[Langerhans cell histiocytosis with isolated sternum involvement. A clinical case]

The Langerhans Cell Histiocytosis (LCH) is a rare condition, characterized by the proliferation of dendritic cells. Its clinical presentation is variable and ranges from an isolated skin or bone disease, mainly the skull, to a life-threatening multisystemic disease. This case is about a healthy 8-year-old girl with a history of four days of severe sternum pain and no other symptomatology. At the initial evaluation at the emergency department a chest X-ray (Figure 1) and thoracic computed tomography scan with 3-D reconstruction were performed and they showed the sternal osteolytic lesion (Figure 2). She was admitted to the hospital for further evaluation. The immunohistochemistry evaluation of the fine needle aspiration sample was positive for CD1a, confirming the diagnosis of histiocytosis. The patient received methylprednisolone 40 mg/ day with clinical improvement.