Association of inflammatory markers with the severity of COVID-19

Furong Zeng; Ying Guo; Mingzhu Yin; Xiang Chen; Guangtong Deng

CRP is an exquisitely sensitive systemic marker of acute-phase response in inflammation, infection, and tissue damage, which could be used as indicator of inflammation (Pepys and Hirschfield, 2003) . In Chen L et al. study, although no statistically significant difference was found in the level of CRP between non-severe and severe group, the mean level of CRP was higher in severe group than non-severe group . Other studies all reported CRP level was positively related to the severity of COVID-19. PCT is also a main inflammatory marker routinely measured in clinical practice. Among 9 studies, the levels of PCT were all higher in severe group than non-severe group. ESR is a non-specific inflammatory marker, which mainly reflects the changes of plasma protein types (Wu et al., 2018) . In our metaanalysis, we found higher ESR level in severe group than non-severe group. One reason is that patients in severe group had higher inflammation. Another possible explanation is that patients with older age in severe group contributed to the higher level of ESR considering that the level of ESR increased with age (Piva et al., 2001) .