A 14-year old boy presented with approximately a 2-year history of progressive, asymptomatic hyperkeratosis of the elbows, hands, knees, and feet. He was generally in good health except for recurrent periodontal infections, which resulted in the loss of a tooth. His father and paternal grandmother also had similar findings. There was no known consanguinity in the patient’s family.
Physical examination revealed diffuse redness and hyperkeratosis of the palms, back of the hands (Figure 1), soles, and sides of the feet, with psoriasiform plaques on the elbows and knees. The patient also had evidence of periodontal inflammation and loss of the permanent left canine tooth of the lower jaw (Figure 2). A biopsy specimen was obtained from the hand (Figure 3).