Detection of high risk pregnancies with relation to ABO haemolytic disease of newborn

A study on diagnostic performance of different immunohematological diagnostic tests in assessing the prevalence of ABO Hemolytic Disease of Newborn in the antenatal O group mothers and their neonatal outcome in a tertiary care hospital in Northern India

BACKGROUND

Hemolytic disease of the newborn (HDN) results in the decreased lifespan of the red cells. HDN related to ABO incompatibility is mostly unnoticed because routine screening is not being done. This study was done to assess the prevalence of ABO-HDN and to compare different immunohematological tests. Methods-In this study 213 O group mothers and the 122 ABO-incompatible newborns born to them were included. Quantifying the maternal IgG anti-A/anti-B antibody titer was done by Conventional Tube Technique (CTT) using Dithiothreitol (DTT) pretreated maternal serum. Hemolysin test was performed on the mothers having titer > 256. These cases were followed up and, after delivery, were monitored for ABO HDN, along with direct antiglobulin testing and elution studies. The prevalence of ABO-HDN was calculated, and the different diagnostic parameters of the tests were calculated. Results- The prevalence of ABO-HDN in our population was estimated to be 1.7%, 6.1% & 10.6% in our population, O group mothers, and O group mothers with ABOincompatible newborns, respectively. Maternal titer≥ 512 strongly correlated with ABOHDN. DAT positivity is a good predictor of ABO-HDN, especially using sensitive techniques. Maternal IgG titers have the highest sensitivity & Negative Predictive Value, while DAT has the highest specificity & Positive Predictive Value. Conclusion - Maternal ABO antibody titration may be advocated in the centers to identify high-risk groups. It can advocate institutional delivery and dedicated follow-up of newborns with ABO-HDN. Blood grouping & DAT may be performed in all newborns born to O blood group to identify high-risk cases.

Hemolytic Disease of Newborn due to ABO Incompatibility between B Blood Group Mother and A Blood Group Neonate

ABO incompatibility between O blood group mother and non–O blood group neonate is common. It rarely causes anemia and hyperbilirubinemia in neonate, requiring invasive management. Direct antiglobulin test may be positive in these cases with immunoglobulin (Ig)-G antibody specificity. There are few cases of hemolytic disease of newborn due to ABO incompatibility between mother and newborn with non ̶ O blood group mother. After obtaining consent from the patient, we reported a case of incompatibility in a B blood group mother and A blood group neonate, and it was managed with phototherapy.

Statistical model for prediction of ABO hemolytic disease of the fetus and newborn in India

ABO incompatibility is the most common cause of immune hemolytic disease of the fetus and newborn (HDFN). The American Academy of Pediatrics lists blood group incompatibility as one of the major risk factors for severe hyperbilirubinemia in newborns. We have estimated the risk of ABO HDFN to determine the need for its routine screening. Blood group data from all blood donors who donated in the last 10 years were collected and analyzed. The population prevalence of ABO blood group genes using the phenotype data of blood donors was estimated. This information was further used to calculate an incidence of ABO HDFN requiring intervention in the population. ABO blood group typing was analyzed in 425,743 blood donors. The ABO phenotypes of A, B, O, and AB were 22.48, 36.73, 31.59, and 9.2 percent, respectively. The gene frequencies were 0.1733, 0.2647, and 0.5620 for A, B, and O, respectively. It was estimated that 13.84 percent of group O women would give birth to a non-group O baby and that approximately 2.77 percent of deliveries would likely have ABO HDFN in the study population. In India, the estimated risk of ABO HDFN is 2.9 percent, with a daily 2196 babies at risk of ABO HDFN requiring intervention. This analysis estimates the overall burden of ABO HDFN in the population, which could aid in the decision-making of policymakers, physicians, and community health practitioners to improve neonatal care.

