Usually, long-term treatment for Wilson disease provokes the occasional case of EPS, but its use in the treatment of cystinuria and rheumatoid arthritis has had similar effects. The EPS eruption may appear 1 or more years after the start of treatment. This eruption often is symmetrical, widespread, and long lasting. It may appear at any time after treatment begins and usually resolves after withdrawal of the drug. Clinical features of EPS Primary lesions are eruptive, dome-shaped, eventually umbilicated papules, measuring a few to several millimeters in diameter.
Lesions are flesh colored to red.
Usually, lesions are grouped in linear, arciform, circular, or serpiginous patterns, measuring several centimeters in diameter. New papules may appear in lines and figures that appear to migrate and enlarge peripherally. Any part of the skin may be affected. Most patients have only 1 area of skin involvement at a time, with the exception of Down syndrome patients, who typically have numerous active lesions. Frequently, these patients have symmetric extremity lesions.