The mother of an 8-year-old boy came seeking treatment for “a family ailment.” Both mother and child had bilateral, symmetric, confluent hyperkeratotic plaques with a smooth, waxy surface on the palmar and plantar surfaces. The hyperkeratotic area was outlined with sharply demarcated pinkish bands. Tactile sensations were intact. There were no defects in dentition, scalp hair, or nails. The mother noted that half of her relatives as well as her 6-month-old daughter also had thickened palms and soles.

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