FDG PET/CT evaluation of a patient recovering from COVID-19.

A 48-year-old woman presented with 10-day history of cough and fever (up to 39.1 °C). Nasopharyngeal swab specimen was positive for COVID-19 nucleic acid test (RT-PCR). Detailed time course of the clinical data, laboratory tests, and imaging findings of computed tomography (CT) and [18F] fluorodeoxyglucose ([18F] FDG) positron emission tomography (PET/CT) are described in the figure. Chest CT obtained from day 7 to day 15 of the hospitalization showed GGOs (ground glass opacities) with crazy-paving pattern to consolidative opacities. Following antiviral (hydroxychloroquine hydrochloride and interferon) and anti-inflammatory (budesonide and albumin) treatment for several days, the patient was effectively relieved from clinical symptoms and was negative in two subsequent RT-PCR tests (day 13, day 14). [18F] FDG PET/CT scan (day 16) was performed to evaluate any other active disease process. It showed multiple FDG-positive consolidative opacities in both lungs (PET, fusion; SUVmax ranged 2.7–5.9) and multiple FDG-avid lymph nodes in the left subclavian, mediastinum, and hilum regions (arrows, fusion; SUVmax ranged 2.9–6.5) A follow-up chest CT acquired 2-month post-discharge (day 77) revealed few GGOs. RT-PCR was again negative. FDG-positive consolidative opacities in both lungs imply persistent inflammatory burden, while the patient was recovering and negative in RT-PCR. FDG-avid lymph nodes also suggest lingering lymphadenitis [1, 2]. FDG uptake may vary with different stages of virus and disease [3]. FDG PET/CT with its capability of directly mapping the location and activity of inflammation during virus exposure may have a role to play when there is uncertainty of diagnosis, for clinical management and for monitoring the effect of treatment [4].