Hoof nail deformity: a previously unknown hereditary nail malformation

Abstract

Funding sources: none. Conflicts of interest: none declared. Dear Editor, A 54‐year‐old man who was followed by dermatology regarding a personal history of malignant melanoma was found to have an incidental nail abnormality affecting his bilateral second toenails. The malformed nails had been present since birth, were nonprogressive and were not associated with any symptoms. The patient denied any history of hair, teeth or sweating abnormalities. The patient also had a history of porphyria cutanea tarda, hepatitis C acquired via a blood transfusion, diabetes mellitus type 2 and a 40 pack‐year smoking history. His medications included metformin and sitagliptin. Interestingly, the patient was aware that his nail deformity was a family trait as many of his relatives had a similar alteration dating back to his father, which they kiddingly referred to as the ‘family surname, toe’. He was a child of a nonconsanguineous marriage and had eight siblings, with the patient himself being the sixth eldest (Fig. 1). Over four generations, six members of the family, including the patient himself, appeared to have had the same nail abnormality of varying severity affecting the same digits. Specifically, his father and two of his three daughters were afflicted with malformed bilateral second toenails (Fig. 1). No other family members had a history of melanoma, diabetes or porphyria.