Pachyonychia congenita Jackson-Lawler type: a distinct malformation syndrome

A family with three members in two generations affected by pachyonychia congenita, hyperkeratosis and hyperhidrosis of the palms and soles, follicular keratosis, neonatal teeth and epidermoid cysts (Jackson-Lawler syndrome) is described. The nosological autonomy of this condition is proposed and a further heterogeneity is suggested on the basis of histopathological changes in the subcutaneous cysts.