Black Toenail Tale

In this presentation, a dermatologist recounts a case involving a 90-year-old man with bulbous black toenails, prompting concern from a primary care physician regarding potential necrosis or fungal infection. Upon examination, it was discovered that the black coloration was not due to fungi but rather a buildup from using the antifungal drug Cyclopyrox incorrectly. The caregiver had been applying the medication as instructed, but failing to properly allow it to dry before putting on black socks led to the discoloration. The dermatologist highlights how critical it is to assess nail conditions accurately, emphasizing the importance of distinguishing between exogenous factors such as trauma or improper care versus intrinsic pathological issues. Various types of nail dyschromia are discussed, including the causes of black nails ranging from subungual hemorrhage to surface staining, and how proper scraping or observation under a dermatoscope can reveal essential clues about the underlying condition. Ultimately, the presentation serves as a learning tool for healthcare professionals, underscoring the importance of careful examination and questioning in the evaluation of nail disorders.