Injury patterns in
COVID-19 lungs

Covid19 pneumonia

Perivascular Inflammatiion

We showed clotted blood vessels with a pronounced inflammation around the smaller blood vessels.

We identified the inflammatory infiltrate to consist predominantly of T-cells: CD3 (white), CD4 (green), CD8 (yellow), CD20 (purple), CD68 (red) and cell nuclear stain (blue).

Lung alveoli with hyaline membranes and new blood vessels

Covid-19 lungs showed showed a characteristic formation of eosinophilic hyaline membranes (arrows) superimposed on the mildly edematous alveolar walls and new blood vessel formation (angiogenesis).

Aberrant angiogenesis

COVID19-lungs showed an aberrant angiogenesis with a high occurence of intussusceptive angiogenesis and partly vascular disruption.

Intussusception

Intussusceptive angiogenesis was identified via the occurrence of tiny holes with a diameter of 2-5 μm. Microvascular alterations by intussusceptive angiogenesis may contribute as one of the pivotal pathogenetic mechanisms in the progression of disease of COVID-19.