High-dose intravenous immunoglobulin as the sole prenatal treatment for severe Rh immunization

Intravenous immunoglobulin for the treatment of severe maternal alloimmunization: individual patient data meta-analysis

OBJECTIVE

This study aimed to investigate the outcomes associated with the administration of maternal intravenous immunoglobulin in high-risk red blood cell-alloimmunized pregnancies.

DATA SOURCES

Medline, Embase, and Cochrane Library were systematically searched until June 2023.

STUDY ELIGIBILITY CRITERIA

This review included studies reporting on pregnancies with severe red blood cell alloimmunization, defined as either a previous fetal or neonatal death or the need for intrauterine transfusion before 24 weeks of gestation in the previous pregnancy as a result of hemolytic disease of the fetus and newborn.

METHODS

Cases were pregnancies that received intravenous immunoglobulin, whereas controls did not. Individual patient data meta-analysis was performed using the Bayesian framework.

RESULTS

Individual patient data analysis included 8 studies consisting of 97 cases and 97 controls. Intravenous immunoglobulin was associated with prolonged delta gestational age at the first intrauterine transfusion (gestational age of current pregnancy - gestational age at previous pregnancy) (mean difference, 3.19 weeks; 95% credible interval, 1.28-5.05), prolonged gestational age at the first intrauterine transfusion (mean difference, 1.32 weeks; 95% credible interval, 0.08-2.50), reduced risk of fetal hydrops at the time of first intrauterine transfusion (incidence rate ratio, 0.19; 95% credible interval, 0.07-0.45), reduced risk of fetal demise (incidence rate ratio, 0.23; 95% credible interval, 0.10-0.47), higher chances of live birth at ≥28 weeks (incidence rate ratio, 1.88; 95% credible interval, 1.31-2.69;), higher chances of live birth at ≥32 weeks (incidence rate ratio, 1.93; 95% credible interval, 1.32-2.83), and higher chances of survival at birth (incidence rate ratio, 1.82; 95% credible interval, 1.30-2.61). There was no substantial difference in the number of intrauterine transfusions, hemoglobin level at birth, bilirubin level at birth, or survival at hospital discharge for live births.

CONCLUSION

Intravenous immunoglobulin treatment in pregnancies at risk of severe early hemolytic disease of the fetus and newborn seems to have a clinically relevant beneficial effect on the course and severity of the disease.

Update on the Use of Intravenous Immunoglobulin in Pregnancy

Intravenous immunoglobulin (IVIG) was first administered to humans in the 1980s. The mechanism of action of IVIG is still a subject of debate but the pharmacokinetics have been well characterized, albeit outside of pregnancy. IVIG has been used in pregnancy to treat several nonobstetrical and obstetrical-related conditions. However, current evidence suggests that IVIG use during pregnancy can be recommended for 1) in utero diagnosis of neonatal alloimmune thrombocytopenia; 2) gestational alloimmune liver disease; 3) hemolytic disease of the fetus and newborn for early-onset severe intrauterine disease; 4) antiphospholipid syndrome (APS) when refractory to or contraindicated to standard treatment, or in catastrophic antiphospholipid syndrome; and 5) immune thrombocytopenia when standard treatment is ineffective or rapid increase of platelet counts is needed. All recommendations are based on case series and cohort studies without randomized trials usually because of the rare prevalence of the conditions, the high incidence of adverse outcomes if left untreated, and ethical concerns. In contrast, IVIG therapy cannot be recommended for recurrent pregnancy loss, and the use of IVIG in subgroups of those with recurrent pregnancy loss requires further investigations. For non-obstetrical-related conditions, we recommend using IVIG as indicated for nonpregnant patients. In conclusion, the use of IVIG during pregnancy is an effective treatment in some obstetrical-related conditions with rare serious maternal side effects. However, the precise mechanisms of action and the long-term immunologic effects on the fetus and neonate are poorly understood and merit further investigations.

Clinical consequences of the extremely rare anti-PP1Pk isoantibodies in pregnancy: a case series and review of the literature

BACKGROUND

The absence of the red cell antigens P, P1 and P^k , known as 'p', represents an extremely rare red cell phenotype. Individuals with this phenotype spontaneously form anti-PP1P^k isoantibodies, associated with severe haemolytic transfusion reactions, recurrent spontaneous abortion and haemolytic disease of the fetus and newborn (HDFN).

METHODS

We report a series of four successful pregnancies in three women with anti-PP1P^k isoantibodies, one complicated by HDFN, another by intrauterine growth restriction, all managed supportively. We also review the literature regarding the management of pregnancy involving anti-PP1P^k isoimmunization.

