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A46-year-old man presented with a pruritic diffuse erup-tion on his thighs, lower legs and buttocks that had grad-ually worsened over a 1-year period. His medical his-tory included a heart transplant, insulin-dependent diabetes mellitus, chronic renal failure for which he was receiving peri-toneal dialysis, hypertension, gout and hyperlipidemia. An exam-ination showed follicular keratotic papules that were distributed diffusely over his legs and buttocks (Figure 1). The results of a skin biopsy showed a hair follicle with perforation that extended into the dermal tissue and contained a tract of necrotic tissue debris with degenerate elastin fibres (Figure 1). These findings were consistent with acquired perforating dermatosis. Perforating dermatoses are a group of conditions character-ized by transepidermal elimination of dermal material (colla-gen, elastic tissue or necrotic connective tissue). Major perfor-ating disorders include reactive perforating collagenosis (inherited disorder of collagen perforation), elastosis perforan