POROKERATOSIS

Abstract

POROKERATOSIS is an unusual chronic progressive keratoatrophoderma, persisting throughout life and characterized by circinate or oval plaques with an annular hyperkeratotic linear elevation at the border, which progresses peripherally leaving a certain amount of atrophy at the center. There is often a dike or slender furrow running along the summit of the border, from which arises a keratotic ridge.¹ Mibelli, in October 1893, reported 3 cases of a previously undescribed disease which he named porokeratosis after histologic examination, on the ground that the most important anatomic lesion consisted of hyperkeratosis of the sweat duct and sweat pore.² One case described by him had been first observed by Majocchi in 1887. The true nature of the disease in this case had not been recognized, and it had been presented as a case of "ichthyosis hystrix." When Mibelli saw the patient he recognized the lesions as exceptional and different from