This 65-year-old woman had a history of incontinentia pigmenti with the typical evolution of skin lesions in early infancy. In her 20's she began to develop painful subungual nodules which were thought to represent warts and were relieved only with surgical destruction. None of the tumors resolved without treatment and many slowly enlarged. A subsequent biopsy was interpreted as a squamous cell carcinoma, and her right index finger was amputated. Recent biopsies from her nail bed demonstrated changes consistent with the subungual dyskeratotic tumors reported in incontinentia pigmenti. She was treated with a daily 25 mg dose of acitretin for 2 months with clearing of the tumors and symptoms.Painful subungal dyskeratotic tumors are one of the late manifestations of incontinentia pigmenti (STIP), appearing after puberty from age 15 to 31 years. STIPs are more frequent on the fingers than on the toes. They tend to destroy the distal phalanx by pressure necrosis of the underlying bone, and they displace the nail from the nail bed, causing nail dystrophy. Partial onycholysis often precedes the appearance of keratotic crusted papules and nodules at the distal nail bed. Pain is initially intermittent, but increases in intensity and duration as the tumor enlarges. In the proximal subungal tissue, the tumors may produce a paronychia-like lesion. Drainage of firm keratinaceous plugs or purulent debris secondary to bacterial infection may be present.
multiple dystrophic nails with subungual nodules and onycholysis and splitting of nails