Solitary eosinophilic granuloma of humerus in a 2-month-old infant: A case report with 3 years follow-up

Eosinophilic granulomais (EG) a benign self-limiting disease which belongs to the spectrum of Langerhans cell histiocytosis. It is characterized by single or multiple skeletal lesions involving skull, mandible, ribs, spine and long bones predominately in children <12 years. We report a relatively rare case of left proximal humerus solitary EG in a month old infant who was brought to us with reduced movements of left upper limb and swelling of left shoulder. X-ray revealed osteolytic lesion in left upper humerus. No associated lesions were revealed by other imaging modalities. Open biopsy and curettage of lesion revealed proliferation of histiocytes with an infiltration of eosinophils. Immunohistochemistry was positive for S-100 and CD1a. Hence, diagnosis of solitary EG was made. Baby was followed up every 6 monthly for 3 years. There was no evidence of recurrence or detection of new lesion elsewhere at last follow-up