RESULTS

The literature surrounding anti-PP1P^k in pregnancy is limited to a very small number of case reports. The majority report management with therapeutic plasma exchange (TPE) with or without intravenous immunoglobulin. The relationship between titre and risk of pregnancy loss remains unclear, though a history of recurrent pregnancy loss appears important. Although a positive cord blood direct antiglobulin test is frequently noted, clinically significant HDFN appears uncommon, though possible.

CONCLUSION

Early initiation of TPE in high risk patients should be strongly considered. If possible, pregnancies should be managed in a high-risk obstetric or maternal fetal medicine service. The fetus should be monitored closely with interval fetal ultrasound and middle cerebral artery peak systolic volume Doppler to screen for fetal anaemia. Timely sourcing of compatible blood products is likely to be highly challenging, and both directed and autologous donation should be contemplated where appropriate. The International Red Cell Donor Panel may also provide access to compatible products.

Current perspective and scope of fetal therapy: part 2

Fetal therapy has been defined as any therapeutic intervention either invasive or noninvasive for correcting or treating any fetal malformation or condition. Invasive fetal therapy have its own set of maternal and fetal complications and invasive approach is not feasible in many of fetal conditions that are candidate for fetal therapy. Many such fetal conditions have been treated successfully by medical or noninvasive management. In medical fetal therapy, mothers are treated with medications which are transferred to fetus through placenta and exert positive effect on the fetus, thus avoiding complications that are seen secondary to invasive fetal therapy. The fetal conditions that have been managed with medical therapy includes fetal and neonatal alloimmune thrombocytopenia, neural tube defect, congenital adrenal hyperplasia, perinatal infections, respiratory distress syndrome, inborn error of metabolism, and congenital cystic adenomatoid malformation. This review will cover the medical or noninvasive aspect of fetal therapy and will highlight the progress made in the management of these fetal conditions.

Current perspective and scope of fetal therapy: part 1

Fetal therapy term has been described for any therapeutic intervention either invasive or noninvasive for the purpose of correcting or treating any fetal malformation or condition. Fetal therapy is a rapidly evolving specialty and has gained pace in last two decades and now fetal intervention is being tried in many malformations with rate of success varying with the type of different fetal conditions. The advances in imaging techniques have allowed fetal medicine persons to make earlier and accurate diagnosis of numerous fetal anomalies. Still many fetal anomalies are managed postnatally because the fetal outcomes have not changed significantly with the use of fetal therapy and this approach avoids unnecessary maternal risk secondary to inutero intervention. The short-term maternal risk associated with fetal surgery includes preterm labor, premature rupture of membranes, uterine wall bleeding, chorioamniotic separation, placental abruption, chorioamnionitis, and anesthesia risk. Whereas, maternal long-term complications include risk of infertility, uterine rupture, and need for cesarean section in future pregnancies. The decision for invasive fetal therapy should be taken after discussion with parents about the various aspects like postnatal fetal outcome without fetal intervention, possible outcome if the fetal intervention is done, available postnatal intervention for the fetal condition, and possible short-term and long-term maternal complications. The center where fetal intervention is done should have facility of multi-disciplinary team to manage both maternal and fetal complications. The major issues in the development of fetal surgery include selection of patient for intervention, crafting effective fetal surgical skills, requirement of regular fetal and uterine monitoring, effective tocolysis, and minimizing fetal and maternal fetal risks. This review will cover the surgical or invasive aspect of fetal therapy with available evidence and will highlight the progress made in the management of fetal malformations in last two decades.

Tacrolimus treatment saved a rho-incompatible pregnancy

A Rho-incompatible pregnancy induces anemia in the fetus and can ultimately lead to fetal hydrops and intrauterine fetal death. A patient who had experienced recurrent implantation failures following a first successful delivery finally succeeded in achieving a second pregnancy via the use of tacrolimus. The second pregnancy was Rho-incompatible. During the course of the pregnancy, the treatment with tacrolimus was continued because the patient's T helper type 1 (Th1) cell population remained at a high level following the achievement of pregnancy. The dose was increased during pregnancy because of the elevated Th1 cell count at 28-week gestation. Tacrolimus maintains a stable state of pregnancy while simultaneously suppressing the production of anti-D antibodies. Using tacrolimus, we succeeded in resolving the infertility and inhibition of antibody production in this case of an alloimmunized pregnancy.

Efficacy of Antenatal Intravenous Immunoglobulin Treatment in Pregnancies at High Risk due to Alloimmunization to Red Blood Cells

Background

Alloimmunization to red blood cells (RBCs) may result in fetal anemia prior to 20 weeks gestation. The question as to whether early commencement of antenatal treatment with high-dose intravenous immunoglobulins (IVIG) may prevent or at least delay the development of fetal anemia in the presence of alloantibodies to RBCs is highly relevant.

