Papuloverrucous colloid milium: an occupational variant

We report a case of adult colloid milium in a 47-year-old mechanic with a l ong history of professional contact with lubricating oils and of sun exposu re. In addition to the typical translucent papules seen on the forehead, th ere were warty papules on the backs of both hands with unusual histological and ultrastructural features: marked hyperplasia of the epidermis with ort hokeratotic hyperkeratosis and papillary deposits of colloid material that were contiguous with the basal layer of the epidermis. The hand lesions cau sed by occupational exposure to mineral oils and solar radiation represent an occupational variant of adult colloid milium.