A Case of Erdheim-Chester Disease with Omental Caking Initially Mistaken for a Malignancy

: Erdheim-Chester disease (ECD) is an uncommon non-Langerhans cell histiocytosis. Bilateral symmetric sclerosis of the long bones and possible multiorgan involvement are main presentations this disease. Histologically, lipid-laden foamy histiocytes positive immunochemically for CD68 (occasionally PS100) negative S100 CD1a in ECD. Herein, we describe case a 35-year-old man diagnosed with ECD peritoneal retroperitoneal infiltrations bone involvement. The diagnosis was only confirmed after two years non-specific abdominal pain, nausea, weight loss. Primarily, patient’s clinical symptoms computed tomography (CT) findings, which indicated omental caking, thickening, perinephric soft tissue density, suggested intra-abdominal malignancy. Finally, biopsy carried out, demonstrated xanthogranulomatous from Further radiographic skeletal survey based on histopathological results showed osteosclerosis bones. Although ECD, associated infiltrations, finding, it should be included differential patients gastrointestinal manifestations, along typical radiological findings.