Resumo (EN)
Objective – Describe the nature of the causal agent of onychomycosis, as well as analyze the distribution of cases of onychomycosis according to patient demographics and the main etiological agents. Methods – Based on an inductive and deductive where by conducting a descriptive study methodology was possible to survey data on mycology (conducted from April 2006 to October 2012) contained in records belonging to the database of the Laboratory of Microbiology, Faculty of Medicine of São José do Rio Preto, SP. Results – Five hundred eight-nine mycological exams were performed, 72% (426/589) were positive for laboratory diagnosis of onychomycosis. 77%of patients with onychomycosis were women. The most affected age group was between 36 and 60 years. The yeast Candida parapsilosis and filamentous fungus Trichophyton rubrum were the main causative agents of onychomycosis. Conclusion – The knowledge of the etiology of onychomycosis provided by this study, in the region of São José do Rio Preto will be measures to control this infection, reducing relapses and treatment optimization.