Patients and Results

Here we describe a patient with high-titer anti-K and two other severely affected pregnant women with a history of recurrent pregnancy loss due to high-titer anti-D or anti-D plus anti-C. Early commencement of treatment with IVIG (1 g/kg/week) resulted in prevention of intrauterine transfusion (IUT) in the former two cases, and in a significant delay of development of fetal anemia in the remaining case (26 weeks gestation).

Conclusion

Based on our findings and of previously published cases, early initiation of treatment of severely alloimmunized women with IVIG (1 g/kg/week) could potentially improve the outcome of fetuses at risk.

Management of red blood cell alloimmunization in pregnancy

The main cause of fetal anemia is maternal red blood cell alloimmunization (AI). The search of maternal antibodies by indirect antiglobulin test allows screening for AI during pregnancy. In case of AI, fetal genotyping (for Rh-D, Rh-c, Rh-E and Kell), quantification (for anti-rhesus antibodies) and antibody titration, as well as ultrasound monitoring, are performed. This surveillance aims at screening for severe anemia before hydrops fetalis occurs. Management of severe anemia is based on intrauterine transfusion (IUT) or labor induction depending on gestational age. After intrauterine transfusion, follow-up will focus on detecting recurrence of anemia and detecting fetal brain injury. With IUT, survival of fetuses with alloimmunization is greater than 90% but 4.8% of children with at least one IUT have neurodevelopmental impairment.

Immune modulation of i.v. immunoglobulin in women with reproductive failure

Background

The mechanism of maternal immune tolerance of the semi‐allogenic fetus has been explored extensively. The immune reaction to defend from invasion by pathogenic microorganisms should be maintained during pregnancy. An imbalance between the immune tolerance to the fetus and immune activation to the pathogenic organisms is associated with poor pregnancy outcomes. This emphasizes that the immune mechanism of successful reproduction is not just immune suppression, but adequate immune modulation.

Methods

In this review, the action of i.v. immunoglobulin G (IVIg) on the immune system and its efficacy in reproductive failure (RF) was summarized. Also suggested is the indication of IVIg therapy for women with RF.

Main findings (Results)

Based on the mechanism of the immune regulation of IVIg and following confirmation of the immune modulation effects of it in various aberrant immune parameters in patients with RF, it is obvious that IVIg is effective in recurrent pregnancy losses and repeated implantation failures with immunologic disturbances.

Conclusion

The authors recommend IVIg therapy in patients with RF with aberrant cellular immunologic parameters, including a high natural killer cell proportion and its cytotoxicity or elevated T helper 1 to T helper 2 ratio, based on each clinic's cut‐off values. Further clinical studies about the safety of IVIg in the fetus and its efficacy in other immunologic abnormalities of RF are needed.

Intravenous immune globulin reduces the need for exchange transfusions in Rhesus and AB0 incompatibility

AIM

To conduct a quality control review of a single institution experience with intravenous immune globulin in the treatment of Rhesus and AB0 incompatibility.

METHODS

Intravenous immune globulin as treatment for Rhesus and AB0 incompatibility was introduced in our hospital in 1998. We performed a chart review of 176 infants with Rhesus or AB0 incompatibility treated in our hospital between 1993 and 2003, divided into a historical control group (1993-1998) and a treatment group (1999-2003). The project was approved through institutional ethics procedures.

RESULTS

The use of exchange transfusion as a therapeutic modality was significantly reduced in the cohort treated with intravenous immune globulin (OR 0.11; 95% CI 0.046-0.26, p < 0.001). We found no difference between the intravenous immune globulin group and the infants receiving only exchange transfusion as far as the duration of phototherapy. Infants with Rhesus incompatibility had a higher need for top-up transfusions than those with AB0 incompatibility.

CONCLUSION

This study supports the evidence from previous studies suggesting that intravenous immune globulin significantly reduces the need for exchange transfusion in infants with Rhesus and AB0 incompatibility.

The role of immunoglobulins in neonatal Rhesus haemolytic disease

Rhesus (Rh) isoimmunisation is the most common form of severe haemolytic disease of the newborn (HDN). The introduction of prophylaxis with anti-D Rh0 immunoglobulin (anti-D) has resulted in a marked reduction in the sensitisation of Rh-negative women and deaths attributable to Rh HDN. The sensitisation rate could be further decreased if there was strict adherence to the guidelines for administration of anti-D prophylaxis. Whether additional prophylaxis at 28 and 34 weeks of gestation would be cost effective is controversial. Intrauterine transfusions to treat fetal anaemia, postnatal exchange transfusions and phototherapy are all part of the standard management of affected individuals. Intravenous immunoglobulin given to pregnant women can reduce fetal haemolysis, and when administered to neonates with Rh isoimmunisation has been associated with a reduction in the requirement for exchange transfusion. There are, however, potential risks of immunoglobulin administration, including haemolysis due to the presence of anti-A or anti-B antibodies, allergy and the transmission of disease.

