What is transepidermal elimination? What is its relationship to kidney disease?


Perforating disease of chronic renal failure. A, Small erythematous papules with central crusts or scales are seen on the lower legs. Central umbilication of the papules can be seen, the area of 'perforation.' The hyperpigmented macules are areas of prior involvement. B, Close-up of hyperkeratotic papule demonstrating cell area of perforation. (Courtesy of James E. Fitzpatrick, MD.)
Fig. 38.2 Perforating disease of chronic renal failure. A, Small erythematous papules with central crusts or scales are seen on the lower legs. Central umbilication of the papules can be seen, the area of 'perforation.' The hyperpigmented macules are areas of prior involvement. B, Close-up of hyperkeratotic papule demonstrating cell area of perforation. (Courtesy of James E. Fitzpatrick, MD.)
These are a group of diseases in which altered components of skin are eliminated via the epidermis, a process termed transepidermal elimination. Several different perforating diseases have been associated with chronic renal failure, including Kyrle’s disease, reactive perforating collagenosis, and perforating folliculitis. Because features of more than one type of perforating disorder have been noted in skin biopsies from patients with chronic renal failure, it has been suggested that this condition be referred to as the acquired perforating dermatosis of chronic renal failure. This eruption occurs in up to 10% of patients on dialysis but has also developed in patients with renal failure even without dialysis treatment. The lesions consist of keratotic papules and nodules on the trunk and extremities (Fig. 38-2). They occur more commonly in black patients. Skin biopsy confirms the diagnosis. Recently, treatment with narrow band ultraviolet B radiation has been reported to be effective in the treatment of this condition. This eruption may resolve spontaneously over a period of months.

Ohe S, Danno K, Sasaki H, et al: Treatment of acquired perforating dermatosis with narrowband UVB, J Am Acad Dermatol 50:892– 894, 2004.

Patterson JW: The perforating disorders, J Am Acad Dermatol 10:561–581, 1984.