CRP and COVID-19: cfDNA originating in multiple organs, including the kidney, heart, and lungs, has been detected in serum samples from COVID-19 patients [18], and the authors reported a correlation between cfDNA and inflammatory biomarkers, such as C-reactive protein (CRP) or D-dimer, as well as the overproduction of ROS by the self-sensing of cfDNA, suggesting an inflammatory feedback loop.