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

Area of Science:

• Nuclear medicine imaging
• Infectious disease research
• Cardiovascular pathology

Background:

• Persistent symptoms after SARS-CoV-2 infection are common.
• The underlying mechanisms for these long-term effects remain unclear.
• Evaluating persistent inflammatory processes is crucial for understanding post-COVID conditions.

Purpose of the Study:

• To assess if 2-deoxy-2-[18F]fluoro-D-glucose ([18F]FDG) positron emission tomography/computed tomography ([18F]FDG-PET/CT) can detect persistent inflammation in recovered COVID-19 patients.
• To investigate potential vascular inflammation as a cause of lingering symptoms.

Main Methods:

• Adult patients with persistent symptoms (>30 days) post-COVID-19 underwent whole-body [18F]FDG-PET/CT.
• Imaging was analyzed qualitatively and semi-quantitatively using target-to-blood pool ratios.
• Controls included oncologic patients with negative follow-up [18F]FDG-PET/CT scans.

Main Results:

• Ten recovered COVID-19 patients showed increased [18F]FDG uptake in bone marrow and blood vessels.
• Bone marrow uptake and total vascular scores did not differ significantly between patients and controls.
• The target-to-blood pool ratio was notably higher in recovered COVID-19 patients compared to controls.

Conclusions:

• Despite similar overall vascular scores, specific arterial regions showed higher [18F]FDG uptake in the COVID-19 cohort.
• These findings suggest SARS-CoV-2 can induce vascular inflammation.
• This inflammation may contribute to the unexplained persistent symptoms experienced by some recovered patients.