Pulmonary stromal expansion and intra-alveolar coagulation are primary causes of Covid-19 death

Szekely, L.; Bozoky, B.; Bendek, M.; Ostad, M.; Lavignasse, P.; Haag, L.; Wu, J.; Jing, X.; Gupta, S.; Saccon, E.; Sonnerborg, A.; Cao, Y.; Bjornstedt, M.; Szakos, A.

doi:10.1101/2020.12.23.424172

bioRxiv · 10.1101/2020.12.23.424172

Pulmonary stromal expansion and intra-alveolar coagulation are primary causes of Covid-19 death

Szekely, L.·Bozoky, B.·Bendek, M.·Ostad, M.·Lavignasse, P.·Haag, L.·Wu, J.·Jing, X.·Gupta, S.·Saccon, E.·Sonnerborg, A.·Cao, Y.·Bjornstedt, M.·Szakos, A.

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Abstract

Most Covid-19 victims are old and die from unrelated causes. Here we present twelve complete autopsies, including two rapid autopsies of young patients where the cause of death was Covid-19 ARDS. The main virus induced pathology was in the lung parenchyma and not in the airways. Most coagulation events occurred in the intra-alveolar and not in the intra-vascular space and the few thrombi were mainly composed of aggregated thrombocytes. The dominant inflammatory response was the massive accumulation of CD163+ macrophages and the disappearance of T killer, NK and B-cells. The virus was replicating in the pneumocytes and macrophages but not in bronchial epithelium, endothel, pericytes or stromal cells. The lung consolidations were produced by a massive regenerative response, stromal and epithelial proliferation and neovascularization. We suggest that thrombocyte aggregation inhibition, angiogenesis inhibition and general proliferation inhibition may have a roll in the treatment of advanced Covid-19 ARDS.

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Szekely, L., Bozoky, B., Bendek, M., Ostad, M., Lavignasse, P., Haag, L., Wu, J., Jing, X., Gupta, S., Saccon, E., Sonnerborg, A., Cao, Y., Bjornstedt, M., Szakos, A.. 2020-12-26. Pulmonary stromal expansion and intra-alveolar coagulation are primary causes of Covid-19 death. https://doi.org/10.1101/2020.12.23.424172

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