Coronavirus disease 2019 (COVID-19) or severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), a novel coronavirus strain disease, has recently emerged in China and rapidly spread worldwide. This novel strain is highly transmittable and severe disease has been reported in up to 16% of hospitalized cases. More than 600,000 cases have been confirmed and the number of deaths is constantly increasing. COVID-19 hospitalized patients, especially those suffering from severe respiratory or systemic manifestations, fall under the spectrum of the acutely ill medical population, which is at increased venous thromboembolism risk. Thrombotic complications seem to emerge as an important issue in patients infected with COVID-19. Preliminary reports on COVID-19 patients’ clinical and laboratory findings include thrombocytopenia, elevated D-dimer, prolonged prothrombin time, and disseminated intravascular coagulation. As the pandemic is spreading and the whole picture is yet unknown, we highlight the importance of coagulation disorders in COVID-19 infected patients and review relevant data of previous coronavirus epidemics caused by the severe acute respiratory syndrome coronavirus 1 (SARS-CoV-1) and the Middle East Respiratory Syndrome coronavirus (MERS-CoV).

COVID-19 and coagulation disorders

A novel coronavirus strain disease, Coronavirus disease 2019 (COVID-19) or severe acute respiratory syndrome coronavirus 2 (SARSCoV-2), has recently emerged in Wuhan, China and rapidly spread throughout China and subsequently worldwide [1,2]. Currently, more than 600,000 cases have been diagnosed and over 25,000 infected people have died [3]. Patients usually present with fever (> 80%), cough (> 60%), and myalgia or fatigue (> 40%) [1,4]. Males are more commonly affected (∼۶۰% of cases) with a median age of approximately 50 years [1,4,5]. The complete spectrum of presentations and complications associated with COVID-19 is not fully elucidated. Clinical manifestations range from asymptomatic or very mild to severe illness, sepsis and death. While the current state of evidence suggests that most COVID-19 illness is mild, the study by Guan et al. suggests severe illness occurs in 16% of cases [4,6]. As the pandemic is still in progression, with an incomplete picture and potential treatments in preliminary stages only, we sought to review the available literature relevant to coagulation disorders in patients infected by the severe acute respiratory syndrome coronavirus 1 (SARS-CoV-1) and the Middle East Respiratory Syndrome coronavirus (MERS-CoV) to raise awareness about these potential complications in patients with COVID-19. Thrombotic complications seem to emerge as an important issue in patients with COVID-19. Preliminary reports on COVID-19 pandemic outcomes have shown that infected patients commonly develop thrombocytopenia (36.2%) and may have elevated D-dimer (46.4%) [4], while these rates are even higher in patients with severe COVID-19 disease (57.7% and 59.6%, respectively) [4]. Emerging data support that patients infected by this novel coronavirus are at risk of developing disseminated intravascular coagulation (DIC) [4,7,8].