Acquired ichthyosis in uremic patients

Cutaneous xerosis is frequent in uremic patients, but its pathogenesis is still obscure. In this paper 140 uremic patients under regular dialysis have been investigated and followed for a period of 72 months to look for skin scaling and xerosis. 71 patients had ichthyosiform dermatosis. These were associated to follicular keratosis in all patients and in 28 of them there was also some degree of plantar keratosis. Light microscopy examination revealed a thickened, orthokeratotic stratum corneum and thin granular layer. On transmission electron microscopy desmosomal disks were retained up to the superficial part of the stratum corneum, and keratinosomes were increased at the margin of the horny layer and most of them lacked the typical lamelled inner structure and appeared vesicular. Moreover in several areas they showed an abnormal aggregation with the formation of cluster and small chains beneath the corneocytes. These findings would suggest that the so-called xerosis of uremia is a disorder of keratinization caused by a defect in the induction of desquamation.