Haemolytic disease of newborn

Hemolytic disease of the newborn (HDN) occurs due to maternal IgG antibodies crossing the placenta thereby producing hemolysis mainly due to Rh, ABO and Kell groups. A systematic approach to the Rh HDN involves an obstetric history of previous isoimmunized baby, timing and regular monitoring of maternal Rh antibodies and pigment assay of amniotic fluid. Timely decision regarding in utero transfusion and early termination of pregnancy based on the maternal monitoring has radically improved the outcome of these babies. Antenatal prophylaxis with anti D has resulted in great reduction in the magnitude of Rh problem. The fetal blood sampling and in-utero intravenous transfusions has made it possible for almost 100% survival of isoimmunized pregnancies without hydrops. Alternative methods--IVIG and plasma exchange are still of limited application. ABO HDN though common is not a serious form of disease and dose not warrants invasive antenatal monitoring. Anti-Kell is found in patients having received multiple transfusions and the rapid progress of hemolysis in them may not allow such systematic follow up as in Rh HDN.

Immunoglobulin administration to fetuses with anemia due to alloimmunization to D

BACKGROUND

The purpose of this study was to examine fetal tolerance of high-dose intravenous immunoglobulin (IVIG), given directly at the time of intravascular transfusion, and its effects on fetal hemolysis and pregnancy outcome in the setting of alloimmunization to D.

STUDY DESIGN AND METHODS

Thirteen consecutive D+ fetuses requiring transfusion for maternal alloimmunization received high-dose IVIG (1.0 g/kg) and red cell transfusions. Twenty-four previous, consecutive fetuses with maternal anti-D served as controls. The schedules for subsequent transfusions were the same in the two groups.

RESULTS

High-dose IVIG was well tolerated by all fetuses. In the IVIG group, daily decreases in hematocrit were smaller than those in controls after the second administration of IVIG (mean hematocrit decrease, 0.72 percent/day vs. 1.45 percent/day; p = 0.007). No significant difference was found in the total number of fetal transfusions, the gestational age at delivery, the duration of neonatal intensive care, the number of neonates requiring postnatal transfusion therapy, and perinatal mortality.

CONCLUSION

In this small pilot study, direct administration to fetuses of IVIG with red cell transfusions was well tolerated and appeared to have a beneficial effect on fetal hemolysis.

Clinical uses of intravenous immunoglobulin in pregnancy

The obstetric literature contains numerous reports of IVIG therapy for various conditions encountered during pregnancy. The mechanisms of action of IVIG are uncertain and may vary depending on the specific disorder. Immunoglobulin G infusions appear to be well tolerated by the parturient. The occurrence of major and minor side effects is uncommon, and infectious morbidity is low. Further research will be necessary to elucidate the specific mechanisms of action of IVIG in certain disease states. Determining the exact "therapeutic agent" in IVIG for each specific disease state may allow for a more tailored approach to treatment (i.e., isolation or production of the particular antibody). Outcome assessment, long-term positive and negative effects, cost-benefit analysis, and effects on fetal and neonatal immune function require further study through randomized trials.

Immunoglobulin therapy in immunohematological disorders

Over the last few decades many biological factors have been discovered. Among these immunoglobulins are currently being used for large number of indications. Initially it was used for primary and secondary immunodeficiency states. Subsequently, intravenous immunoglobulins are being used for variety of immunohematological, autoimmune, and immunopathological disorders. In the present communication besides it basic structure, pharmacology and immunoregulation, its use in various hematological disorders is being reviewed. Currently, it is the preferred treatment for conditions such as immune mediated thrombocytopenic purpura, neutropenia, and autoimmune hemolytic anemia.

Fc receptors as targets for immunotherapy

Human membrane and soluble Fc epsilon receptors (Fc epsilon RI, Fc epsilon RII/CD23) and Fc gamma receptors (Fc gamma RI/CD64, Fc gamma RII/CD32, Fc gamma RIII/CD16) have been implicated in a number of diseases. Their functional roles such as capture and clearance of immune complexes, antibody-dependent cell cytotoxicity, or cytokine or inflammatory mediator release, make them potential targets for immuno-intervention. In the present review, we will describe how membrane and soluble human Fc epsilon R and Fc gamma R have been already used as targets/tools for immuno-interventions by using monoclonal and bispecific engineered antibodies. Some therapeutic uses of these molecules both in cancer, infectious, and auto-immune diseases are presented.

