Gallium-68-CXCR4-PET/CT chemokine receptor-targeting imaging in acute SARS-Cov-2 infection: a case report

Abstract

Ziel/Aim Single-patient report on the pattern of CXCR4 expression in a patient presenting with acute respiratory SARS-Cov-2 (COVID-19) infection after hybrid imaging with Ga-68-pentixafor-PET/non-ceCT (CXCR4-PET). Methodik/Methods 37-year-old man presenting with pneumonia, severe ARDS, requiring mechanical ventilation and acute supportive therapy. Later diagnose of bacterial superinfection with septic shock, persistent high fever (>40 °C) and elevated inflammation markers, non-responsive to wide-spectrum antibiotics. 178 MBq of Ga-68-pentixafor then administered in accordance with the responsible regulatory body after obtaining informed consent. Whole-body imaging followed on a dedicated PET-scanner 1h post-injection. Low-dose CT scans for attenuation correction were acquired (top of the skull to proximal tibias). Ergebnisse/Results CRCX4-PET showed only faint pulmonary uptake in parallel with significantly enhanced, diffuse tracer-uptake in the bone marrow (spine, thorax and pelvis) as well as in the spleen. Increased CXCR4-expression in the pharyngeal/palatine tonsils, CXCR4-positive lymph nodes in the neck/thorax as well as abdominal/inguinal regions was also reported. Focal soft-tissue uptake was detected in the distal right thigh, showing a characteristic peripheral tracer distribution strongly suggestive of intramuscular inflammatory focus. Schlussfolgerungen/Conclusions Ga-68-pentixafor-PET/low-dose-CT hybrid imaging showed foci of increased CXCR4-expression other than the lungs in a SARS-Cov-2 patient presenting with persistent high fever. Although lacking validation data, this single case suggests a role of CXCR4-targeted hybrid imaging in acute inflammatory conditions such as COVID-19 infections and warrants further prospective studies to evaluate its potential role in guiding clinical management in a more complex setting of systemic, multi-organ infectious/inflammatory disease.