The IIIS includes the complement, contact, coagulation, and fibrinolysis systems, and is crucial for recognizing and eliminating microorganisms and debris in the body. It is also likely to be involved in the pathogenesis of COVID-19 ARDS.
The authors studied IIIS biomarkers, including C4d using the kit from Svar Life Science, from COVID-19 patients admitted to the intensive care unit. These analyses were compared to biochemical parameters and the clinical outcome of the patients.
The researchers found a strong association between the activation of IIIS with organ damage and death. Furthermore, they found that the complement system and especially the kallikrein/kinin system are strong prognostic markers of the outcome of the patients.
These findings suggest that it may be worth using existing kallikrein/kinin inhibitors for the treatment of critically ill COVID-19 patients.