A 48-year-old woman working in the Wuhan Union Hospital presented with an 8-day history of fever (37–38 °C) accompanied by chills, dry cough, myalgia, and fatigue. WBC count was within the reference range, but she had increased hsCRP levels (12.2 mg/L). A search for known respiratory pathogens yielded negative findings. Chest CT imaging (January 15, 2020, Fig. 4d) led to the identification of a blurry shadow in the right lower lung lobe. A subsequent 18F-FDG PET/CT scan (January 20, 2020) revealed the presence of peripheral FDG-avid GGOs with interlobular septal thickening in both lungs (SUVmax range 3.7–9.3; Fig. 4a, b, arrows). When compared with previous chest CT results, there was evidence of disease progression as shown by a higher number of lesions, which were also characterized by an increased extent and density. There were also multiple FDG-positive lymph nodes in the mediastinum and right hilar region (SUVmax range 3.8–5.5; Fig. 4c, arrows). Real-time fluorescent polymerase chain reaction (RT-PCR) for the detection of SARS-CoV-2 nucleic acid yielded negative findings in two independent measurements. A follow-up chest CT (February 1, 2020) performed after antiviral and anti-infective treatment revealed a significant improvement in the picture (Fig. 4d).
Fig. 4 Peripheral FDG-avid GGOs with interlobular septal thickening in both lungs and multiple FDG-positive lymph nodes in the mediastinum and right hilar region