ABO incompatibility is the most common cause of immune hemolytic disease of the fetus and newborn (HDFN). The American Academy of Pediatrics lists blood group incompatibility as one of the major risk factors for severe hyperbilirubinemia in newborns. We have estimated the risk of ABO HDFN to determine the need for its routine screening. Blood group data from all blood donors who donated in the last 10 years were collected and analyzed. The population prevalence of ABO blood group genes using the phenotype data of blood donors was estimated. This information was further used to calculate an incidence of ABO HDFN requiring intervention in the population. ABO blood group typing was analyzed in 425,743 blood donors. The ABO phenotypes of A, B, O, and AB were 22.48, 36.73, 31.59, and 9.2 percent, respectively. The gene frequencies were 0.1733, 0.2647, and 0.5620 for A, B, and O, respectively. It was estimated that 13.84 percent of group O women would give birth to a non–group O baby and that approximately 2.77 percent of deliveries would likely have ABO HDFN in the study population. In India, the estimated risk of ABO HDFN is 2.9 percent, with a daily 2196 babies at risk of ABO HDFN requiring intervention. This analysis estimates the overall burden of ABO HDFN in the population, which could aid in the decision-making of policymakers, physicians, and community health practitioners to improve neonatal care.

Clinical Implication of Immunohaematological Tests in ABO haemolytic disease of newborn: Revisiting an old disease

OBJECTIVE

We aimed to assess the frequency distribution of of ABO haemolytic disease of newborn (ABO-HDN) and to know the predictive value of immunohaematological tests in identifying at risk neonates.

BACKGROUND

ABO incompatibility, although a common cause of haemolytic disease of newborn, has several unaddressed issues related to it.

MATERIAL AND METHODS

A prospective study over 20 months was carried out in a tertiary care centre in South India. Blood grouping, Direct Antiglobulin test (DAT) and elution studies were performed on neonatal samples, whereas blood grouping, antibody screening and antibody titration were performed on maternal samples. In suspected cases, ABO-HDN was diagnosed after excluding other possible causes for haemolysis. The laboratory results were correlated with the clinical details to assess the predictive value of the tests.

RESULTS

Of the total 2856 pregnancies, 34% had ABO incompatibility. On testing with columnagglutination test (CAT), the overall DAT positivity and that among ABO-incompatible cases were 3.8% and 11.2%, respectively,) whereas by conventinal tube technique (CTT) it was 0.6% and 2.4% respectively. CAT was found to have higher sensitivity, and the predictive value was higher for CTT. Maternal IgG titre showed a positive linear relationship with the DAT strength and the rise in indirect bilirubin levels. The positive predictive value of combination of tests such as DAT, elution and titation was 94.12%, which was much higher than that of the individual tests.

CONCLUSION

DAT positivity is a predictor of early rise in serum bilirubin level, and a combination of tests has a better predictive value than individual tests towards development of clinically significant hyperbilirubinemia in ABO-HDN.

Severe ABO hemolytic disease of fetus and newborn requiring blood exchange transfusion

ABO incompatibility and other alloantibodies have emerged as a significant cause of hemolytic disease of fetus and newborn (HDFN), leading to neonatal morbidity and mortality. We report three cases of severe ABO-HDFN where blood exchange transfusions (ETs) were required in neonates with hyperbilirubinemia. Blood grouping (ABO/RhD) was performed using conventional tube technique. The antibody screen was done using commercial three-cell panel (Bio-Rad ID-Diacell-I-II-III, Switzerland) by gel technique. Direct antiglobulin test (DAT) on neonatal sample and compatibility testing were also done by gel technique. Elution on DAT-positive sample was performed using “heat elution” method. All the three neonates were A RhD positive and were born to O RhD-positive mothers who were negative for antibody screen. Their DAT was positive (2+) and the elution of neonatal red cells yielded a positive reaction with A cells which was suggestive of anti-A antibody. The maternal anti-A (immunoglobulin G) antibody titers were high: 512 and 1024 (in two cases). The total serum bilirubin (mg/dl) of the three neonates was 22, 27, and 25 which came down significantly after they received ETs. Severe ABO-HDFN may occur in neonates born to mother with high titer ABO antibodies which can be effectively managed with ET.

Intravenous Immunoglobulin G Treatment in ABO Hemolytic Disease of the Newborn, is it Myth or Real?

