diagnosed clinically as tinea cruris. Of these, 47 had a positive KOH mount. Twenty-two cultures were obtained with 19 of Trichophyton rubrum, 2 of Trichophyton mentagrophytes and one of Trichophyton violaceum. This preponderance of Trichophyton rubrum as the causative agent of tinea cruris in the series studied is in contrast to that recorded by most dermatologic textbooks which is Epidermophyton flocosum. The greater tendency of this form of tinea cruris caused by Trichophyton rubrum to spread to adjacent areas and to involve other sites was also observed7. The paucity of cases of tinea capitis, tinea unguium and tinea barbae in the clinical material studied is noted8. The results as obtained are compared with statistics reported by authors from other lands. (Summary)