The Koebner phenomenon in eruptive xanthoma.

A 49-year-old woman with Type V hyperlipidemia had yellow papules smaller than 3 mm in diameter with red haloes on her elbows, shoulder, buttocks, and hands. Two linear lesions composed of papules arising at the sites of skin previously injured by a cat scratch were observed. Histopathological examination of these papules revealed the presence of many foam cells in the dermis which stained positively with oil red O stain. A survey of the literature found only 5 cases of the Koebner phenomenon in xanthoma.