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

The Severity of Direct Antiglobulin Test Negative ABO Hemolytic Disease of Newborn: A Retrospective Analysis at a Tertiary Children's Hospital

This study aimed to evaluate the severity of ABO hemolytic disease of newborn (ABO-HDN) with negative direct antiglobulin test (DAT), which was identified by elution test. We retrospectively reviewed the clinical records of all neonates admitted with the diagnosis of neonatal hyperbilirubinemia requiring phototherapy or exchange transfusion. Neonates were divided into four groups according to their immunohematology test results. Then their essential laboratory results, magnetic resonance image (MRI), brainstem auditory evoked potential (BAEP) findings, and rate of exchange transfusion were compared between different groups. We found that neonates in ABO-HDN with negative DAT group developed jaundice faster and anaemia more severely than those in the non-HDN group. Although they might get less severe anaemia than neonates in ABO-HDN with positive DAT group and the Rh-HDN group, neonates in ABO HDN with negative DAT group might develop jaundice as quickly as the latter two groups. As to MRI and BAEP findings, there were no significant differences among the four groups. The rate of exchange transfusion in ABO-HDN with negative DAT group was higher than that in the non-HDN group but lower than that in ABO-HDN with positive DAT group, though without statistical significance. It suggested that in the presence of clinical suspicion of ABO-HDN with negative DAT result, the elution test should be added to rule out or confirm the diagnosis to help prevent the morbidity from hyperbilirubinemia.

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.

Neonatal hemolytic disease: How should we use indirect and direct antiglobulin tests?

BACKGROUND

In newborns with hemolysis, the direct antiglobulin test (DAT) and indirect antiglobulin test (IAT) play a key role in demonstrating the presence of an immune cause. We aimed to emphasize the importance of IAT in mothers of DAT-positive babies.

METHODS

DAT was performed with forward blood grouping on cord blood in term babies who were born between September 2020 and September 2022. IAT was performed in the mothers of the babies who were found to have a positive DAT and antibody identification was performed in the mothers who were found to have a positive IAT. Specific antibodies detected and identified were associated with the clinical course.

RESULTS

The study included 2769 babies and their mothers. The prevalence of DAT positivity was found to be 3.3% (87 of 2661). In DAT-positive babies, the rate of ABO incompatibility was 45.9%, the rate of RhD incompatibility was 5.7% and the rate of RhD and ABO incompatibility in association was 10.3%. The rate of subgroup incompatibility and other red blood cell antibodies was 18.3%. Phototherapy was applied because of indirect hyperbilirubinemia in 16.6% of the DAT-negative babies and in 51.5% of the DAT-positive babies. The need for phototherapy was significantly higher in DAT-positive infants (p < 0.01). Severe hemolytic disease of the newborn, bilirubin level, duration of phototherapy and use of intravenous immunoglobulin were found to be significantly higher in the babies whose mothers were IAT positive compared with the babies whose mothers were IAT negative (p < 0.01).

CONCLUSIONS

IAT should be performed on all pregnant women. When screening with IAT is not performed during pregnancy, performing DAT in the baby plays a key role. We showed that the clinical course was more severe when mothers of DAT-positive babies were IAT positive.

Clinical value of combination detection of direct antiglobulin test and serum albumin globulin ratio in severe hyperbilirubinemia caused by ABO hemolytic disease of the newborn

Background To explore of a combination of antiglobulin test(DAT) and albumin globulin ratio(AGR) could predict the severity of ABO hemolytic disease of the newborn(ABO-HDN).Methods The measurement of DAT, AGR and combination detection of DAT and AGR was done to predict severe ABO-HDN hyperbilirubinemia in 270 full-term infants based on whether the infants received transfusions of blood components. The infants were divided into three groups according to the results of DAT and ARG and compared the differences of phototherapy day and hospitalization day of the three groups.Results Of the 270 cases enrolled in this study, 69 infants were DAT positive. Peak total bilirubin, AGR, and positive DAT were independently associated with the need for blood components transfusion. ROC curve analysis for blood components transfusion showed that DAT cutoff value >± with a sensitivity of 39.4% and a specificity of 83.9%, AGR cutoff value <2.05 with a sensitivity of 54.1% and a specificity of 85.7%, and combination detection of DAT and ARG with a sensitivity of 62.1% and a specificity of 91.2%. The AUCs for DAT, AGR, and combination detection of DAT and AGR were .621, .740, and .750 respectively. The phototherapy day and hospitalization day were significantly longer in group of AGR <2.05 and DAT >± than that of a group of AGR <2.05 and group of DAT >±.Conclusions DAT and ARG could be early predictors for the severity ABO-HDN hyperbilirubinemia and combination detection of DAT and AGR could further increase its predictive value.

