Onychomycosis: rationalization of topical treatment.

BACKGROUND: Fungal infection of the nail affects millions of people worldwide and has an estimated prevalence of more than 10% of the general population.

OBJECTIVES: To determinate the prevalence of fungal infection in toenails, in order to decide the treatment policy for onychomycosis.

METHODS: We evaluated 331 patients with suspected clinical toenail onychomycosis affecting at least two toenails. Mycological examination of the affected nails was performed; both the KOH test and fungal culture were used.

RESULTS: Of 331 patients with suspected clinical toenail onychomycosis, 78.2% of the patients had at least three infected nails. The first toenail was the most affected. Trichophyton rubrum was by far the most common dermatophyte cultured from all samples.

CONCLUSIONS: Most of the patients had at least three affected toenails. Topical treatment is not effective or practical, and systemic treatment should therefore be considered.