Overview of the state of the art of Rh disease: history, current clinical management, and recent progress

An ongoing problem: Rhesus hemolytic disease of the newborn - A decade of experience in a single centre

BACKGROUND

The objectives were to evaluate the descriptive features of newborns with a diagnosis of Rhesus (Rh) hemolytic disease, to determine the morbidity and mortality rates, to evaluate the treatment methods and the factors affecting treatment requirements and clinical outcomes during a ten-year period at a tertiary center.

METHODS

Newborn infants who had a positive direct Coombs test and/or had a history of intrauterine transfusion (IUT) due to Rh hemolytic disease were included. The data regarding the prenatal, natal and postnatal periods were collected from hospital records.

RESULTS

A total of 260 neonates were included of which 51.2% were female. The mean ± standard deviation gestational age was 36.9 ± 2.7 weeks. The rate of preterm birth was 41.2%. Of 257 mothers whose obstetric medical history could be accessed, 87.2% were multigravida, whereas 76.3% were multiparous. Among mothers who had a reliable history of anti-D immunoglobulin prophylaxis (n=191), 51.3% had not received anti-D immunoglobulin prophylaxis in their previous pregnancies. The antenatal transfusion rate was 31.7% and the frequency of hydrops fetalis was 8.8%. While combined exchange transfusion (ET) and phototherapy (PT) was performed in 15.4% of the babies, the majority either needed phototherapy only (51.1%) or no treatment (33.5%). The mortality rate was 3.8 % (n = 10), and nine babies out of these 10 were those with severe hydrops fetalis.

CONCLUSION

This study showed that Rh hemolytic disease is still a major problem in developing countries. Multiple comorbidities may occur in addition to life threatening complications, including hydrops fetalis, anemia and severe hyperbilirubinemia. High rates of multiparity and low rates of anti-D immunoglobulin prophylaxis are potential barriers for the eradication of the disease. It should be remembered that Rh hemolytic disease is a preventable disease in the presence of appropriate antenatal follow-up and care facilities.

Neonatal nonimmune hemolytic anemia

PURPOSE OF REVIEW

As in adults and older children, anemia in newborn infants can be the result of erythropoietic failure, hemorrhage, or hemolysis. When hemolysis is the prime consideration, it can be challenging for physicians caring for neonates to choose from the wide variety of available diagnostic tests. This review describes the authors' opinions regarding rational, consistent, and cost-effective means of making an exact diagnosis of a neonatal hemolytic condition.

RECENT FINDINGS

Two recent advances in the diagnosis of neonatal nonimmune hemolytic disorders are highlighted in this review: introduction of flow cytometry-based Eosin-5-maleimide (EMA) uptake as a screening test to identify RBC membrane defects and next-generation sequencing (NGS)-based panels to uncover exact mutations causing hemolysis.

SUMMARY

The availability of newer tools such as EMA and NGS to diagnose specific hemolytic conditions, which might otherwise remain unknown, enables neonatal practitioners not only to identify the exact cause of hemolysis but also to discover novel mutations that can be implicated in the cause of neonatal hemolytic processes.

Long-term cardiovascular outcome following fetal anaemia and intrauterine transfusion: a cohort study

OBJECTIVE

To compare long-term cardiovascular outcomes in survivors of fetal anaemia and intrauterine transfusion with those of non-anaemic siblings.

DESIGN

Retrospective cohort study.

SETTING

Auckland, New Zealand.

PARTICIPANTS

Adults who received intrauterine transfusion for anaemia due to rhesus disease (exposed) and their unexposed sibling(s).

EXPOSURE

Fetal anaemia requiring intrauterine transfusion.

MAIN OUTCOME MEASURES

Anthropometry, blood pressure, lipids, heart rate variability and cardiac MRI, including myocardial perfusion.

RESULTS

Exposed participants (n=95) were younger than unexposed (n=92, mean±SD 33.7±9.3 vs 40.1±10.9 years) and born at earlier gestation (34.3±1.7 vs 39.5±2.1 weeks). Exposed participants had smaller left ventricular volumes (end-diastolic volume/body surface area, difference between adjusted means -6.1, 95% CI -9.7 to -2.4 mL/m²), increased relative left ventricular wall thickness (difference between adjusted means 0.007, 95% CI 0.001 to 0.012 mm.m²/mL) and decreased myocardial perfusion at rest (ratio of geometric means 0.86, 95% CI 0.80 to 0.94). Exposed participants also had increased low frequency-to-high frequency ratio on assessment of heart rate variability (ratio of geometric means 1.53, 95% CI 1.04 to 2.25) and reduced high-density lipoprotein concentration (difference between adjusted means -0.12, 95% CI -0.24 to 0.00 mmol/L).

