Abstract Number: PB0743
Meeting: ISTH 2021 Congress
Theme: Role of Hemostatic System in Cancer, Inflammation and Immunity » Infection and Hemostatic Factors
Background: An increased incidence of venous thrombo-embolism (VTE) has been observed in human immunodeficiency virus (HIV) infected pregnant women in the era of antiretroviral therapy (ART). The extent to which endothelial activation contributes among virologically- suppressed HIV-infected pregnant women has not been studied. The plasma ratio of von Willebrand factor (VWF) propeptide to VWF antigen, which declines in normal pregnancy, has been identified as a useful marker of endothelial activation.
Aims: To assess the VWF propeptide to antigen ratio in all three trimesters of pregnancy and its relationship with HIV viral load (VL) and ADAMTS13
Methods: A cross-sectional analysis was performed in 89 HIV-infected virologically-suppressed patients on ART for 5 [7] years, 63 HIV-infected patients with VL >50 copies/ml and 85 matched HIV-uninfected women. Testing was measured in the first (6-12 weeks), second (13-26 weeks) and third trimesters (27-39 weeks). The study protocol was approved by the ethics committee of the University of the Witwatersrand (M-181018).
Results: 
Comparison of von Willebrand Factor associated parameters between HIV-uninfected, HIV-infected with virological-suppression and HIV-infected with VL >50 copies/ml study groups
Elevated measurements of VWF propeptide to antigen ratio were observed, in the first, second and third trimesters, in the HIV-infected group with VL >50 copies/ml (1.9 ± 0.9, 1.7 ± 0.9, 1.6 ± 1.1) and the HIV-infected virologically-suppressed group (1.7 ± 0.7, 1.7 ± 0.4, 1.6 ± 0.5) as compared to the HIV-uninfected group (1.4 ± 0.6, 1.3 ± 0.4, 1.2 ± 0.3, p<0.05). This was associated with a modest reduction in ADAMTS13 activity per trimester in the HIV-infected group with VL >50 copies/ml (53.6 ± 23.3; 64.6 ± 29.2; 63.4 ± 26.5) and the HIV-infected virologically-suppressed group (55.1 ± 25.2; 62.7 ± 30.1; 71.5 ± 29.9 %) as compared to the HIV-uninfected group (84.5 ± 31.4; 92.9 ± 27.3; 96.1 ± 24.4, p<0.001). Antibodies directed against ADAMTS13 were not significantly increased in HIV infected pregnancies (p<0.05). There were no VTE cases in pregnancy or up to six-weeks postpartum.
Conclusions: HIV-infected virologically suppressed pregnant patients show persistent endothelial activation.
To cite this abstract in AMA style:
Schapkaitz E, Libhaber E, Jacobson B, Meiring M, Büller H. Von Willebrand Factor Propeptide to Antigen Ratio: Evidence of Endothelial Activation in HIV Infected Pregnancy [abstract]. Res Pract Thromb Haemost. 2021; 5 (Suppl 2). https://abstracts.isth.org/abstract/von-willebrand-factor-propeptide-to-antigen-ratio-evidence-of-endothelial-activation-in-hiv-infected-pregnancy/. Accessed June 25, 2022.« Back to ISTH 2021 Congress
ISTH Congress Abstracts - https://abstracts.isth.org/abstract/von-willebrand-factor-propeptide-to-antigen-ratio-evidence-of-endothelial-activation-in-hiv-infected-pregnancy/