Abstract Number: OC 51.2
Meeting: ISTH 2022 Congress
Theme: Women’s Health » Pregnancy and Pregnancy Complications
Background: There is evidence, some conflicting, of changes in the VWF/ADAMTS13 axis, and also in the complement system, in preeclampsia and HELLP syndrome. Other obstetric complications are less studied in this regard.
Aims: To assess changes in VWF, ADAMTS13 and complement in preeclampsia, HELLP syndrome, fetal growth restriction (unexplained or uteroplacental), and new onset thrombocytopenia ( < 75×109/L), compared to normal pregnancies.
Methods: Pregnant women with a current or previous history of the obstetric complications of interest were recruited at a regional centre, in addition to gestational age-matched normal pregnant controls. ADAMTS13 activity, VWF antigen and activity, CH50, and sC5b-9 were measured in blood samples taken at recruitment. Clinical data was collected. Informed consent and regional ethics committee approval (18/NW/0552) were obtained. Data is summarised as median (range). Mann-Whitney was used to compare groups (with significance level P < 0.05).
Results: 128 cases were analyzed. Comparing preeclampsia/HELLP (Nf42) with normal pregnancy (Nf48) (Table 1), ADAMTS13 activity was significantly lower in preeclampsia, VWF antigen and activity were significantly higher, and the VWF antigen:ADAMTS13 ratio was even higher (3.7 (1.9-6.5) vs 2.1 (0.9-4.7), P < 0.0001). sC5b-9 was higher in preeclampsia/HELLP than normal pregnancy (268 (162-628) vs 189 (110-290), P < 0.0001), but there was no change in CH50. Abnormalities were greater in cases with features of HELLP (Nf9). Similar changes were not observed in fetal growth restriction (Nf13), thrombocytopenia (Nf10), or in pregnant women with a history of preeclampsia (Nf15) (Figure 1). The odds of VWF Ag:ADAMTS13 ratio > 2 was 31.9 times higher in preeclampsia than normal pregnancy (95% CI 4.8-338.4), while the odds of sC5b-9>180ng/ml was 11.0 times higher (2.6-49.7).
Conclusion(s): There is marked elevation in VWF levels, VWF antigen:ADAMTS13 ratio, and sC5b-9 in preeclampsia/HELLP compared to normal pregnancies and certain other obstetric complications. This may result from endothelial activation, and may have potential therapeutically and diagnostically.
To cite this abstract in AMA style:
Neave L, Thomas M, de Groot R, Doyle A, David A, Maksym K, Whitten M, Scully M. Changes in VWF, ADAMTS13, and Complement in Preeclampsia, HELLP syndrome and Other Obstetric Complications: a Single Centre Observational Study. [abstract]. https://abstracts.isth.org/abstract/changes-in-vwf-adamts13-and-complement-in-preeclampsia-hellp-syndrome-and-other-obstetric-complications-a-single-centre-observational-study/. Accessed April 18, 2024.« Back to ISTH 2022 Congress
ISTH Congress Abstracts - https://abstracts.isth.org/abstract/changes-in-vwf-adamts13-and-complement-in-preeclampsia-hellp-syndrome-and-other-obstetric-complications-a-single-centre-observational-study/