Acquired Perforating Dermatoses

• Occurs in chronic renal failure and diabetes mellitus; in up to 10% of patients undergoing hemodialysis.
• Chronic pruritic condition triggered by trauma.
• Umbilicated papules with central hyperkeratotic crust (Fig. 18-4).
• Transepidermal elimination of collagen.
• Relationship with other perforating disorders not clear.