[Severe Covid-19 comprises a self-amplifying loop of inflammation and coagulopathy].

Severe Covid-19 has a high mortality rate. Vital organ dysfunction results from pathophysiological self-amplifying loops of innate immunological hyperactivation, cytokine release, complement deposition, endothelial damage, and macro- and microvascular thromboembolism. Resulting alveolar exudation and pulmonary capillary thromboembolism lead to ventilation-perfusion mismatch, considered to be a primary cause of death in severe Covid-19. Therapeutic immunomodulation is believed to be safer and more effective during time periods with decreasing viral exposition and increasing inflammation.