Bilateral orbital involvement in Erdheim-Chester disease.

Erdheim-Chester disease is an idiopathic condition characterized by a xanthogranulomatous process infiltrating the bones, lungs, heart, retroperitoneum and other tissues. This condition is often fatal. Ocular findings are rare. The authors report a case of bilateral xanthelasmas and bilateral massive orbital infiltration in a 61-year-old man with severe retroperitoneal fibrosis, renal and cardiovascular problems. The ophthalmic manifestations and differential diagnosis of this peculiar pathologic condition are discussed.