[Retroperitoneal complications of Erdheim-Chester disease].

Erdheim-Chester disease is a non-langerhans cell histiocytosis. It is a rare and plurifocal disease. Retroperitoneal involvement manifests as a mass associated with fibrosis, which is well visualized on CT scan and MRI. This disease is characterized by its potential to involve the whole retroperitoneum. We report a case of this disease that developed over twenty years, consisting of renal arteries stenosis, bilateral ureteral stenosis and evolutive adhesive capsulitis.