Eosinophilic granuloma of bone in the growing epiphysis.

Eosinophilic granuloma of bone is a rare skeletal manifestation of one of the spectrum of diseases known as histiocytosis X. These lesions often simulate other pathophysiologic processes (Ewing sarcoma, chronic osteomyelitis, Brodie abscess, and chondroblastoma) and may present significant diagnostic problems. Three additional cases of eosinophilic granuloma in an epiphysis are reviewed in this report. Transphyseal extension was present in all our cases and in five of 10 cases documented in the literature. Diagnosis demands accurate biopsy and histopathologic evaluation. Treatment and prognosis are individualized.