Candida ciferrii: clinical and microbiological features of an emerging pathogen.

The authors report six cases of toenail onyxis due to an unusual yeast species, Candida ciferrii. For half of these cases, direct microscopical examination showed the presence of blastospores and pseudo-to-true mycelium, demonstrating the parasitic transition of the fungus. In light of the literature and of their own experience, the authors suggest that C. ciferrii could be an etiological agent of onychomycosis, particularly for elderly patients with extensive trophic disorders.