Abstract 419: The Contribution of Neutrophil Extracellular Traps to Coagulopathy in Patients with COVID‐19 Related Vascular Thrombosis

Introduction Coronavirus disease 2019 is caused by severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) and has been associated with hypercoagulability and an increased incidence of thrombotic events as compared to other viral respiratory infections. In this study, we investigated the levels of neutrophil extracellular trap (NET) biomarkers and von Willebrand factor (VWF) to assess if these could be used to predict the occurrence of a thrombotic event in COVID‐19 patients. Methods We enrolled 202 patients hospitalized with symptomatic COVID‐19 infections. Of those, 104 patients did not experience any type of thrombotic events at any time preceding or during their hospitalization. These patients were compared to the other cohort of 98, who experienced thrombotic events before or during their hospitalization. 61 of the thrombotic event patients had the event after initial blood collection, so the predictive capacity of biomarkers in these patients was evaluated. Results We found that citrullinated histone H3 (ciH3) was the best predictive biomarker for thrombotic events in COVID‐19 regardless of age, sex, and race. We also found that disease severity was a significant predictor of occurrence of thrombotic event in most groups, including sex, race, and age. Thrombotic events are associated with a higher risk of mortality, specifically in COVID‐19 infection compared to other illnesses. Interestingly, in the age group less than 60, citH3 and neutrophil count were found to be significant predictors of thrombotic event occurrence but was not a significant predictor in the age group above 60. Conclusion Our findings of predictive capacity of citH3 and neutrophil count in patients younger than 60 could indicate newfound screening biomarkers for patients in this population. NETs may be involved in the thrombotic complications of COVID‐19, and these thrombotic events contribute to multi‐system organ failure and mortality in COVID‐19. These results may better inform treatment and prophylaxis of thrombotic events, with an emphasis in COVID‐19 and similar viral illnesses in the future to improve outcomes and reduce mortality. Understanding the biological etiologies of this disease and its thrombotic complications can improve therapeutic interventions to reduce the burden of thrombosis in patients with COVID‐19. These results may also be relevant to other infections and may inform potential mechanisms for treatment development for other respiratory diseases with thrombotic complications as well as thrombotic diseases such as Myocardial Infarctions and Ischemic stroke.