| An isolated focal, hereditary palmoplantar keratoderma with characteristics of linear hyperkeratosis along the flexor aspect of the fingers and on palms, as well as focal hyperkeratosis of the plantar skin. Patients present with painful thickening of the skin on palms and soles with occasional fissuring, blistering and hyperhidrosis. Rarely, hyperkeratosis on other areas may be seen (knees, dorsal aspects of the digits). Histopathologically widened intercellular spaces between keratinocytes are observed. |