False-positive MIBG uptake in pneumonia in a patient with stage IV neuroblastoma.

A 32-month-old female child with a history of stage IV favorable biology neuroblastoma with a 123-I MIBG (metaiodobenzylguanidine scan) avid adrenal mass, with retroperitoneal nodal extension and bony metastasis, was in complete remission after intense multimodal therapy. Seventeen months after diagnosis a surveillance 123-I MIBG scan showed abnormal tracer uptake in the midzone of the right thorax. Chest x-ray and CT scan confirmed right upper lobe consolidation corresponding to the tracer uptake. Chest x-ray after antibiotics showed resolution of the abnormality. 123-I MIBG scan 3 months later showed no abnormal uptake. False-positive MIBG uptake in pneumonia has not been previously reported.