Is COVID-19 an Independent Risk Factor for Heparin-Induced Thrombocytopenia?

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causes a viral respiratory illness initially described in Wuhan, China, and was declared a pandemic by World Health Organization (WHO) in 2020, and the disease is named coronavirus disease (COVID-19). SARS-CoV2 is known to cause fever, cough, fatigue, and acute respiratory distress syndrome. As more patients become infected, extrapulmonary manifestations came to rise and hypercoagulability is one among those. COVID-19 could predispose patients to both venous and arterial thromboembolic events which are commonly treated with unfractionated heparin or low molecular weight heparin (LMWH). The treatment of patients who develop heparin-induced thrombocytopenia (HIT) while being treated with heparin or LMWH for COVID-induced thromboembolic complications is challenging. We describe a patient admitted to the hospital with COVID-19 pneumonia, found to have a cerebrovascular event treated with unfractionated heparin. She also received therapeutic LMWH for anticoagulation on day 1 of presentation due to atrial fibrillation. She was diagnosed with HIT and was found to have a pulmonary embolism, aortic arch mural thrombus, and arterial thrombi in the lower extremities. As more recent studies showed HIT antibodies in COVID-19 patients who are naive for heparin-based products, COVID-19 may be an independent risk factor for the development of HIT. The role of COVID-19 in the development of HIT is uncertain. High vigilance is required to diagnose and initiate treatment for HIT early in the disease course as it can be life-threatening.