Biodistribution and Radiation Dosimetry of the Enterobacteriaceae-Specific Imaging Probe [¹⁸F]Fluorodeoxysorbitol Determined by PET/CT in Healthy Human Volunteers

Purpose: [¹⁸F]fluorodeoxysorbitol ([¹⁸F]FDS) is the first radiopharmaceutical specific for a category of bacteria and has the potential to specifically detect Enterobacteriaceae infections. The purpose of this study was to testify the safety and investigate the biodistribution and radiation dosimetry of [¹⁸F]FDS in healthy human bodies. Procedures: Six healthy subjects were intravenously injected with 320–520 MBq [¹⁸F]FDS. On each subject, 21 whole-body emission scans and a brain scan were conducted at settled time points within the next 4 h. Residence time for each source organ was determined by multi-exponential regression. Absorbed doses for target organs and effective dose were calculated via OLINDA/EXM. Results: No adverse events due to [¹⁸F]FDS injection were observed in the study. The tracer was cleared rapidly from the blood pool through the urinary system. A small portion was cleared into the gut through the hepatobiliary system. The effective dose (ED) was estimated to be 0.021 ± 0.001 mSv/MBq. The organ receiving the highest absorbed dose was the urinary bladder wall (0.25 ± 0.03 mSv/MBq). Conclusions: [¹⁸F]FDS is safe and well tolerated. The effective dose was comparable to that of other F-18 labeled radiotracers. [¹⁸F]FDS is suitable for human use from a radiation dosimetry perspective.