Two enlarged kidneys: a manifestation of Erdheim-Chester disease

Erdheim-Chester disease is a rare form of non-Langerhans' cell histiocytosis. This disorder is characterized by a bone involvement and several extraskeletal manifestations. We describe the case of a patient with a pleural and pericardial effusion leading to tamponade. Pathological examination of pericardium and mediastinal adenopathy was normal. The abdominal computed tomography scan showed two enlarged kidneys suggestive of Erdheim-Chester disease. Bone scan scintigraphy demonstrated symmetrical increased labeling of the long bones. The biopsy of perirenal soft tissue confirmed the diagnosis of Erdheim-Chester disease.