Systemic Immune Response Syndrome After COVID-19 Immunization-Initial and Follow-up 18F-FDG PET/CT Imaging Appearances.

ABSTRACT

ABSTRACT A 46-year-old woman with previous history of breast cancer had follow-up 18F-FDG PET/CT 5 days after COVID-19 vaccination. In addition to avid axillary nodes, a well-documented feature, the scan demonstrated diffuse splenic and marrow uptake. Clinical history, laboratory, and scan findings were in keeping with SIRS (systemic inflammatory response). The patient recovered with supportive management. On follow-up, 18F-FDG PET/CT imaging 3 months later features had resolved. SIRS after vaccination may be observed on 18F-FDG PET/CT.