Erdheim-Chester disease.

A 38-year-old man presented with numerous dermal nodules, similar to xanthoma disseminatum, that were histologically consistent with his diagnosis of Erdheim-Chester disease, a non-Langerhans cell histiocytosis. Other cutaneous manifestations of this disease include eyelid xanthelasma, pretibial dermopathy and pigmented lesions of the lips and buccal mucosa. The histological diagnosis of Erdheim-Chester disease was originally made on the patient's retroperitoneal tissue, obtained at a laparotomy for surgical treatment of a presumed phaeochromocytoma, and confirmed by the pathognomonic long bone X-ray findings of this disease.