Contribution of 18F-Fluorodeoxyglucose to the Identification of Dubious Lesions Caused by SARS-CoV-2

Coronavirus disease, caused by the SARS-CoV-2 virus, has caused a global health crisis. While RT-PCR remains the gold standard for diagnosis, its limited sensitivity, especially in the early stages, has highlighted the need for complementary diagnostic tools. Among these, [18F]FDG PET/CT has gained attention for its potential role in detecting inflammation and metabolic activity associated with COVID-19. This review aims to provide an overview of current diagnostic techniques for COVID-19 and to explore the application of [18F]FDG PET/CT imaging in the detection and monitoring of SARS-CoV-2 infection. A comprehensive literature review was conducted on molecular, serological, and imaging-based diagnostic techniques for COVID-19, with a focus on the biological mechanism, clinical applications, and diagnostic performance of [18F]FDG PET/CT in COVID-19 patients. [18F]FDG PET/CT has demonstrated the ability to detect increased metabolic activity in COVID-19 associated pulmonary lesions, particularly ground-glass opacities, often preceding detectable morphological changes on CT. The imaging also revealed uptake in lymph nodes, bone marrow, and extrapulmonary tissues, reflecting systemic inflammation. [18F]FDG PET/CT represents a promising additional tool for the evaluation of inflammation and disease progression in COVID-19. However, further studies are required to define its role, optimize protocols, and assess its risk–benefit profile in the clinical setting.