Skin manifestations as potential symptoms of diffuse vascular injury in critical COVID-19 patients

As a respiratory viral infection caused by a novel coronavirus, COVID-19 became rapidly pandemic within a few months. Despite the wide range of manifestations and organ involvement in COVID-19 patients, the exact pathogenesis of severe and fatal types of COVID-19 and causes involved with the individual base of the disease is not yet understood. Several studies have reported clinical, laboratory, and histopathological data in favor of vascular injury in multiple organs of critically ill patients with COVID-19 as a result of hyperactive immune response, inflammation, and cytokine storm. Also, both clinical and histopathological evidence points to such vascular involvements in the skin. Given the ease of clinical examinations and skin biopsy and the lower risks of transmission of COVID-19 to healthcare workers, the present review article was conducted to investigate the vascular skin manifestations of COVID-19 patients clinically and/or histopathologically as helpful clues for better understanding the pathogenesis and predicting the prognosis of the disease, especially in severe cases.