Hemostatic system and COVID-19 crosstalk: A review of the available evidence

Abstract

Since the discovery of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and its resultant coronavirus disease 2019 (COVID-19) pandemic, respiratory manifestations have been the mainstay of clinical diagnosis, laboratory evaluations, and radiological investigations. As time passed, other pathological aspects of SARS-CoV-2 have been revealed. Various hemostatic abnormalities have been reported since the rise of the pandemic, which was sometimes superficial, transient, or fatal. Mild thrombocytopenia, thrombocytosis, venous, arterial thromboembolism, and disseminated intravascular coagulation are among the many hemostatic events associated with COVID-19. Venous thromboembolism necessitating therapeutic doses of anticoagulants is more frequently seen in severe cases of COVID-19, especially in patients admitted to intensive care units. Hemorrhagic complications rarely arise in COVID-19 patients either due to a hemostatic imbalance resulting from severe disease or as a complication of over anticoagulation. Although the pathogenesis of coagulation disturbance in SARS-CoV-2 infection is not yet understood, professional societies recommend prophylactic antithrombotic therapy in severe cases, especially in the presence of abnormal coagulation indices. The review article discusses the various available evidence on coagulation disorders, management strategies, outcomes, and prognosis associated with COVID-19 coagulopathy, which raises awareness about the importance of anticoagulation therapy for COVID-19 patients to guard against possible thromboembolic events.

Keywords: SARS-CoV-2; COVID-19; Thrombosis; Pulmonary embolism; Disseminated intravascular coagulation

Core Tip: The pathogenesis of hypercoagulable state and thrombosis related to coronavirus disease 2019 (COVID-19) is unclear. Evidence on endothelial cell injury by direct infection of severe acute respiratory syndrome coronavirus 2 is increasing. Histologic and immunohistochemistry examination of lung autopsies and/or the skin of patients who have died of severe COVID-19 has shown microvascular injury and thrombosis, consistent with intensive and generalized activation of both alternative and lectin-based pathways of complement.