Erythema Dyschromicum Perstans

Erythema dyschromicum perstans is an asymptomatic eruption of oval, polycyclic, or irregularly shaped, gray-blue hyperpigmented macules on the trunk, the arms, the face, and the neck. It begins as ash-colored macules, sometimes with an erythematous or elevated border. The patient is not usually suffer from any systemic symptoms. Erythema dyschromicum perstans may resolve in 2-3 years in prepubertal children, but it is more likely to persist in adults. [1] Erythema dyschromicum perstans (EDP) most often affects darker skinned patients, most frequently Latin Americans and Indians. It has also been reported in people of lighter skin colour and various ethnicities. It may occur in women more often than men. It is repoted in young adults than adults. The exact etiology of EDP is unknown. Damage to melanocytes and basal cell keratinocytes that is observed with EDP is due to an abnormal immune response to antigens with a predominance of CD8 + T lymphocytes in the dermis and HLA-DR +, intercellular adhesion molecule 1 + keratinocytes in the epidermis. EDP is characterized in histological examination by a vacuolar liquefactive degeneration of the basal cell layer with dermal melanosis and a perivascular infiltrate.