Andrea Rodríguez Trigueros, Department of Internal Medicine, Virgen del Rocío Hospital, Sevilla, Spain
José Ramón Lopez-Morales, Department of Internal Medicine, Virgen del Rocío Hospital, Sevilla, Spain
José Carlos Alarcón García, Department of Internal Medicine, Virgen del Rocío Hospital, Sevilla, Spain
Santiago Rodríguez Suárez, Internal Medicine, Department of Rare Disease, Virgen del Rocío Hospital, Sevilla, Spain
Pilar Sancho, Department of Oncology, Virgen del Rocío Hospital, Sevilla, Spain
José Salvador García-Morillo, Autoimmune and Minority Diseases Unit. Internal Medicine Department. Hospital Universitario Virgen del Rocío, Sevilla. Systemic Autoimmune Diseases Working Group (GEAS-SEMI), Spain

Erdheim-Chester disease (ECD) is a non-Langerhans histiocytic that typically affects middle-aged adults between the fifth and seventh decades of life. It is characterized by systemic xanthogranulomatous infiltration by histiocytes CD68+/CD1a–. In this paper, we collect the main clinical characteristics of eleven patients, diagnosed with ECD at the Virgen del Rocio Hospital in Seville. After first medical contact, it has been possible to reduce the misdiagnoses and this has shortened the time to diagnosis and initiation of treatment, which has resulted in fewer complications.

Keywords: Erdheim-Chester disease. Non-langerhans histiocytosis. Bone tumor. Rare disease.