CONCLUSIONS

This study provides the first evidence in humans that cardiovascular development is altered following exposure to fetal anaemia and intrauterine transfusion, with persistence of these changes into adulthood potentially indicating increased risk of cardiovascular disease. These findings are relevant to the long-term health of intrauterine transfusion recipients, and may potentially also have implications for adults born preterm who were exposed to anaemia at a similar postconceptual age.

Routine antenatal anti-D prophylaxis in women who are Rh(D) negative: meta-analyses adjusted for differences in study design and quality

BACKGROUND

To estimate the effectiveness of routine antenatal anti-D prophylaxis for preventing sensitisation in pregnant Rhesus negative women, and to explore whether this depends on the treatment regimen adopted.

METHODS

Ten studies identified in a previous systematic literature search were included. Potential sources of bias were systematically identified using bias checklists, and their impact and uncertainty were quantified using expert opinion. Study results were adjusted for biases and combined, first in a random-effects meta-analysis and then in a random-effects meta-regression analysis.

RESULTS

In a conventional meta-analysis, the pooled odds ratio for sensitisation was estimated as 0.25 (95% CI 0.18, 0.36), comparing routine antenatal anti-D prophylaxis to control, with some heterogeneity (I²  =  19%). However, this naïve analysis ignores substantial differences in study quality and design. After adjusting for these, the pooled odds ratio for sensitisation was estimated as 0.31 (95% CI 0.17, 0.56), with no evidence of heterogeneity (I²  =  0%). A meta-regression analysis was performed, which used the data available from the ten anti-D prophylaxis studies to inform us about the relative effectiveness of three licensed treatments. This gave an 83% probability that a dose of 1250 IU at 28 and 34 weeks is most effective and a 76% probability that a single dose of 1500 IU at 28-30 weeks is least effective.

CONCLUSION

There is strong evidence for the effectiveness of routine antenatal anti-D prophylaxis for prevention of sensitisation, in support of the policy of offering routine prophylaxis to all non-sensitised pregnant Rhesus negative women. All three licensed dose regimens are expected to be effective.

Long-term neurodevelopmental outcome after intrauterine transfusion for hemolytic disease of the fetus/newborn: the LOTUS study

OBJECTIVE

To determine the incidence and risk factors for neurodevelopmental impairment (NDI) in children with hemolytic disease of the fetus/newborn treated with intrauterine transfusion (IUT).

STUDY DESIGN

Neurodevelopmental outcome in children at least 2 years of age was assessed using standardized tests, including the Bayley Scales of Infant Development, the Wechsler Preschool and Primary Scale of Intelligence, and the Wechsler Intelligence Scale for Children, according to the children's age. Primary outcome was the incidence of neurodevelopmental impairment defined as at least one of the following: cerebral palsy, severe developmental delay, bilateral deafness, and/or blindness.

RESULTS

A total of 291 children were evaluated at a median age of 8.2 years (range, 2-17 years). Cerebral palsy was detected in 6 (2.1%) children, severe developmental delay in 9 (3.1%) children, and bilateral deafness in 3 (1.0%) children. The overall incidence of neurodevelopmental impairment was 4.8% (14/291). In a multivariate regression analysis including only preoperative risk factors, severe hydrops was independently associated with neurodevelopmental impairment (odds ratio, 11.2; 95% confidence interval, 1.7-92.7).

CONCLUSION

Incidence of neurodevelopmental impairment in children treated with intrauterine transfusion for fetal alloimmune anemia is low (4.8%). Prevention of fetal hydrops, the strongest preoperative predictor for impaired neurodevelopment, by timely detection, referral and treatment may improve long-term outcome.