Intravenous immune globulin in the management of severe Rh D hemolytic disease

Although intrauterine fetal transfusion has improved dramatically perinatal outcome in Rh D alloimmunization, in some cases the fetus is affected before transfusion is possible. Immune globulin (IVIG) administration is being increasingly used to successfully treat a variety of immune-mediated diseases, such as pregnancies affected by platelet alloimmunization. Although only a limited number of pregnancies have been reported, favorable outcomes with IVIG treatment of severe Rh disease have been described. We present a case report, review the published experience with IVIG treatment in severe, early-onset anti-D sensitization, and propose that IVIG may have an adjunctive role in the treatment of severe Rh isoimmunization.

High-dose gammaglobulin (IVIG) followed by intrauterine transfusions (IUTs): a new alternative for the treatment of severe fetal hemolytic disease

Intrauterine fetal transfusion is currently the therapy of choice in cases of severe anti-D isoimmunisation. However, its efficacy is reduced in patients with early severe hydrops fetalis due to the technical difficulties in performing this procedure before 20 weeks' gestation. The purpose of this study was to determine whether early onset of high-dose gammaglobulin therapy followed by intrauterine transfusions (IUTs) is more effective than IUTs alone in the treatment of very severe isoimmunised fetuses. The population studied in this retrospective clinical research was assigned to one of the following two groups: 1) Gamma group: 30 patients receiving gammaglobulin therapy before 21 weeks' gestation and IUTs after 20 weeks; or 2) IUT group: 39 patients receiving IUT treatment starting at a gestational age of 20-25 weeks. Both groups were statistically similar regarding history of perinatal deaths and anti-D antibody titers. The number of hydropic fetuses at the first IUT and of fetal deaths were significantly higher in the IUT than in the Gamma group. No significant differences were observed between the groups in fetal hematocrit at first IUT and at birth. However, the percentage of severely anemic fetuses was higher in the IUT group. Fetal mortality rate was 36% less in the Gamma group. Our results suggest that high-dose gammaglobulin therapy followed by IUTs may improve fetal survival in these severe cases. Further randomised clinical trials are needed to confirm these results.

Clinical uses of intravenous immunoglobulin in pregnancy

Intravenous immunoglobulin was licensed for use in the United States in 1981. Currently, there are only a few Food and Drug Administration-labeled indications for intravenous immunoglobulin, but up to 50 "off-label" uses are reported in the literature. The obstetric literature contains numerous reports on intravenous immunoglobulin therapy during pregnancy. This article reviews the properties, pharmacokinetics, mechanisms of action, and side effects of intravenous immunoglobulin, as well as the reported uses of intravenous immunoglobulin during pregnancy.

Intravenous immunoglobulin as primary therapy or adjuvant therapy to intrauterine fetal blood transfusion: a new approach in the management of severe Rh-immunization

Maternal high dose intravenous immunoglobulin (IVIG) has shown promise in the management of severe Rh-immunization. Intravenous immunoglobulin, blocks Fe mediated antibody transport across the placenta and blocks destruction of fetal red cells and reduces maternal antibody levels. We have tried this new therapy in 6 patients with severe Rh-immunization, with high maternal antibody titres and previous hydrops and intrauterine deaths. Intravenous immunoglobulin was given from 13-18 weeks of gestation 3-4 weekly, till intrauterine transfusion (IUT) or delivery. Intensive fetal monitoring was done. No fetal hydrops or deaths occurred in any of the 6 cases. Only 2 cases needed intrauterine transfusion. IVIG delayed the onset of fetal anemia by 8-17 weeks thus deferring the need for IUT. All pregnancies continued till 32-36 weeks and all 6 babies did well in the neonatal period.

Severe Rh(D) immunization: anti-D quantitation and treatment possibilities during pregnancy and after birth

An extremely aggressive Rh(D), (C) and Kell alloimmunization during pregnancy is reported. Exceptionally high concentrations of anti-D were observed in the mother, in the fetus and in the amniotic fluid, indicating an active transport across the placenta and a passive excretion into the amniotic fluid. Treatment during pregnancy included maternal plasmapheresis and high-dose intravenous immunoglobulin. Intravascular transfusions were given to the fetus. Postpartum the newborn was given immunoglobulin, one exchange transfusion and four top-up transfusions. In the newborn the elimination rate of anti-D could be followed. Not until almost 4 months postpartum did the anti-D concentration drop below the level of detection. This coincided with an elevated reticulocyte production and appearance of the child's true blood group in parallel with ceasing need for blood transfusions. Elimination rate and absolute anti-D values can be used as a prognostic tool to predict the need of blood transfusions. Immunoglobulin treatment can also be considered as an optional form of treatment in newborns affected by alloimmunization.

