Eosinophilic granulomas are associated with:
A. Langerhans cell histiocytosis (LCH)Eosinophilic granulomas are benign osteolytic lesions. Eosinophilic granulomas of the ribs can occur as solitary lesions or as part of a more generalized disease process of the lymphoreticular system termed Langer hans cell histiocytosis (LCH). In LCH, the involved tissue is infiltrated with large numbers of histiocytes (similar to Langerhans cells seen in skin and other epithelia), which are often organized as granulomas. The cause is unknown. Of all LCH bone lesions, 79% are solitary eosinophilic granulomas, 7% involve multiple eosinophilic granulomas, and 14% belong to other forms of more systemic LCH. Isolated single eosinophilic granulomas can occur in the ribs or skull, pelvis, mandible, humerus, and other sites. They are diagnosed primarily in children between the ages of 5 and 15 years. Because of the associated pain and tenderness, they may be confused with Ewing sarcoma or with an inflammatory process such as osteomyelitis. Healing may occur spontaneously, but the typical treatment is limited surgical resection with a 2-cm margin.