Protein S Deficiency and COVID-19: A Brutal Combination Leading to Acute Submassive Bilateral Pulmonary Embolism

Protein S deficiency is a form of inherited thrombophilia that occurs due to low levels of or improper function of protein S. The role of protein S is to inactivate procoagulant factors, and a deficiency results in an increased risk of thrombotic events. The coronavirus disease 2019 (COVID-19) infection has also been studied to increase the risk of venous thromboembolism (VTE) due to an interplay of several mechanisms. However, the risk of VTE in patients affected by both of these disease processes simultaneously has not been thoroughly studied, and so recommendations regarding routine screening and prophylaxis of VTE have also not been established. We discuss the case of a 46-year-old woman with a past history of protein S deficiency and a recent COVID-19 infection who presented with complaints of shortness of breath. Upon examination, she was found to be hypoxic and tachycardic. A computed tomography angiography of the chest was done and revealed acute submassive bilateral pulmonary embolism with right heart strain and pulmonary infarcts. She was initially treated with intravenous heparin and later transitioned to oral anticoagulation for a minimum of six months.