LAUSR

Abstract Coronavirus disease 2019 (COVID-19)–related pneumonia challenges clinical practice. We explore the potential diagnostic benefit of PET/CT to establish the underlying inflammatory or fibrotic repair processes in prolonged structural lung abnormalities in COVID-19 patients. Patients and Methods Six post COVID-19 patients suspected for pulmonary fibrosis were scheduled for dual-tracer PET/CT with 18F-FDG and 68Ga–fibroblast activation protein inhibitor (FAPI)–46. The uptake of 68Ga-FAPI-46 in the involved lung was compared with a control group of 9 non–COVID-19 patients. Clinical data and PET/CT imaging were collected and analyzed. Results PET/CT revealed in all 6 pulmonary impaired patients the reduced glucose avidity on 18F-FDG and clear positivity on 68Ga-FAPI-46 PET/CT in comparison to the control group. Conclusions Enhancing fibrotic repair mechanisms, 68Ga-FAPI PET/CT may improve noninvasive clinical diagnostic performance in patients with long-term CT abnormalities after severe COVID-19. Although this study shows promising results, additional studies in larger populations are required to establish a general diagnostic guideline.