Vasculitis changes in COVID-19 survivors with persistent symptoms: an [ 18 F]FDG-PET/CT study

Eur J Nucl Med Mol Imaging. 2021 May;48(5):1460-1466. doi: 10.1007/s00259-020-05084-3. Epub 2020 Oct 30.


Purpose: Several patients experience unexplained persistent symptoms after SARS-CoV-2 recovering. We aimed at evaluating if 2-deoxy-2-[18F]fluoro-D-glucose ([18F]FDG) was able to demonstrate a persistent inflammatory process.

Methods: Recovered adult COVID-19 patients, who complained unexplained persisting symptoms for more than 30 days during the follow-up visits, were invited to participate in the study. Patients fulfilling inclusion criteria were imaged by [18F]FDG positron emission tomography/computed tomography ([18F]FDG-PET/CT). Whole-body [18F]FDG-PET/CT, performed according to good clinical practice, was qualitatively (comparison with background/liver) and semi-quantitatively (target-to-blood pool ratio calculated as average SUVmax artery/average SUVmean inferior vena cava) analyzed. Negative follow-up [18F]FDG-PET/CT images of oncologic patients matched for age/sex served as controls. Mann-Whitney test was used to test differences between groups. SPSS version 26 was used for analyses.

Results: Ten recovered SARS-CoV-2 patients (seven male and three females, median age 52 years, range 46-80) with persisting symptoms were enrolled in the study. Common findings at visual analysis were increased [18F]FDG uptake in bone marrow and blood vessels (8/10 and 6/10 cases, respectively). [18F]FDG uptake in bone marrow did not differ between cases and controls (p = 0.16). The total vascular score was similar in the two groups (p = 0.95). The target-to-blood pool ratio resulted higher in recovered SARS-CoV-2 patients than in controls.

Conclusion: Although the total vascular score was similar in the two groups, the target-to-blood pool ratio was significantly higher in three vascular regions (thoracic aorta, right iliac artery, and femoral arteries) in the recovered COVID-19 cohort than in controls, suggesting that SARS-CoV-2 induces vascular inflammation, which may be responsible for persisting symptoms.

Keywords: Infection; Inflammation; Long COVID; SARS-CoV-2; Vasculitis; [18F]FDG-PET/CT.

MeSH terms

  • Adult
  • Aged
  • Aged, 80 and over
  • COVID-19*
  • Female
  • Fluorodeoxyglucose F18
  • Humans
  • Male
  • Middle Aged
  • Positron Emission Tomography Computed Tomography
  • Positron-Emission Tomography
  • Radiopharmaceuticals
  • SARS-CoV-2
  • Survivors
  • Vasculitis*


  • Radiopharmaceuticals
  • Fluorodeoxyglucose F18