RESUMO
BACKGROUND: Dermatophytoses are skin superficial mycoses in which clinical manifestations are directly related to the virulence of the infecting microorganism or the host immunity. CASE REPORT: We describe a severe case of dermatophytosis associated with exfoliative erythroderma, substantial palmoplantar keratoderma, onychodystrophy affecting all nails, diffuse non-scarring alopecia and tissue fungal invasion by Trichophyton tonsurans, which led us to the diagnosis of AIDS. Direct examination and culture for fungi from skin scraping from two different sites were performed. Biopsy and histopathological exam were also performed on three different sites. Direct examination of the lesions' scraping revealed septate hyaline hyphae and arthroconidia, identified as Trichophyton tonsurans by culture in glucose Sabouraud agar and Mycosel agar. A scalp biopsy revealed follicular fungal invasion and Majocchi's granuloma. Due to the severity of the presentation we requested an anti-HIV serology, which was positive. The patient was treated with itraconazole, 200mg/day, for 120 days, which promoted a complete regression of the lesions. CONCLUSIONS: Severe and atypical forms of dermatophytosis could lead to a diagnosis of AIDS.