Beyond the usual suspects: A case report of multi-etiological and multidrug-resistant Candida onychomycosis.

This is a rare case of Candida onychomycosis caused by three Candida species that were resistant to several antifungal drugs. A 56-year-old Iranian woman with no previous medical or injury history experienced discoloration and lifting of her left thumbnail for six months. Laboratory tests identified yeast and pseudohyphae consistent with Candida onychomycosis. Conventional and molecular techniques confirmed that onychomycosis was caused by three different Candida species. All strains were resistant to various antifungal drugs. Therapeutic failure, in addition to multi-drug resistance, may be due to the presence of multiple etiological agents.