Sternoclavicular xanthogranulomatous osteomyelitis in a patient after kidney transplantation: a case report.

Xanthogranulomatous osteomyelitis (XO) is a rare chronic inflammatory bone disease characterized by the presence of cholesterol-laden foam macrophages, histiocytes, and plasma cells. We report the case of a 41-year-old man with end-stage renal disease who had undergone deceased donor kidney transplantation 4 years earlier. He presented with a chest wall mass that he had first identified 2 weeks prior to admission. Computed tomography revealed a periosseous heterogeneously enhancing soft tissue mass adjacent to the sternal end of the left clavicle, accompanied by irregular and destructive osteolytic lesions on the left side of the sternal manubrium. A total mass resection, which included partial clavicle and sternum removal, was performed. Pathological examination revealed foamy histiocytes along with numerous lymphoplasmacytic cells, confirming the diagnosis of XO. This case underscores the potential for XO to develop following kidney transplantation.