HPI: This otherwise healthy 70 yo woman was seen for lichen simplex chronicus of the dorsum of the feet. An incidental finding was that of black toe nails. Anamnesis reveals that this has been present for greater than ten years. She is was on no meds by mouth when this developed.
O/E: Most of her toe-nails are black. One or two have longitudinal melanocytic striae. Her finger nails are normal. The toe nails are thickened with subungual hyperkeratosis.
Diagnosis: Melanonychia. Is this a dermatophyte, a yeast or a saprophyte? We will wait to see what culture shows. What are your thoughts?
A case of melanonychia due to Candida albicans
Abstract: Melanonychia is characterized by tan, brown, or black pigmentation within the nail plate. Fungal melanonychia is rare and may simulate longitudinal melanonychia caused by melanocytic lesions. We report six cases of fungal melanonychia which were confirmed histopathologically or mycologically. On culture, Candida and/or Aspergillus species were isolated in four patients. The nail pigmentation improved after treatment with antifungal agents in all cases, but one patient experienced a new lesion on another nail after cessation of treatment. Fungal infection should be considered as a cause of melanonychia, and fungal melanonychia should be differentiated from the melanonychia caused by melanocytic lesions, particularly by subungual melanoma.