Therapeutic plasma exchange and dextran-sulfate plasma adsorption as extracorporeal treatments of extremely preterm preeclampsia with fetal growth restriction.

Aim: To evaluate effectiveness and safety of therapeutic plasma exchange (TPE) and dextran-sulfate plasma adsorption (DSA) for extracorporeal removal of soluble Fms-like tyrosine kinase-1 (sFlt-1) as part of expectant management of preeclampsia at extremely preterm gestational age.

Methods: Retrospective case series of six patients with preeclampsia at <28 weeks of gestation, treated with DSA or TPE. Laboratory results, clinical characteristics and neonatal outcomes were collected from charts and National Perinatal Information System.

Results: Fetal growth restriction (FGR) was diagnosed in all cases. Pregnancy was prolonged for a median of 14 (range 5-74) days from admission and 10 (3-73) days from first apheresis. A mixed effects model showed a decrease in sFlt-1 and sFlt-1/PlGF ratio during DSA/TPE (significant effect of time [before/after]), which was comparable between DSA and TPE (no effect of procedure type). Median absolute reduction in sFlt-1 was 42% (inter-quartile range [IQR] 13%-57%) during DSA and 34% (16%-40%) during TPE; for sFlt-1/PlGF ratio it was 29% (22%-36%) and 38% (29%-42%), respectively. All procedures were well tolerated by fetuses. Anaphylactoid reaction, often with angioedema, occurred in 4/6 patients undergoing DSA and was attributed to bradykinin activation. One patient developed wound hematoma after cesarean section, possibly attributed to depletion coagulopathy.

Conclusions: As potential novel treatment of early preeclampsia, a non-selective and widely available TPE was comparable to DSA regarding sFlt-1 reduction but was associated with fewer side-effects. Both seem to allow maternal stabilization and pregnancy prolongation even when early preeclampsia is complicated by FGR.