Coagulation profile of neonates with hyperbilirubinaemia in full-term newborns

OBJECTIVE

To determine the relationship between coagulation system markers and hyperbilirubinaemia in full-term neonates.

METHODS

This retrospective case-control study enrolled full-term neonates with hyperbilirubinaemia and healthy control full-term neonates. Prothrombin time (PT), thrombin time (TT), fibrinogen (Fbg), activated partial thromboplastin time (APTT) and international normalized ratio (INR) were recorded. The correlation between INR and total bilirubin and between INR and indirect bilirubin was analysed by linear regression analysis. Receiver operating characteristic curve analysis was used to assess the efficacy of INR to identify neonates with hyperbilirubinaemia.

RESULTS

This study enrolled 40 full-term neonates with hyperbilirubinaemia and 30 healthy controls. PT, INR and APTT were significantly higher in the neonates with hyperbilirubinaemia compared with the healthy controls. There was a significant positive correlation between INR and the level of total bilirubin in neonates with hyperbilirubinaemia (R = 0.3327). There was also a significant positive correlation between INR and the level of indirect bilirubin in neonates with hyperbilirubinaemia (R = 0.3406). INR in neonates with hyperbilirubinaemia significantly achieved an area under the curve of 0.800 (95% confidence interval, 0.6288, 0.9712; cut-off value, 1.060; specificity, 71.43%; sensitivity, 80.00%).

CONCLUSION

These findings suggest that INR is a novel biomarker for the diagnosis of neonatal hyperbilirubinaemia in full-term neonates.

Immunohematological testing and transfusion management of the prenatal patient

The primary indication for immunohematological testing in the prenatal patient is to detect and identify maternal red cell antibodies. If there are antibodies that are expected to hemolyze the fetus' red cells, their strength of reactivity must be tested, and the fetus' antigen status determined. After delivery, testing is performed to assess the extent of fetomaternal hemorrhage, as a large hemorrhage may require other therapeutic interventions. Another major role for immunohematological testing is to select blood components appropriately when intrauterine transfusion is required for fetal anemia resulting from maternal alloimmunization or some other cause. Supplementation with molecular methods has transformed the practice of immunohematology, particularly as it applies to typing for the D antigen of the Rh blood group system. Notwithstanding the advances in testing, close coordination and communication between the transfusion service and the obstetrics service are the foundation for ensuring the finest care for prenatal patients, and for new mothers and their infants. This review describes testing and transfusion practices for prenatal patients, using case presentations to highlight the management of selected immunohematological findings. It also includes a discussion of key patient management topics that are currently unresolved.

ABO hemolytic disease of the newborn: a need for clarity and consistency in diagnosis

The diagnosis of ABO hemolytic disease of the newborn (ABO HDN) has been the subject of considerable debate and clinical confusion. Its use as an overarching default diagnosis for hyperbilirubinemia in all ABO incompatible neonates regardless of serological findings is problematic and lacks diagnostic precision. Data on hemolysis indexed by carbon monoxide (CO) levels in expired air (ETCOc) and blood (COHbc) support an essential role for a positive direct antiglobulin test (DAT) in making a more precise diagnosis of ABO HDN. A working definition that includes ABO incompatibility, significant neonatal hyperbilirubinemia, and a positive DAT is needed to gain clarity and consistency in the diagnosis of ABO HDN. Absent a positive DAT, the diagnosis of ABO HDN is suspect. Instead, a negative DAT in a severely hyperbilirubinemic ABO incompatible neonate should trigger an exhaustive search for an alternative cause, a search that may require the use of targeted gene panels.

