Case study: pachyonychia congenita: a mixed type II-type IV presentation

A 52-year-old woman in good health with a family history negative for dermatologic diseases presented to our department with thickening and dystrophy of all her fingernails and toenails that started when she was born. She also had hyperkeratosis on the palms of her hands and soles of her feet that was confined to sites of pressure and recurrent plantar blisters that began appearing at puberty. The patient reported marked pain while walking from such plantar involvement. Her medical history revealed a persistent hoarseness; palmoplantar hyperhidrosis; and the appearance of numerous cysts on her back, neck, and scalp since she was 20 years old. These latter lesions had been diagnosed as multiple steatocystoma on the basis of the histologic features. Upon examination, all of her fingernails and toenails appeared shortened, thickened,and dystrophic (Figures 1-3). In addition, they presented subungual keratosis and a yellowish-gray color. Hyperkeratosis and small ulcerations were present on the perionychium. Palmoplantar keratoderma was evident, especially on the soles,in association with superficial erosions (Figure 4). Keratosis pilaris was evident on the extensor surfaces of the forearms as well as on the anterior surfaces of the legs. Multiple nodules were detected on the patient's neck, trunk, and axillary regions(Figure 5). They consisted of multiplex steatocystoma and were characterized by a hemispheric shape, a normal-appearing skin color, and by an elastic consistency on palpation. Oral and dental changes were not detected, although hair anomalies were evident. Laboratory parameters disclosed eosinophilia and increased total IgE levels. The results of serum protein electrophoresis was normal, as were those concerning hepatic and renal functions. The ophthalmology examination showed neither corneal dyskeratosis nor cataracts. The neurologic-psychiatric visit revealed slight mental retardation.