Intravenous immunoglobulin infusion therapy in women with recurrent spontaneous abortions of immune etiologies

We have investigated clinical effectiveness of intravenous immunoglobulin G infusion (IVIg) on antiphospholipid antibody titers in five women with evidence of antiphospholipid antibody-associated recurrent spontaneous abortions and one with antinuclear antibody who became refractory to conventional autoimmune treatment during pregnancy and experienced pregnancy complications. Three women developed intrauterine growth retardation and three had complicated twin pregnancies with rising autoantibody titers. Antiphospholipid antibody and antinuclear antibody titers were tested pre and 2 weeks after each IVIg infusion. We report that: (i) IgG antiphospholipid antibody titers were significantly suppressed after each IVIg infusion (P < 0.05); (ii) IgM antiphospholipid antibody titers were also significantly suppressed after each IVIg infusion (P < 0.0001); (iii) decreased titers of autoantibodies paralleled increased levels of maternal IgG which lasted for at least 30 days; the autoantibodies showed a definite rise again prior to the next infusion; (iv) antinuclear antibody titers were effectively suppressed; and (v) rising autoantibody titers combined clinical manifestation of intrauterine growth retardation and women with complicated twin pregnancies. We conclude that IVIg infusion effectively suppresses IgM and IgG autoantibodies to phospholipids and antinuclear antibody in autoimmune women with a history of recurrent spontaneous abortions and refractory to conventional anticoagulation or immunosuppressive treatment.

Neonatal administration of high-dose intravenous immunoglobulin in rhesus hemolytic disease

Our aim was to assess the effectiveness of neonatal treatment of Rh hemolytic disease with high-dose intravenous immunoglobulin (HDIVIG), in reducing neonatal hemolysis. A total of 40 neonates born to isoimmunized Rh negative women were studied. The population was randomized into 2 groups: Group 1 received IVIG 800 mg/kg/day for 3 days, plus phototherapy; and Group 2 received only phototherapy. No significant difference was observed between the groups in the severity of either the antenatal and neonatal disease, mode of delivery, mean birthweight, gestational age at delivery, proportion of preterm deliveries, 1 minute Apgar Score, days of phototherapy, and presence of neonatal cholestasis. Group 1 babies showed a significantly decreased duration of hospitalization, less hemolysis, and a less marked increase in bilirubin levels on the first day of life than Group 2 newborns. Therefore, Group 1 neonates received less treatment with transfusions (exchange-transfusions and/or simple blood treatment with transfusions) than those in Group 2. Our data suggest that the frequency of transfusional therapy can be reduced by combining conventional phototherapy with HDIVIG. Further studies are needed to determine the optimum timing and dosages of neonatal HDIVIG treatment.

No beneficial effect of low-dose fetal intravenous gammaglobulin administration in combination with intravascular transfusions in severe Rh D haemolytic disease

Recent observations have shown that treatment with high-dose intravenous gammaglobulin (IVIgG) given to the mother may improve fetal outcome in cases of severe Rh D alloimmunization. Unfortunately, the costs of this new method of treatment are too high for routine use. Therefore, we decided to apply this treatment to the fetus and to investigate whether the effect of IVIgG might be attributable to blockade of the fetal mononuclear phagocyte system. We have performed a randomized study in which 20 fetuses with severe Rh D-haemolytic disease (HDN) were treated with intrauterine intravascular red cell transfusions (IUT). In 10 of these 20 cases transfusions were followed by administration to the fetus of low-dose IVIgG (85.7 +/- 11.6 mg/kg by ultrasound-estimated fetal weight because of fetal vascular volume considerations). We compared the number of IUTs, postnatal exchange transfusions, haematocrit (Ht) and haemoglobulin (Hb) values before and after transfusion (s) needed by the newborns of the two groups. No significant differences in the transfusion requirements of the fetuses and in the clinical outcome could be demonstrated. However, the 95% confidence interval for the difference in the improvement of cord blood Ht was too wide for any conclusions. The 95% confidence interval for the difference in the improvement of Hb levels suggests that any clinically relevant advantage of IVIgG on Hb is unlikely.

