Bilateral and extensive xanthelasma palpebrarum in a young man.

A 25-year-old white man had been aware since childhood of yellow discolorations of the medial aspects of his upper lids. The skin changes progressively spread to involve all four eyelids, the inferior skin of the brow, and the lateral and medial canthal skin. The clinical diagnosis was extensive bilateral xanthelasmas . The patient had no manifest abnormality of lipid metabolism, although his father and grandfather had both developed xanthelasmas early in childhood. A snip biopsy of upper lid skin was performed and studied by both light and electron microscopy. The light microscopic appearance confirmed the diagnosis of xanthelasma, in that the upper dermis contained mono- and multinucleated foamy xanthoma cells beset with myriad cytoplasmic vacuoles. Cells displaced outwardly into the interstitium evidenced degradation phenomena within the vacuoles, consisting of lamellar bodies or fingerprint-like inclusions, presumably the result of fusion of lysosomes with the lipidic inclusions. Scattered non- lipidized mononuclear histiocytes with abundant profiles of smooth-surfaced endoplasmic reticulum possibly represented a reserve population of monocytes for conversion into xanthoma cells.