Abstract Number: PB1894
Meeting: ISTH 2020 Congress
Theme: Thrombotic Microangiopathies » Antiphospholipid Syndrome
Background: Late pregnancy complications are still frequent in treated pregnant women with the obstetric antiphospholipid syndrome (oAPS). Available data strongly suggest ADAMTS13 autoantibodies and ADAMTS13 dysfunction globally occurring in APS, particularly in oAPS during preeclampsia (PEcl) and hemolysis, elevated liver enzymes and low platelet count (HELLP) syndrome.
Aims: To study ADAMTS13 and ADAMTS13 antibodies and their prognostic value in newly pregnant oAPS women.
Methods: The study was performed in the 513 oAPS women included into the NOH-APS cohort, who began a new pregnancy treated with enoxaparin 40 mg + aspirin 100 mg daily (Blood 2014; 123: 404-13). Frozen plasma aliquotes obtained just before the beginning of LMWH injections were tested for ADAMTS13 activity and antigen, ADAMTS13 antibodies (ELISA, Technoclone, Vienna, Austria) , PGF and sFlt1 concentrations (ELISA, R&D Systems, Abingdon, UK) blindly from pregnancy outcomes. The relationship between biological data and the occurrence of placenta mediated complications was investigated through univariate then multivariate logistic regression analysis.
Results: Women who developed PEcl had lower ADAMTS13 activities, higher ADAMTS13 antibodies and sFlt1 concentrations, categorization into tiertiles showing a concentration-effect relationship on the clinical risk. This culminated in severe PEcl cases, in early-onset PEcl cases
(< 34 weeks), in eclampsia cases and in HELLP syndrome cases. The final models evidenced high concentrations of ADAMTS13 antibodies and of sFlt1, and low concentrations of ADAMTS activities, to be independent risk factors for the occurrence of early-onset PEcl, also of HELLP syndrome, together with a triple positivity for antiphospholipid antibodies.
Conclusions: In newly pregnant women with oAPS conventionally treated, the early evaluation of ADAMTS13 can help to indicate the clinical risk of late complications with high morbidity potential. ADAMTS13 might be a clinically-relevant therapeutic target.
To cite this abstract in AMA style:
Bitsadze V, Bouvier S, Khizroeva J, Nouvellon E, Mousty E, Mercier E, Letouzey V, Makatsariya A, Gris J-. Obstetric Antiphospholipid Syndrome: ADAMTS-13 Tested at Pregnancy Diagnosis Is Associated with the Occurrence of Early-Onset Pre-Eclampsia Despite Treatment [abstract]. Res Pract Thromb Haemost. 2020; 4 (Suppl 1). https://abstracts.isth.org/abstract/obstetric-antiphospholipid-syndrome-adamts-13-tested-at-pregnancy-diagnosis-is-associated-with-the-occurrence-of-early-onset-pre-eclampsia-despite-treatment/. Accessed September 29, 2023.« Back to ISTH 2020 Congress
ISTH Congress Abstracts - https://abstracts.isth.org/abstract/obstetric-antiphospholipid-syndrome-adamts-13-tested-at-pregnancy-diagnosis-is-associated-with-the-occurrence-of-early-onset-pre-eclampsia-despite-treatment/