Generation of potentially inhibitory autoantibodies to ADAMTS13 in coronavirus disease 2019

Dynamic Assessment of Plasma von Willebrand Factor and ADAMTS13 Predicts Mortality in Hospitalized Patients with SARS-CoV-2 Infection

BACKGROUND

Plasma levels of von Willebrand factor (VWF) are significantly elevated in patients with coronavirus disease 2019 (COVID-19). However, dynamic changes and prognostic value of this biomarker in hospitalized patients with COVID-19 have not been determined.

METHODS

A total of 124 patients infected with SARS-CoV-2 were prospectively recruited for the study. Serial blood samples were obtained at the time of admission (D1), 3-4 days following standard-care treatments (D2), and 1-2 days prior to discharge or any time collected prior to death (D3). Plasma VWF antigen, ADAMTS13 antigen, and ADAMTS13 proteolytic activity, as well as the ratio of VWF/ADAMTS13 were determined, followed by various statistical analyses.

RESULTS

On admission, plasma levels of VWF in COVID-19 patients were significantly elevated compared with those in the healthy controls, but no statistical significance was detected among patients with different disease severity. Plasma ADAMTS13 activity but not its antigen levels were significantly lower in patients with severe or critical COVID-19 compared with that in other patient groups. Interestingly, the ratios of plasma VWF antigen to ADAMTS13 antigen were significantly higher in patients with severe or critical COVID-19 than in those with mild to moderate disease. More importantly, plasma levels of VWF and the ratios of VWF/ADAMTS13 were persistently elevated in patients with COVID-19 throughout hospitalization. Kaplan-Meier and Cox proportional hazard regression analyses demonstrated that an increased plasma level of VWF or ratio of VWF/ADAMTS13 at D2 and D3 was associated with an increased mortality rate.

CONCLUSIONS

Persistent endotheliopathy, marked by the elevated levels of plasma VWF or VWF/ADAMTS13 ratio, is present in all hospitalized patients following SARS-CoV-2 infection, which is strongly associated with mortality.

Impact of Concomitant Thrombotic Thrombocytopenic Purpura on COVID-19 Mortality and Morbidity: A Nationwide Inpatient Sample Analysis

Utilizing the comprehensive Nationwide Inpatient Sample (NIS) database, we examined the impact of thrombotic thrombocytopenic purpura (TTP) on the outcomes of patients with coronavirus disease-19 (COVID-19), emphasizing the potential role of the ADAMTS13 enzyme in disease pathogenesis and evolution. We analyzed extensive data from the NIS database using STATA v.14.2 and accounted for potential confounders using multivariate regression analysis to uphold the validity and reliability of the study. Among 1 050 045 adult patients hospitalized with COVID-19, only 300 (0.03%) developed TTP. These patients were younger (mean age 57.47 vs 64.74, P < .01) and exhibited a higher prevalence of preexisting conditions, such as congestive heart failure (13.33% vs 16.82%, P value not provided) and end-stage renal disease (3.33% vs 3.69%, P value not provided). On multivariate regression analysis, COVID-19 patients with concomitant TTP demonstrated a significant increase in mortality (adjusted odds ratio [AOR] 3.99, P < .01), venous thromboembolism (AOR 3.33, P < .01), acute kidney injury (AOR 7.36, P < .01), gastrointestinal bleeding (AOR 10.75, P < .01), intensive care unit admission (AOR 14.42, P < .01), length of hospital stay (17.42 days, P < .01), and total hospitalization charges ($298 476, P < .01). Thrombotic thrombocytopenic purpura in COVID-19 patients elevates the risk of mortality and complications, likely driven by the thrombotic nature of TTP. Our data underline the potential significance of ADAMTS13 in COVID-19 and TTP pathophysiology, suggesting its possible role as a therapeutic target.