Diagnosis and treatment of juvenile yellow granuloma in a child: A case report.

INTRODUCTION: Juvenile yellow granuloma (JXG) is a reactive proliferation of histiocytes rather than a true neoplasm. We present an extremely rare case of osseous JXG, which highlights the nonspecific imaging features and diagnostic challenges associated with this lesion. CASE PRESENTATION: This report describes the diagnosis and management of JXG in the proximal tibia of a 4-year-old Asian girl. The lesion was incidentally discovered following an ankle sprain. Imaging studies (X-ray, CT, MRI) initially suggested eosinophilic granuloma. Laboratory tests revealed elevated high-sensitivity C-reactive protein (43.84 mg/L) and erythrocyte sedimentation rate (63 mm/h). Biopsy revealed giant cell-rich tumors with foam cell aggregates. Immunohistochemistry was consistent with xanthoma. Given the large lesion size (6.8 × 3.5 × 3.1 cm) and involvement of the epiphyseal plate, the patient underwent robot-assisted curettage, implantation of artificial bone/cement, Kirschner wire fixation, and cast immobilization. Final pathological diagnosis, confirmed by immunohistochemistry (CD68+, CD163+, S-100-), was JXG. CONCLUSIONS: This case underscores the rarity and imaging nonspecificity of osseous JXG, emphasizing the critical role of histopathology combined with immunohistochemistry for definitive diagnosis. A multimodal treatment approach involving curettage, epiphyseal plate protection, and mechanical stabilization achieved a successful outcome. Long-term follow-up is necessary to monitor for potential epiphyseal injury and recurrence.