Читать книгу Protocols for High-Risk Pregnancies - Группа авторов - Страница 152

This includes women with a prior fetus or newborn with thrombocytopenia or ICH of unproven etiology and evidence of a parental HPA antigen mismatch, but no identification of a specific causative anti‐HPA antibody in maternal serum. As mentioned above, while FNAIT is unlikely in this case, the diagnosis cannot be entirely excluded, especially if maternal FNAIT screening occurred months after the affected index pregnancy. Treatment is not recommended in these cases but repeat maternal antibody screening may be considered on an every‐trimester basis (i.e., at 10–12 weeks, 22–24 weeks, and 30–32 weeks of gestational age) in a subsequent at‐risk pregnancy. Should specific anti‐HPA antibodies be detected, the patient should be triaged to the medium‐risk category and treated accordingly. In cases without parental HPA antigenic mismatch, a rare incompatibility undetectable by conventional screening methods is theoretically possible. In this case, a single antibody screen involving cross‐matching of maternal and paternal platelets at around 20–24 weeks may be considered. With a positive antibody screen for platelet‐specific antibodies, the patient should be escalated to the medium‐risk group, and treatment started.