[A case of Langerhans cell histiocytosis coincident with severe external ear canal inflammation].

We report a case of Langerhans cell histiocytosis (LCH), a rare disease caused by the proliferation of abnormal Langerhans cells, coincident with severe external ear canal inflammation. A 27-year-old man with a 1-year history of external ear canal discharge was found in computed tomography (CT) to have left temporal bone erosion with tissue granulation. Chest X-ray showed pulmonary fibrosis, necessitating transbronchial lung biopsy that yielded a definitive diagnosis of multisystem, multisite LCH involving the bone, skin, lung, pituitary, thyroid, and lymph node systems.