Human monoclonal antibodies against the rhesus D antigen from women with severe Rh immunization submitted to high-dose intravenous immunoglobulin treatment

The pre- and postpartum maternal serum anti-D concentrations of 28 women with severe Rh(D) immunization who received high-dose intravenous immunoglobulin treatment has been determined. In all cases, including 1 in which the newborn was D negative, a sharp increment in the anti-D titer was observed after delivery. The specific immunoglobulin concentration rose to levels ranging from 4.7 to 204.0 micrograms/ml and, in 20% of the patients, increments of fifty times or greater were observed. Human monoclonal antibodies (hmAb) have been produced from Epstein-Barr virus-transformed lymphoblastoid B cell lines derived from 1 of these naturally hyperimmunized patients whose serum contained an anti-D-category DVI antibody. Four anti-D-secreting cell lines (97.E3.39.214, 44.E4.R1.257, E7.R1.126.83.115 and E11V.117.63; hereafter referred to as 214, 257, 115 and 63) have been established and maintained in continuous culture for periods ranging from several months to 3 years, without loss of antibody production capacity. Antibodies 115 and 214 recognize all Du samples tested at the same level as the polyclonal positive control. Antibodies 63 and 257 show a significantly lower reaction strength with some of the Du samples. Studies with D category cells showed that the DVI category was recognized only by hmAb 214. The reactivity pattern of this antibody is that of an anti-epD4, although the reaction strength varied greatly with different DIVa cell samples. Results obtained with hmAb 257 and 115 using papain-treated D category cells suggest that booth react as anti-epD6/7.(ABSTRACT TRUNCATED AT 250 WORDS)

The role of Rh antibodies in haemolytic disease of the newborn

Recent insights into the structure-function relationship of IgG, the nature of Fc receptors and their interactions with antibodies, and the cellular mechanisms involved in the immune destruction of IgG-sensitized cells have all contributed to a fuller understanding of the role of Rh antibodies in HDN. As this understanding has increased, so different diagnostic and therapeutic approaches have been developed and evaluated in order either to predict or ameliorate disease severity. The role of Rh antibodies in HDN can be considered in three contexts: maternal anti-D, monoclonal anti-D and prophylactic anti-D. Anti-D formed after maternal alloimmunization may be transported across the placenta, resulting in destruction of sensitized red cells by mononuclear phagocytes in the fetus and infant. The use of monoclonal anti-D has given an insight into the cellular and molecular mechanisms involved in red cell destruction, and has facilitated the development and evaluation of assays which use maternal anti-D to predict the severity of HDN. Polyclonal anti-D, given prophylactically, can prevent maternal alloimmunization to D-positive fetal red cells. Future developments are likely in several areas. Prophylactic polyclonal anti-D may be replaced, wholly or partially, with monoclonal anti-D. The development and introduction of cellular assays as non-invasive tests for predicting disease severity is likely to continue as preliminary results are encouraging. Finally, new strategies for ameliorating disease severity may be assessed including the role of ivIgG and Fc gamma R-blocking antibodies.

High-dose intravenous immune globulin therapy for hyperbilirubinemia caused by Rh hemolytic disease

We conducted a multicenter controlled trial to test the hypothesis that high-dose intravenous immune globulin (HDivIG) therapy can modulate bilirubin production and reduce the frequency of exchange transfusions in newborn infants with Rh hemolytic disease. Thirty-four patients with Rh incompatibility proved by positive direct antiglobulin test (Coombs test) results were randomly assigned to receive conventional treatment including phototherapy, with or without additional HDivIG therapy at 500 mg/kg given for a 2-hour period as soon as the diagnosis was established. Exchange transfusions were performed if serum bilirubin concentrations exceeded the modified curves of Polácek by more than 2 mg/dl. Two patients were excluded because of protocol violations. The results in 32 infants were analyzed. In the HDivIG group, 2 (12.5%) of 16 children required exchange transfusions, whereas it became necessary in 11 (69%) of 16 children in the control group (p less than 0.005). Bilirubin levels in the HDivIG group were lower despite reduced frequency of exchange transfusions. No side effects of HDivIG treatment were observed. We conclude that HDivIG therapy by a yet unknown mechanism reduces serum bilirubin levels and the need for blood exchange transfusions in children with Rh hemolytic disease.

