"I forgot to shave my hands": A case of spiny keratoderma.

A 57-year-old Caucasian man presented with multiple asymptomatic spiny papules on the palms and soles that he had been shaving off with a razor for many years. He was otherwise healthy with no personal or family history of skin disease or malignancy. A diagnosis of spiny keratoderma of the palms and soles or "music box spine dermatosis" was made. The clinical, histologic, and electron-microscopic features of spiny keratoderma are distinct. This entity previously had multiple classifications and it is important to distinguish it from other keratodermas as some keratodermas can be linked to cutaneous and internal malignancies and conditions: polycystic kidney disease, liver cysts, Darier's disease, and hyperlipoproteinemia among others. Spiny keratodermas can have systemic associations and do not resolve spontaneously. Treatment is generally ineffective.