Diagnostic guidance for patients with persistent pulmonary abnormalities after COVID-19 infection: the potential benefit of 68Ga-FAPI PET/CT

Abstract Coronavirus disease 2019 (COVID-19)-related pneumonia challenges clinical practice. We explore the potential diagnostic benefit of positron emission tomography/computed tomography (PET/CT) in order to establish the underlying inflammatory or fibrotic repair processes in prolonged structural lung abnormalities in COVID-19 patients.Methods: Six post-COVID-19 patients suspected for pulmonary fibrosis were scheduled for dual tracer PET/CT with 18 F-FDG (fluorodeoxyglucose) and 68Ga-fibroblast activation protein inhibitor (FAPI)-46. The uptake of 68 Ga FAPI-46 in the involved lung was compared to a control group of nine non COVID-19 patients. Clinical data and PET/CT imaging were collected and analysed.Results: PET/CT revealed in all six pulmonary impaired patients the reduced glucose avidity on 18 F-FDG and clear positivity on 68 Ga-FAPI-46 PET/CT in comparison to the control group. Conclusion: Indicating fibrotic repair mechanisms, 68 Ga-FAPI PET/CT may enhance non-invasive clinical diagnostic performance, drive therapeutic interventions, and facilitate therapeutic response monitoring in patients with long-term CT-abnormalities after severe COVID-19.