Xanthogranulomatous Osteomyelitis: Two Rare Cases Report

INTRODUCTION: Xanthogranulomatous osteomyelitis (XO) is a rare chronic inflammatory lesion that is histologically characterized by the presence of foamy histiocytes and plasma cells (1-8). Radiologic and gross examinations can mimic malignancy (9), so carful workup and definitive diagnosis should be made by histopathologic evaluation. Case Report:  There are two rare cases being reported here; the first one is a 21-year-old male who presented with chronic pain and swelling of upper leg for one year. He has history of healed traumatic fracture of fibula 7 years ago. Radiological examination revealed highly suspicious radio opaque lesions of upper fibula. The second case is a 30 years old female, presented with pain and swelling of wrist for six months with clinical suspicion of Ewing sarcoma. Radiological examination revealed highly suspicious radio opaque, lytic lesions of lower radius. Biopsy of both lesions were done. Microscopic examination showed marked chronic inflammatory cells infiltration mainly foamy histiocytes and lymphoid cells with many foreign body giant cells. No evidence of tuberculosis or malignancy. Conclusion: As these lesions were clinically highly suspicious of malignancy or associated with other diseases, so proper diagnostic roles in xanthogranulomatous osteomyelitis should include histopathological examination in order to rule out any malignant conditions of the bone.