Intravenous Immunoglobulin G (IVIG) therapy has been used as a component of the treatment of hemolytic disease of the newborn. There is still no consensus on its use in ABO hemolytic disease of the newborn routinely. The aim of this study is to determine whether administration of IVIG to newborns with ABO incompatibility is necessary. One hundred and seventeen patients with ABO hemolytic disease and positive Coombs test were enrolled into the study. The subjects were healthy except jaundice. Infants were divided into two groups: Group I (n = 71) received one dose of IVIG (1 g/kg) and LED phototherapy whereas Group II (n = 46) received only LED phototherapy. One patient received erythrocyte transfusion in Group I, no exchange transfusion was performed in both groups. Mean duration of phototherapy was 3.1 ± 1.3 days in Group I and 2.27 ± 0.7 days in Group II (p < 0.05). Mean duration of hospital stay was 5.34 ± 2.2 days in Group I and 3.53 ± 1.3 days in Group II (p < 0.05). Mean duration of phototherapy was 4.0 ± 1.5 days and 2.73 ± 1.1 days in double and single doses of IVIG respectively, and this was statistically significant (p < 0.05). IVIG therapy didn't decrease neither phototherapy nor hospitalization duration in infants with ABO hemolytic disease. Meticulus follow-up of infants with ABO hemolytic disease and LED phototherapy decreases morbidity. IVIG failed to show preventing hemolysis in ABO hemolytic disease.

Single versus multiple dose intravenous immunoglobulin in combination with LED phototherapy in the treatment of ABO hemolytic disease in neonates

Intravenous immunoglobulin (IVIG) has been found to decrease hemolysis in neonatal jaundice due to blood group incompatibility, but a consensus on its usage has not been reached. We conducted a study to compare single versus multiple dose of IVIG in combination with light emitting diode (LED) phototherapy in patients with neonatal jaundice secondary to ABO blood incompatibility, and compared the efficacy of these treatments with that in a group of patients who received LED phototherapy solely. Thirty-nine term neonates with ABO blood group incompatibility were enrolled in the study. Group I received one dose of IVIG (1 g/kg) and LED phototherapy, and group II two doses of IVIG (1 g/kg) and LED phototherapy, whereas group III received LED phototherapy only. In group I, exchange transfusion was performed in one patient (6%) and in group II in one patient (10%). In the control group, none of the patients required exchange transfusion. Duration of LED phototherapy was 4.3 ± 0.7 days in group I + II (IVIG group), 3.9 ± 0.6 days in group III (P = 0.06). Lowest hematocrit level in group I + II was 35.0 ± 7.8 and group III was 38.9 ± 4.2, this was statistically significant (P = 0.034). IVIG therapy, single or multiple, did not affect exchange transfusion, need of erythrocyte transfusion and hospitalization time when used in combination with LED phototherapy in the treatment of ABO hemolytic jaundice in neonates.

Use of maternal plasma for non-invasive prenatal diagnosis of fetal ABO genotypes

BACKGROUND

Measurement of free fetal DNA in maternal plasma opened a door for non-invasive prenatal diagnosis. Prenatal diagnosis of fetal ABO genotypes can provide a basis for the prevention and therapy of maternal-fetal incompatibility. We identified fetal ABO genotypes using fetal DNA in plasma from pregnant women with blood group O. The aim of the study was to investigate the accuracy and feasibility of this method.

METHODS

A total of 105 blood group O women in middle or late pregnancy were enrolled. Fetal DNA in maternal plasma and genomic DNA in umbilical vein blood from newborns were extracted using a QIAamp DNA Blood Kit. DNA was amplified to identify ABO genotypes by PCR with sequence-specific primers (PCR-SSP). The genotype results were evaluated using serologic tests for ABO phenotyping.

RESULTS

Using DNA from umbilical vein blood, ABO genotypes of 105 newborns were successfully identified by PCR-SSP. Using fetal DNA from maternal plasma, 88.6% (93/105) fetal ABO genotypes was correct; 12 false results were from 66 pregnant women with fetuses of type non-O. The accuracy in middle pregnancy was lower than that in late pregnancy, although the difference was not significant (0.05<p<0.10).

CONCLUSIONS

It is feasible to use measurement of fetal DNA in plasma from pregnant women with blood group O for prenatal diagnosis of fetal ABO genotypes. The method is useful for the diagnosis and therapy of ABO maternal-fetal incompatibility and hemolytic disease of the newborn.

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.