Liver pathology in COVID-19 related death and leading role of autopsy in the pandemic

Abstract

Background: Information on liver involvement in patients with coronavirus disease 2019 is currently fragmented.

Aim: To highlight the pathological changes found during the autopsy of severe acute respiratory syndrome coronavirus 2 positive patients.

Methods: A systematic literature search on PubMed was carried out until June 21, 2022.

Results: A literature review reveals that pre-existing liver disease and elevation of liver enzyme in these patients are not common; liver enzyme elevations tend to be seen in those in critical conditions. Despite the poor expression of viral receptors in the liver, it seems that the virus is able to infect this organ and therefore cause liver damage. Unfortunately, to date, the search for the virus inside the liver is not frequent (16% of the cases) and only a small number show the presence of the virus. In most of the autopsy cases, macroscopic assessment is lacking, while microscopic evaluation of livers has revealed the frequent presence of congestion (42.7%) and steatosis (41.6%). Less frequent is the finding of hepatic inflammation or necrosis (19%) and portal inflammation (18%). The presence of microthrombi, frequently found in the lungs, is infrequent in the liver, with only 12% of cases presenting thrombotic formations within the vascular tree.

Conclusion: To date, the greatest problem in interpreting these modifications remains the association of the damage with the direct action of the virus, rather than with the inflammation or alterations induced by hypoxia and hypovolemia in patients undergoing oxygen therapy and decompensated patients.

Keywords: Autopsy; COVID-19; Immunofluorescence; Immunohistochemistry; In situ hybridization; Liver.