Hereditary thrombophilia as a possible risk factor for severe disease in COVID-19: a case series

The risk factors that modulate one's susceptibility for severe COVID-19 have been well documented. Despite this, hypercoagulability remains an often overlooked risk factor for severe disease for COVID-19. Because COVID-19 infection is a risk factor for hypercoagulability, a reasonable presumption/hypothesis is that patients with hereditary thrombophilia would be at a higher risk of thrombotic complications associated with COVID-19 infection.

This case report details two cases where previously unknown hereditary thrombophilias likely contributed to the mortality of COVID-19 patients.

The first COVID-19 patient's cause of death was pulmonary thromboemboli from deep vein thrombosis due to heterozygous MTHFR C667T and heterozygous PAI-1 4G/5G mutations. The second COVID-19 patient's cause of death was an acute myocardial infarct due to a coronary artery thrombosis in the setting of heterozygous MTHFR A1298C and homozygous PAI-1 4G/5G mutations. In each case, COVID-19 infection was also considered contributory to death.

The occurrence of these fatal thrombotic events in COVID-19 patients with hereditary thrombophilias raises questions as to whether this combination of thrombotic risk factors for hypercoagulability may have placed patients at a significant enough risk to experience these fatal thrombotic complications. Thus, while not sufficient alone to prove that SARS-CoV-2 patients with hereditary thrombophilias are at increased risk for thrombotic complications, these two cases indicate that further investigation is warranted into elucidating the relationship between thrombotic risk factors as it may identify an additional high-risk medical condition for COVID-19 and have important diagnostic and therapeutic ramifications.