Erythema dyschromicum perstans.

A 29-year-old woman from Trinidad experienced the rapid onset of extensive lesions characteristic of erythema dyschromicum perstans following an x-ray study using orally administered contrast. Eleven months later a skin biopsy specimen showed few epidermal changes but extensive incontinence of melanin pigment and marked dilatation of lymphatics in the superficial dermis. Results of a systemic evaluation were normal. The available data on this disease are analyzed and conclusions offered regarding its nature and causes.