Blood exchange transfusion for infants with severe neonatal hyperbilirubinemia

Blood exchange transfusion has become a rare event in most developed countries. As a result, many pediatricians may not have performed or even seen one. However, it remains a frequent emergency rescue procedure for severe neonatal hyperbilirubinemia in many underdeveloped regions of the world. Conventionally, exchange transfusion has been performed via a central umbilical venous catheter by pull-push cycle method and recently peripheral artery/peripheral vein has emerged as an alternative, isovolumetric route. Continuous arterio-venous exchange is possibly more effective though its automation has not been successful. Concerns for procedural and operator related adverse events have been raised in the context of declining indications. A required continued expertise for this life-saving intervention, in the face of rare but critical hyperbilirubinemia and/or unrecognized hemolytic diseases, deserves adaptation of newer technologies to make neonatal exchange transfusion a safer and more effective procedure. Technological innovations and simulation technologies are urgently needed.

Rhesus haemolytic disease of the newborn: Postnatal management, associated morbidity and long-term outcome

Rhesus haemolytic disease of the newborn can lead to complications such as hyperbilirubinaemia, kernicterus and anaemia. Postnatal management consists mainly of intensive phototherapy, exchange transfusion and blood transfusion. During the last decades, significant progress in prenatal care strategies for patients with Rhesus haemolytic disease has occurred. New prenatal management options have led to a remarkable reduction in perinatal mortality. As a result of the increase in perinatal survival, attention is now shifting towards short-term and long-term morbidity. This review focuses on the management of neonatal and paediatric complications associated with Rhesus haemolytic disease, discusses postnatal treatment options and summarizes the results of studies on short-term and long-term outcome.

Blood product replacement in the perinatal period

OBJECTIVE

In this article, we will describe some of the special compatibility testing procedures and blood component preparation and modification techniques used in intrauterine and neonatal transfusion medicine. We also will review the transfusion therapy used in hemolytic disease of the fetus and newborn (HDFN) and fetal and neonatal alloimmune thrombocytopenia (FNAIT).

FINDING

Transfusion therapy in the fetus and neonate requires blood typing and compatibility testing techniques not routinely used for adults. These include: cord blood testing, special attention to the volume and speed of infusion, cytomegalovirus risk reduction, and routine irradiation of cellular blood components. The treatment of HDFN and FNAIT involves phenotyping and/or genotyping of fetal and paternal red blood cells and platelets. In FNAIT, platelet products are chosen based on the absence of platelet-specific antigens.

CONCLUSION

Fetal and neonatal transfusion medicine require special attention to the unique anatomic and physiologic features of early human development.

Haemolytic disease of the newborn

The changing management of haemolytic disease of the newborn is reviewed

Adverse events associated with neonatal exchange transfusion in the 1990s

OBJECTIVE

To determine the rates of adverse events associated with neonatal exchange transfusions performed for hyperbilirubinemia.

STUDY DESIGN

Retrospective chart review of 55 neonates who underwent 66 exchange transfusions at two perinatal centers in Cleveland between 1992 and 2002. Demographic data, causes of jaundice, details of exchange method, and adverse events occurring within one week of exchange were recorded. At the time of exchange, 62% of infants had other neonatal morbidities. Outcomes were stratified according to gestational ages < or =32 weeks, 33 to 36 weeks, and > or =37 weeks.

RESULTS

Overall, 74% of exchanges were associated with an adverse event. The most common events were thrombocytopenia (44%), hypocalcemia (29%), and metabolic acidosis (24%), of which 69%, 74%, and 44%, respectively, required treatment. There were two serious adverse events, both in infants with other serious neonatal morbidities: seizures in one infant and the death of a critically ill preterm infant (body weight 731 g, gestational age 25 weeks). There were no cases of sepsis, necrotizing enterocolitis, or cardiac arrest. Adverse events were more frequent in exchanges done on preterm infants: < or =32 weeks (87%), 33 to 36 weeks (78%), and > or =37 weeks (67%), and in infants with other neonatal morbidity (79% vs 57%; P=.08). Controlling for neonatal morbidity, we found the odds of an adverse event were significantly higher when both umbilical venous and arterial catheters were used compared with other methods of exchange (88% vs 58%; OR, 5.17; 95% CI, 1.1, 34.2; P=.03).

CONCLUSIONS

The majority of adverse events associated with exchange transfusion are laboratory abnormalities and are asymptomatic and treatable.