Histopathology


. 2022 Aug 4.
doi: 10.1111/his.14734. Online ahead of print.
Cardiac megakaryocytes in SARS-CoV-2 positive autopsies


Kara L Gawelek 1 , Robert Padera 1 , Jean Connors 2 , Geraldine S Pinkus 1 , Olga Podznyakova 1 , Elisabeth M Battinelli 2



Affiliations

Abstract

Thromboembolic phenomena are an important complication of infection by severe acute respiratory coronavirus 2 (SARS-CoV-2). Increasing focus on management of the thrombotic complications of Coronavirus Disease 2019 (COVID-19) has led to further investigation into the role of platelets, and their precursor cell, the megakaryocyte, during disease course. Previously published post-mortem evaluations of patients who succumbed to Coronavirus Disease 2019 (COVID-19) have reported the presence of megakaryocytes in the cardiac microvasculature. Our series evaluated a cohort of autopsies performed on SARS-CoV-2 positive patients in 2020 (n = 36) and pre-pandemic autopsies performed in early 2020 (n = 12) and selected to represent comorbidities common in cases of severe COVID-19 in addition to infectious and non-infectious pulmonary disease and thromboembolic phenomena. Cases were assessed for the presence of cardiac megakaryocytes and correlate with the presence of pulmonary emboli and laboratory platelet parameters and inflammatory markers. Cardiac megakaryocytes were detected in 64% (23/36) of COVID-19 autopsies, and 40% (5/12) pre-pandemic autopsies, with averages of 1.77 and 0.84 megakaryocytes per cm2 , respectively. Within the COVID-19 cohort, autopsies with detected megakaryocytes had significantly higher platelet counts compared with cases throughout; other platelet parameters were not statistically significant between groups. Although studies have supported a role of platelets and megakaryocytes in the response to viral infections, including SARS-CoV-2, our findings suggest cardiac megakaryocytes may be representative of a non-specific inflammatory response and are frequent in, but not exclusive to, COVID-19 autopsies.