**6. Conclusions**

18F-FDG is extremely useful in the diagnostic workup of patients suspected of having infection. It has emerged as the molecular imaging test of choice for spondylodiscitis, FUO in both adults and children, sarcoid, and vasculitis. This test is also valuable in the diagnostic workup of patients with diabetic foot and cardiovascular infections. The most significant limitation of 18F-FDG is a lack of specificity. Investigators have sought to capitalize on the advantages of PET over single photon emitting radiopharmaceuticals, by developing PET radiopharmaceuticals that are more specific for infection. Early efforts focused on *in vitro* labeling of leukocytes with PET radiopharmaceuticals but for a variety of reasons, these agents have not entered the clinical arena, nor is it likely that they will. Initial results with 124I-FIAU were encouraging, but subsequent data dampened the enthusiasm for this agent. Based on preliminary data, 18F-FDS and 68Ga labeled siderophores and AMPs show promise as infection-specific agents. However, clinical trials are needed to establish their value.
