Macroscopically, the lungs appear stained, with hyperemic / hemorrhagic areas alternating with pink areas. Histologically, some areas are severely emphysematous, with vastly dilated blood vessels (up to 20 times the norm) that often replace microthrombi.
In many cases, diffuse alveolar damage (DAD) is evident, with scaling of pneumocytes, formation of hyaline membranes, and fibrotic exudate (as in ARDS). It appears as a high-flow syndrome, with hepatomegaly, and dilated portal vessels with diffuse thrombosis. at all levels.
Even the heart seems enlarged, it always has a hydropericardium and a marked left ventricular hypertrophy (But hypertensive patients are almost always on anamnesis)
In one case, they observed a thrombus that almost completely obstructed the superior vena cava and the right atrium. They have often noticed the rise of the diaphragm, indicating that at one point the lungs no longer expand, associated with hepatomegaly.
While waiting to have data on CNS samples, Sessa requested a biopsy of the olfactory mucosa, COVID-19 classically gives anosmia and ageusia, could reach the brainstem trans-synaptically starting from the peripheral nerve endings of the olfactory or lingual nerve.
(thus as from the innervation of the lungs) In this scenario, part of the respiratory failure could be caused by direct damage of the virus in the nuclei of the brain stem (ambiguous nucleus, from the solitary tract)
