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

Laszlo Szekely; Bela Bozoky; Matyas Bendek; Masih Ostad; Pablo Lavignasse; Lars Haag; Jieyu Wu; Xu Jing; Soham Gupta; Elisa Saccon; Anders Sönnerborg; Yihai Cao; Mikael Björnstedt; Attila Szakos

doi:10.1016/j.heliyon.2021.e07134

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

Heliyon. 2021 May;7(5):e07134. doi: 10.1016/j.heliyon.2021.e07134. Epub 2021 May 24.

Authors

Laszlo Szekely¹, Bela Bozoky¹, Matyas Bendek¹, Masih Ostad¹, Pablo Lavignasse¹, Lars Haag¹, Jieyu Wu², Xu Jing^{2

3}, Soham Gupta⁴, Elisa Saccon⁴, Anders Sönnerborg⁴, Yihai Cao², Mikael Björnstedt¹, Attila Szakos¹

Affiliations

¹ Department of Pathology/Cytology, Karolinska University Laboratory, 141 86 Stockholm, Sweden.
² Microbiology and Tumor Biology Center, Karolinska Institutet, 171 77 Stockholm, Sweden.
³ The Second Hospital of Shandong University, Department of Clinical Laboratory, 250033 Jinan, China.
⁴ Department of Laboratory Medicine, Clinical Microbiology, Karolinska Institutet, 171 77 Stockholm, Sweden.

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, endothelium, 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.

Keywords: ARDS; Autopsy; COVID-19.