Feto‐maternal alloimmune thrombocytopenia: antenatal therapy with IvIgG and steroids — more questions than answers

Abstract

The optimal antenatal therapy for fetal thrombocytopenia has not been determined. We analysed 37 cases managed by maternal therapy and observed a successful outcome of maternal treatment in 26% of IvIgG cases and in 10% of steroid-treated cases. The significance of a plateau of the fetal platelet counts during pregnancy, 41% of IvIgG cases and 20%, of cases treated with steroids, is uncertain. It may indicate a stabilization of thrombocytopenia, hence a beneficial effect of therapy, or the natural course of the platelet count in a low-risk pregnancy. Overall outcome was unpredictable, but amongst the therapy failures there were proportionally more severely affected siblings. Further multicentre studies are necessary to establish the optimal antenatal management of high-risk pregnancies.

Antenatal treatment of fetal alloimmune thrombocytopenia: a current perspective

“…4 This approach of providing IVIG-based medical therapy administered to the mother to increase the fetal platelet count has since been extensively investigated in hundreds of maternal-fetal pairs. 5 The efficacy of IVIG-based therapy has been supported by numerous studies [6][7][8][9][10][11][12][13][14][15][16] (Table 1A) but not by others [17][18][19] (Table 1B). The studies presented in Tables 1A and 1B surprisingly report virtually identical percentages of cases of intracranial hemorrhage: 2.7% versus 2.9%, respectively.…”

“…Since fetuses with alloimmune thrombocytopenia are vulnerable to compromised hemostasis due to severe thrombocytopenia, impaired platelet function, and endothelial dysfunction; the risks of fetal blood sampling are considerable and well-documented. [10][11][12]14,15,17,18,22,23 Birchall and colleagues from Europe reported a number of procedure-related complications, including exsanguination and emergency Cesarean deliveries attributed to infection, needle dislodgement, severe fetal bradycardia, cord spasm and thrombosis. 11 For these reasons, fetal blood sampling is generally coupled with intra-uterine platelet transfusion if platelet counts are low (e.g., < 50¥10 9 /L).…”

“…The current focus on non-invasive approaches 9,13,15,23 serves both as a response to the high complication rate of invasive strategies [10][11][12]14,15,17,18,22,23 and as a testament to the efficacy of maternal IVIG-based treatment. In one study Yinon et al suggested that IVIG without fetal blood sampling is safe and effective in women who, like the subjects featured in the study conducted by Giers et al, 19 lacked a history of fetal or neonatal intracranial hemorrhage in a previous child.…”

Prediction of the fetal status in noninvasive management of alloimmune thrombocytopenia

“…The first antenatal management for subsequent incompatible fetuses was in utero platelet transfusions in the preterm period 5 and then maternal administration of intravenous immunoglobulin (IVIG) during pregnancy. [6][7][8] For ethical reasons, no double-blind study has been performed. All these nonrandomized studies were in favor of IVIG, and maternal therapy with IVIG is nowadays considered as the first-line treatment.…”

Developing recombinant HPA-1a–specific antibodies with abrogated Fcγ receptor binding for the treatment of fetomaternal alloimmune thrombocytopenia

“…Intrauterine transfusions (IUTs) of HPA-1a -platelets are a logistical challenge (14), and the risk of fetal loss is up to 15% (15)(16)(17)(18). Several trials have shown the benefit of intravenous immunoglobulin (IVIG) therapy, but in 50% of patients with severe disease (ICH in the previous pregnancy or an initial fetal platelet count of fewer than 20 × 10 9 /l), IVIG therapy does not achieve a safe fetal platelet count (19)(20)(21)(22)(23). Although IVIG therapy may reduce the incidence of ICH in this high-risk group without a rise in platelet count (24), ICHs still occur in some cases (21,25,26).…”