According to a recent study, prophylactic fresh frozen plasma (FFP) may be used in patients with congenital thrombotic thrombocytopenic purpura (cTTP) during pregnancy to improve outcomes. However, pregnancy and delivery may be challenging even with this treatment. The study results were published in the Journal of Thrombosis and Haemostasis.
In patients with cTTP, pregnancy may trigger disease episodes, which have the potential to be fatal, the study investigators explained in their report. FFP can be a source of ADAMTS13 in patients with this condition that involves a deficiency in this enzyme.
In this retrospective study of pregnancy outcomes, patients who had thrombotic microangiopathy were identified from a registry in Japan. From a pool of 1516 patients with this condition, the researchers suspected 65 to have cTTP based on low ADAMTS13 activity (under 10% of normal without ADAMTS13 inhibitors). Diagnoses were confirmed by genetic analyses.
Pregnancy outcomes were compared in 2 groups of patients: those who became pregnant after cTTP diagnosis was confirmed (group 1) and those who became pregnant before cTTP was confirmed (group 2). ADAMTS13 activity was monitored throughout pregnancies in group 1.
A total of 60 patients had confirmed cTTP, among whom 21 were female, with a total of 38 pregnancies identified. Group 1 included 12 pregnancies and group 2 included 26 pregnancies.
Prophylactic FFP was given with 10 pregnancies in patients from group 1 for replenishment of ADAMTS13, and as test infusions with 3 pregnancies in patients from group 2. Group 1 pregnancies usually involved FFP infusion dosages that were above 5 mL/kg/week by 20 weeks.
Live births occurred in 9 of the group 1 pregnancies and 13 of the group 2 pregnancies. The fetal survival rate in group 1 was significantly higher than the rate for group 2 (P =.016). Fetal survival was also significantly higher among pregnancies in which FFP was used (P =.009). The most pronounced differences in fetal survival occurred after 20 weeks of gestation.
In 3 cases in group 1, emergency cesarean sections were required, 2 of which occurred in the same patient. In group 1, deliveries occurred prior to 36 weeks of gestation in 5 cases, while the other 7 pregnancies resulted in deliveries at or beyond 37 weeks.
Mild to moderate allergic reactions were common in association with FFP infusions in this study, but these were reported to be tolerable with treatment consisting of steroids and/or antiallergic agents.
The researchers concluded that FFP may aid with favorable pregnancy outcomes in patients with cTTP, but its effectiveness can be limited in some cases, such as with patients experiencing uncontrolled TTP.
Disclosures: Some authors have declared affiliations with or received grant support from the pharmaceutical industry. Please refer to the original study for a full list of disclosures.
Sakai K, Fujimura Y, Nagata Y, et al. Success and limitations of plasma treatment in pregnant women with congenital thrombotic thrombocytopenic purpura. J Thromb Haemost. 2020;18(11):2929-2941. doi:10.1111/jth.15064