Development of Specific Radiopharmaceuticals for Infection Imaging by Targeting Infectious Micro-organisms

Infectious diseases remain a major health problem and cause of death worldwide. A variety of radiopharmaceuticals are used for the imaging of infections and inflammation in the practice of nuclear medicine. Long-term clinical use has shown that the majority of radiolabeled probes cannot distinguish between inflammation and infection. Gallium-67-citrate binds to bacteria, but also to proteins ac-cumulating at both sterile inflammation and bacterial infection sites. Other agents are used to interact with receptors or domains on circu-lating and infiltrating leukocytes or to label them directly. However, these probes cannot distinguish between infection and inflammation because they are not specific to infectious micro-organisms. This review examines the recent developments and applications of radiola-beled specific agents, such as antiviral drugs, antifungal, antibiotics and antimicrobial peptides, to visualize infectious foci by targeting viruses, fungi or bacteria.