[An ophthalmologic diagnostic error leading to a rare systemic diagnosis: Erdheim-Chester disease].

[erdheim-chester disease]

Erdheim-Chester disease is a rare systemic disease . The diagnosis is difficult due to significant clinical and morphological polymorphism . Orbital involvement is rare , but constitutes a classic means of detection .We report the case of a 60 -year -old man , who consulted for evaluation of bilateral retro-orbital tumors . These tumors had been discovered on head CT two years previously during work-up of proptosis . Two biopsies were performed . The first one revealed polymorphous inflammatory tissue . The second one revealed intense granulomatous reaction , rich in non-specific foamy histiocytes . Thoracic -abdominal -pelvic CT scan detected peri-aortic and retroperitoneal infiltration . The association of these signs pointed to a diagnosis of Erdheim-Chester disease , confirmed by the re -examination of the histological samples .Erdheim-Chester disease is a rare non-Langerhans histiocytosis with a specific tropism for perivascular and fatty connective tissue . The cause is not known . The diagnosis of this systemic disease is histological .In the case of bilateral intra-orbital tumors , the diagnosis of Erdheim-Chester disease must be considered .