We report the case of a young boy referred to our Department of Nuclear Medicine under the suspicion of a malignant tumor. The leading clinical symptoms were pain in the joints and loss of weight and vitality. Radiographic findings were suggestive of osteogenic sarcoma, but bone scans showed multiple increased tracer depositions along the cortex of femur and tibia, and in the lower and upper jaw. The enrichment pattern was not typical for metastases, but more probably demonstrated the multiple foci of osteomyelitis. This assumption was confirmed by the histological findings, which were diagnosed as primary chronic osteomyelitis. This rare pediatric bone disorder has been described by Giedion et al. The etiology of the disease is unknown, and therapy is discussed controversely in literature.