High-dose intravenous IgG for the treatment of severe rhesus alloimmunization

The value of intravenous immunoglobulin (IVIG) in the treatment of 24 severely Rh-sensitized pregnant women was studied. IVIG was infused at a daily dose of 0.4 g/kg maternal body weight for 4-5 consecutive days, and was administered again 15-21 days later until delivery, depending on the evolution of the hemolytic disease. Our population was divided into 3 groups according to the time of onset of therapy: group 1 (n = 8), before 20 weeks' gestation; group 2 (n = 7), 20-28 weeks, and group 3 (n = 9), after 28 weeks. Initial mean anti-D level was significantly higher in group 1 (25.9 +/- 12.9 IU/ml) than in the other 2 groups, whose mean values were, however, higher than 10 IU/ml. Amniotic-fluid total bilirubin levels before the onset of therapy were pathologic, and in 55% of the cases they coincided with zone 3 of Liley's chart. Hydrops fetalis at the onset of treatment accounted for the only 3 fetal deaths in groups 1 and 2. None of the fetuses developed hydrops during treatment. Six of the 9 neonates in group 3 were depressed at birth (1-min Apgar below 7). However, at 5 min only 1 newborn showed an Apgar below 7. Mean birth weight was over 2,500 g in all the cases. Neonatal hematological condition in group 2 (50% of the babies required only phototherapy) was better than in the other 2 groups (transfusional therapy). There was a significant fall in maternal anti-D titers and intrauterine hemolysis after IVIG treatment.(ABSTRACT TRUNCATED AT 250 WORDS)

Can high-dose immunoglobulin therapy be indicated in neonatal rhesus haemolysis? A successful case of haemolytic disease due to rhesus (c + E) incompatibility

A male neonate with hyperbilirubinaemia and progressing anaemia due to rhesus (c + E) incompatibility received high dose intravenous gammaglobulin (ivIgG) therapy at 13 days of age. Clinical response to therapy was confirmed by a rapid decrease in serum bilirubin level, and with the prevention of a further decline of the haemoglobin level. No side-effects were noted. High dose ivIgG therapy could be an alternative to (exchange) blood transfusion in case of some haemolytic diseases of newborn.

Management of immune haemolytic disease in the fetus

Although Rh alloimmunization has been successfully reduced in frequency and severity since the implementation of Rh immune globulin, cases still occur. The management of affected pregnancies requires the efforts of a team which includes obstetrics/fetal medicine, the blood transfusion service, haematological support, nursing assistance and neonatology. The aim of antenatal management is to predict whether or not the fetus is severely affected, to correct the fetal anaemia and to deliver the baby at the optimal time. The management has improved markedly with the introduction of high-resolution real-time ultrasound, fetal blood sampling, intravascular fetal blood transfusion and/or intraperitoneal transfusion and meticulous fetal surveillance. With appropriate and timely management in severely alloimmunized patient, the survival rate of affected fetuses in some centres is now about 90%. There is still a need for research into new methods of treatment such as high dose intravenous immunoglobulin, which might non-invasively diminish fetal red cell destruction. Due to the reduced frequency of severe disease, regionalized treatment centres are essential in order to maximize the experience and efficiency of the management teams.

A vascular effect of IgG therapy may prevent transplacental red cell leakage and spontaneous thrombocytopenic haemorrhages

It is postulated that intravenous immunoglobin therapy may improve the red cell barrier of placenta and of capillary endothelia; the former protecting against anti-Rh antibody booster reaction and the latter preventing spontaneous thrombocytopenic bleedings. The effect on permeability may also reduce the passage of anti-Rh antibodies to the foetus.

New approaches in the treatment of haemolytic disease of the fetus

The incidence of Rh haemolytic disease of the fetus and newborn complicating pregnancy has fallen since the implementation of prophylaxis with Rh immune globulin. However, occasional mismatched blood transfusions and ineffective or inadequate prophylaxis still result in a few Rh-alloimmunized patients requiring treatment during pregnancy. The development of a safe technique for obtaining pure fetal blood samples has provided the opportunity to assess correctly the severity of anaemia and to study fetal haematology and biochemical parameters, and hence to gain a better understanding of the pathophysiology of this condition. The aim of antenatal management is to predict whether or not the fetus is severely affected, to correct fetal anaemia and to deliver the baby at the optimal time. Fetal IVT is the standard treatment in severe Rh alloimmunization in many centres. However, high volume transfusion without overloading the fetal circulation, as well as increasing the interval between transfusions without jeopardizing the fetal condition, can be achieved by a combination of IVT and IPT. Thus, the total number of transfusions needed and the overall procedure-related risk for each fetus is reduced. With the recent advances in fetal medicine, haematology and neonatology, the survival rate of affected fetuses in some centres is now about 90%. Fetal death will continue to be associated with two sets of circumstances: trauma or complications due to IVT or IPT in early gestation when delivery is not feasible, and late referrals with such severe hydrops that its reversal is not possible. There is still, therefore, a need for research into new methods of treatment, such as high dose intravenous IgG, which can non-invasively diminish fetal red cell destruction.