Lung pathology in COVID-19: A systematic review

Sparse literature is available regarding autopsy findings of coronavirus disease 2019 (COVID-19) despite high mortality due to its highly contagious nature and lack of robust infrastructure for appropriate handling of the infected cases. Based on clinical findings and various diagnostic tests, it is evident that it holds the potential to affect multiple organ systems of the body preferably lungs and immune and coagulation systems. Cytokine storm-induced thrombotic complication such as disseminated intravascular coagulation is a significant feature in severe cases of COVID-19. This review captures the current information on lung histopathology in COVID-19 infection and severe respiratory failure. In COVID-19, lungs are affected bilaterally, become edematous and red/tan mottled to maroon in color with firm consistency. Distinct parenchymal changes, firm thrombi in the peripheral pulmonary vessels along with diffuse alveolar damage, have been the most consistent feature of COVID-19-related lung pathology. Electron microscopy has also been used to demonstrate viral particles.