Thrombocytopenia in hydropic fetuses with parvovirus B19 infection: incidence, treatment and correlation with fetal B19 viral load

Abstract

Objective To examine (1) the incidence of fetal thrombocytopenia in hydropic fetuses with congenital B19 virus infection, (2) the effect of intrauterine platelet transfusions and (3) the correlation between fetal B19 viral load and severity of thrombocytopenia.Design Retrospective analysis of data from prospectively collected fetal blood samples.Setting Leiden University Medical Centre, the national centre for management of intrauterine fetal disease in the Netherlands.Population Thirty hydropic fetuses treated with intrauterine red blood cell and platelet transfusions for human B19 virus-induced severe fetal anaemia and thrombocytopenia over a 10-year period.Methods Fetal blood samples (n = 30) taken before and after intrauterine transfusion were investigated. No cases were excluded, and there was no loss to follow up.Main outcome measures Parameters recorded were gestational age, experienced fetal movements, gravidity and parity, severity of fetal hydrops, severity of fetal anaemia and thrombocytopenia and megakaryocyte and reticulocyte counts. Survival and procedureassociated complications were documented. Quantitative B19 viral load measurements were performed on all fetal samples.Results Forty-six percent of all hydropic fetuses showed severe thrombocytopenia. No antenatal intracerebral haemorrhage or procedure-associated bleeding occurred. Overall, survival was 77%. Platelet counts increased following platelet transfusion and decreased significantly following red blood cell transfusion alone. No correlation was found between fetal viral loads and platelet counts.Conclusion Thrombocytopenia was frequently encountered in fetal B19V infection, but fetal bleeding complications were not noted. Absence of a direct relationship between fetal B19 viral load and platelet counts suggests a temporal dissociation between these findings. Dilutional thrombocytopenia is frequently seen in the fetus following red blood cell transfusion alone. The clinical significance of this phenomenon is unclear. The risk of fluid overload by fetal platelet transfusion in a severely hydropic fetus should be weighed against the low incidence of fetal bleeding complications.

Selfness-nonselfness in designing an anti-B19 erythrovirus vaccine

“…4 In each epitope, low similarity pentapeptides are given in bold capital. 5 pentapeptide similarity is defined as number of pentapeptide occurrences (matches) in the human proteins.…”

Intrauterine Blood Transfusion: Current Indications and Associated Risks

“…In most cases, a single transfusion will lead to recovery. The presence of thrombocytopenia is frequently encountered in fetal parvovirus B19 infection and intrauterine platelet transfusion can be performed relatively safely, although the risk of fluid overload in the hydropic fetus should be weighed against the low incidence of fetal bleeding complications [25]. Perinatal survival after treatment with IUT for fetal anemia due to parvovirus ranges from 67 to 73% (table 1).…”

“…The use of fetal paralysis may prevent procedure-related fetal loss in 80% of the cases and thus improve the safety of the procedure [7,61]. Even more, prevention of volume overload by adjusting transfusion speed to gestational age, especially in young fetuses and/or hydropic fetuses, may improve outcome [25,62]. …”

Fetal Intracardiac Transfusions in Hydropic Fetuses with Severe Anemia

“…Single case studies have described a successful outcome in a severely anemic fetus secondary to parvovirus infection undergoing intracardiac transfusion [13]. In such pregnancies, with human parvovirus being the etiology of fetal anemia, even with fetal in-utero transfusion, survival is lower (60-77%) than reported for ‘Rhesus' disease, possibly due to associated significant anemia, thrombocytopenia, and impaired myocardial contractility [14,15]. It is our usual practice in women known to have severe red cell alloimmunization and a significant risk of the need for early in-utero transfusions to begin a combination of maternal intravenous immunoglobulin (IVIG) therapy and intraperitoneal transfusions (between 16-20 weeks) to delay the need for the first intravascular transfusion to >20 weeks of gestation [16].…”