Laboratory biomarkers associated with COVID-19 severity and management.

Keddie, S.; Ziff, O. J.; Chou, M. K.; Taylor, R. L.; Heslegrave, A.; Garr, E.; Lakdawala, N.; Church, A.; Ludwig, D.; Manson, J.; Scully, M.; Nastouli, E.; Chapman, M. D.; Hart, M.; Lunn, M. P.

The heterogeneous disease course of COVID-19 is unpredictable, ranging from mild self-limiting symptoms to cytokine storms, acute respiratory distress syndrome (ARDS), multi-organ failure and death. Identification of high-risk cases will enable appropriate intervention and escalation. This study investigates the routine laboratory tests and cytokines implicated in COVID-19 for their potential application as biomarkers of disease severity, respiratory failure and need of higher-level care. From analysis of 203 samples, CRP, IL-6, IL-10 and LDH were most strongly correlated with the WHO ordinal scale of illness severity, the fraction of inspired oxygen delivery, radiological evidence of ARDS and level of respiratory support (p[≤]0.001). IL-6 levels of >3.27pg/ml provide a sensitivity of 0.87 and specificity of 0.64 for a requirement of ventilation, and a CRP of >37mg/L of 0.91 and 0.66. Reliable stratification of high-risk cases has significant implications on patient triage, resource management and potentially the initiation of novel therapies in severe patients.