Unusually severe ABO hemolytic disease of newborn

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.

Hemolysis due to Alpha-Hemolytic Enterococcus Urinary Infection: A Rare Cause of Early and Severe Unconjugated Hyperbilirubinemia in a Neonate

The reason for reporting this case is to remind that some microorganisms may cause hemolysis leading to early and severe hyperbilirubinemia by secreting hemolysin in cases; where bilirubin levels cannot be successfully decreased despite effective phototherapy, intravenous immunoglobulin, and even exchange transfusion, or in cases of increased rebound bilirubin (although urinary tract infection is associated with increased conjugated bilirubin fraction and prolonged jaundice). The most common causes of hemolysis are ABO/Rh incompatibility and enzyme deficiencies such as glucose-6-phosphate dehydrogenase (G6PDH), pyruvate kinase (PK), and galactose-1-phosphate uridyltransferase (GALT). Our patient was a male infant, weighing 3,160 g, at 38 + 4 gestational week; he was referred to our unit with total bilirubin level of 14.7 mg/dL recorded at the postnatal 20th hour and was initiated treatment with intensive phototherapy and prepared for exchange transfusion. The G6PD, PK, and GALT enzyme levels studied at the postnatal 96th hour and reducing substances in urine were detected to be normal/negative, whereas complete urinalysis revealed pyuria (7 leukocytes per each high power field). α-hemolysis-producing 105 colony-forming unit/mL Enterobacter cloacae grew on blood agar in the urine culture. As reported in our case, hemolysin-secreting α and β-hemolytic bacteria can lead to severe and early hemolysis and unconjugated hyperbilirubinemia, as in blood type incompatibility and enzyme deficiencies.

Next Generation Sequencing-Based Fetal ABO Blood Group Prediction by Analysis of Cell-Free DNA from Maternal Plasma

Introduction

ABO blood group incompatibility between a pregnant woman and her fetus as a cause of morbidity or mortality of the fetus or newborn remains an important, albeit rare, risk. When a pregnant woman has a high level of anti-A or anti-B IgG antibodies, the child may be at risk for hemolytic disease of the fetus and newborn (HDFN). Performing a direct prenatal determination of the fetal ABO blood group can provide valuable clinical information.

Objective

Here, we report a next generation sequencing (NGS)-based assay for predicting the prenatal ABO blood group.

Materials and Methods

A total of 26 plasma samples from 26 pregnant women were tested from gestational weeks 12 to 35. Of these samples, 20 were clinical samples and 6 were test samples. Extracted cell-free DNA was PCR-amplified using 2 primer sets followed by NGS. NGS data were analyzed by 2 different methods, FASTQ analysis and a grep search, to ensure robust results. The fetal ABO prediction was compared with the known serological infant ABO type, which was available for 19 samples.

Results

There was concordance for 19 of 19 predictable samples where the phenotype information was available and when the analysis was done by the 2 methods. For immunized pregnant women (n = 20), the risk of HDFN was predicted for 12 fetuses, and no risk was predicted for 7 fetuses; one result of the clinical samples was indeterminable. Cloning and sequencing revealed a novel variant harboring the same single nucleotide variations as ABO*O.01.24 with an additional c.220C>T substitution. An additional indeterminable result was found among the 6 test samples and was caused by maternal heterozygosity. The 2 indeterminable samples demonstrated limitations to the assay due to hybrid ABO genes or maternal heterozygosity.

Conclusions

We pioneered an NGS-based fetal ABO prediction assay based on a cell-free DNA analysis from maternal plasma and demonstrated its application in a small number of samples. Based on the calculations of variant frequencies and ABO*O.01/ABO*O.02 heterozygote frequency, we estimate that we can assign a reliable fetal ABO type in approximately 95% of the forthcoming clinical samples of type O pregnant women. Despite the vast genetic variations underlying the ABO blood groups, many variants are rare, and prenatal ABO prediction is possible and adds valuable early information for the prevention of ABO HDFN.

Severe ABO Hemolytic Disease of the Newborn Requiring Exchange Transfusion

ABO incompatibility (ABOi), the most common cause of hemolytic disease of the newborn (HDN), is nearly always mild and treatable with phototherapy. Reports of ABOi HDN requiring neonatal exchange transfusion are extremely rare since the inception of modern guidelines. Here, a case of ABOi HDN clearly met criteria for exchange transfusion. An O-positive African American mother delivered a B-positive neonate that quickly developed hyperbilirubinemia. The neonatal DAT was positive from anti-B and anti-A,B, and maternal IgG titer was 1024. Double volume exchange transfusion resulted in a favorable outcome. Given early discharge of newborns, further understanding of factors predicting severe disease is needed.

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.

Morbidity of ABO haemolytic disease in the newborn

BACKGROUND

Better understanding of the clinical characteristics of ABO haemolytic disease in neonates helps optimise care.

OBJECTIVE

To assess the morbidity associated with maternal-neonatal ABO incompatibility.

METHODS

Neonates with blood groups A or B born to mothers with blood group O with simultaneous rhesus blood factor compatibility were studied prospectively. Maternal and neonatal details, direct Coomb's test (DCT) on the cord blood, onset and progression of jaundice, and requirement and duration of phototherapy were studied. Neonates requiring phototherapy were considered to have significant hyperbilirubinaemia, and peripheral smear, reticulocyte count and haematocrit values were obtained. ABO haemolytic disease of the newborn (ABO HDN) is defined as a newborn with a positive DCT and/or laboratory evidence of haemolysis such as reticulocytosis and spherocytes on blood smear.

RESULTS

Of 878 deliveries, 151 (17.3%) neonates were ABO incompatible with their mothers. The proportions who were O-A and O-B incompatible were 50.4% and 49.6%, respectively. Forty-six (30.4%) had significant hyperbilirubinaemia (119.7-256.5 mmol/L) and required phototherapy, 26 (34.2%) of them in the O-A group and 20 (26.6%) in the O-B group. None required exchange transfusion. Jaundice was detected within the first 24 hours in 47.8%. Of 46 newborns who required phototherapy, 25 (54.3%) had laboratory evidence of haemolysis. DCT was positive in 1.9% of ABO-incompatible newborns. There was no significant difference in the incidence and severity of haemolysis between the O-A and O-B-incompatible neonates. Neonates with haemolysis required phototherapy significantly earlier and for longer than neonates without haemolysis (P<0.001).

CONCLUSIONS

ABO incompatibility was observed in 17.3% of pregnancies with almost equal O-A and O-B frequency. About a third of infants had significant hyperbilirubinaemia. There was no difference in severity between those with O-A and O-B HDN.

Hemolytic disease of the fetus and newborn: Current trends and perspectives

The spectrum of hemolytic disease of the newborn has changed over the last few decades. With the implementation of Rhesus D immunoprophylaxis, hemolytic disease due to ABO incompatibility and other alloantibodies has now emerged as major causes of this condition. Though in developing countries, anti D is still a common antibody in pregnant women, many Asian countries have identified alloantibodies other than anti D as a cause of moderate-severe hemolytic disease. The most concerned fact is that, some of these have been described in Rh D positive women. It appears that universal antenatal screening in all pregnant women needs to be initiated, since Rh D positive women are just as likely as D negative women to form alloantibodies. Many developed nations have national screening programs for pregnant women. This is necessary to ensure timely availability of antigen negative blood and reduce effects on the newborn. Although universal screening seems justified, the cost and infrastructure required would be immense. Developing countries and under resourced nations need to consider universal antenatal screening and frame guidelines accordingly.