Validation of the Analysis Methodology Behind the Use of Quantitative 18F-FDG PET/CT to Assess Lung Inflammation

"PET/CT will be performed at Cambridge University Hospital's PET-CT unit, Cambridge.~Participants in Part A of the study (sarcoidosis and HVs) will receive one PET/CT scan. A Cine-CT scan will be performed immediately prior to the 18F-FDG PET/CT scan. Settings for the CT scans will be determined by clinical protocols, radiation dose will be kept as low as reasonably practicable (ALARP) consistent with UK legislation.~After 6 hours of fasting and if blood glucose concentration is ≤11mmol/L participants will proceed to undergo an 18FDG PET/CT scan.~18F-FDG will be administered intravenously at a dose of approximately 200 MBq.~Positron emission scanning will involve a 60-minute dynamic acquisition from the lungs."

In Part B, eight healthy volunteers will undergo an LPS challenge whereby each participant is injected with the challenge agent, Lipopolysaccharide (LPS), to invoke temporary mild lung inflammation. Each participant will have a PET/CT scan before and after the administration of LPS and the images will be assessed to determine whether these methods are able to detect true lung inflammation.

In Part B, four healthy volunteers will undergo a saline challenge as outlined above for the LPS challenge. Pre- and post-challenge scans will provide control data for the study.

For women whose post-menopausal status and/or pregnancy status is uncertain at screening, a blood sample will be collected to test for pregnancy and menopausal status (hormone profiling) before enrolling them on to the study. If pregnancy status is still uncertain at study visits, participants will have a urine pregnancy test before undergoing any PET/CT scans to ensure it is safe for them to continue in the study.