COVID-19: a closer look at the pathology in two autopsied cases. Is the pericyte at the center of the pathological process in COVID-19?

We performed autopsies on two cases of COVID-19. The microcirculations of all organs were the site of the pathological findings. Thrombotic microangiopathy was found in the brain and also the kidneys. Vasculitis was also a feature of the autopsy findings, together with portal triaditis of the liver. The major pathological findings in both cases were fibrin deposits. Within the lung, the fibrin deposits were observed in the alveolar microcirculation in sub-endothelial locations of capillaries, arterioles, post capillary venules, and the adventitia of larger vessels. These fibrin deposits in the lungs occurred at the sites where pericytes are located in these vessels. The pericyte with its high concentration of ACE-2 receptors and its procoagulant state may represent one of the primary sites of action of SARS-CoV-2. A review of pericytes in health and disease is undertaken. COVID-19 is a disease of the microcirculation.

Coronavirus 229E with Rhinovirus co-infection causing severe acute respiratory distress syndrome with thrombotic microangiopathy and death during Covid-19 pandemic: lessons to be learnt

We report on a 3-month old infant male who had a seven-days history of fever and rhinorrhea associated with wheezing prior to his death, during the Covid-19 pandemic. Viral testing for Covid-19 (SARS-CoV-2) was negative but was positive for Coronavirus 229E and RP Human Rhinovirus. The pulmonary histological examination showed diffuse alveolar damage along with thrombotic microangiopathy affecting alveolar capillaries. Also, thrombotic microangiopathy was evident in the heart, lungs, brain, kidneys and liver. Thrombotic microangiopathy is a major pathologic finding in Acute Respiratory Distress Syndrome and in the multiorgan failure. This is the first report that illustrates thrombotic microangiopathy occurring in lung, heart, liver, kidney and brain in Acute Respiratory Distress Syndrome with Coronavirus 229E with Rhinovirus co-infection. The clinical presentation and pathological findings in our case share common features with Covid-19.