Early indicators of neonatal-onset hereditary thrombotic thrombocytopenia purpura

Background

Neonatal‐onset hereditary thrombotic thrombocytopenia purpura (hTTP) is often misdiagnosed due to its rarity. It begins with jaundice, similar to infants with ABO incompatibility.

Objective

To explore early indicators of neonatal‐onset hTTP.

Methods

This study was a retrospective case series of newborns with hTTP and ABO incompatibility. We compared the clinical characteristics and laboratory test results in these two groups.

Results

This study included four hTTP patients and 20 ABO‐incompatible newborns. All patients manifested disease during the neonatal period. There were equal numbers of males and females in each group. hTTP newborns showed earlier (median difference, 57.0 h; 95% confidence interval [CI], 24.0–65.0) and more severe hyperbilirubinemia (mean difference, 8.0 mg/dl; 95% CI, 3.8–12.1) than ABO‐incompatible newborns. In hTTP newborns, anemia was more common within 7 days after birth than in ABO‐incompatible newborns (odds ratio, 25.4; 95% CI, 1.2–551.6), and platelet counts were lower than in ABO‐incompatible newborns (17 ± 12 × 10⁹/L vs. 291 ± 76 × 10⁹/L). The levels of serum creatinine (median difference, 51.8 μmol/L; 95% CI, 16.0–109.4) and blood urea nitrogen (median difference, 5.7 mmol/L; 95% CI, 2.8–38.7) were higher in hTTP newborns than in ABO‐incompatible newborns. There were no significant differences in white blood cell counts, C‐reactive protein, alanine aminotransferase, or albumin levels.

Conclusions

Severe jaundice soon after birth, early anemia, and severe thrombocytopenia were more common in newborns with hTTP than ABO incompatibility. These are distinguishing early features of hTTP.

The spectrum of ABO haemolytic disease of the fetus and newborn in neonates born to group O mothers

BACKGROUND AND OBJECTIVES

ABO haemolytic disease of the fetus and newborn (HDFN) is a lesser recognized entity; however, the severity may vary in neonates. This prospective observational study was performed to determine the severity and risk of ABO-HDFN in neonates born to O group mothers.

MATERIALS AND METHODS

A total of 260 neonates born to non-alloimmunized blood group O mothers were recruited. Blood group O neonates were excluded from the study. Neonatal direct antiglobulin test (DAT) was performed using the column agglutination technique. They were monitored for clinical and laboratory parameters and followed up at 6-8 weeks. The maternal anti-A and anti-B titres (IgM and IgG) were also done.

RESULTS

A total of 176 neonates with blood group A (77/260; 29.6%) and B (99/260; 38.1%) were finally included in the study, and 15 (8.5%) of them were DAT positive. Overall, 26.7% (47/176) neonates received phototherapy, 172 (97.7%) survived and none required readmission. The median (inter-quartile range [IQR]) maternal IgG anti-B titre (32 [32-64]) was significantly higher (p < 0.001) than the IgG anti-A titre (16 [8-64]). The maximum total serum bilirubin in neonates had a significant positive association with neonatal birth weight (p = 0.045), positive DAT (p = 0.006) and requirement of phototherapy (p < 0.001). The relative risk (95% CI) of a DAT-positive neonate requiring phototherapy was 4.55 (3.12-6.33).

CONCLUSION

The frequency of ABO incompatibility in neonates born to group O mothers was 67.69% (176/260). The maternal IgG titre of ≥64 could be a good predictor for identifying the neonates at risk of developing hyperbilirubinaemia requiring phototherapy.

ABO haemolytic disease of the newborn: Improved prediction by novel integration of causative and protective factors in newborn and mother

BACKGROUND AND OBJECTIVES

Prediction of haemolytic disease of the foetus and newborn (HDFN) caused by maternal anti-A/-B enables timely therapy, thereby preventing the development of kernicterus spectrum disorder. However, previous efforts to establish accurate prediction methods have been only modestly successful.

MATERIALS AND METHODS

In a case-control study, we examined 76 samples from mothers and 76 samples from their newborns; 38 with and 38 without haemolysis. The IgG subclass profile of maternal anti-A and anti-B was determined by flow cytometry. Samples from newborns were genetically analysed for the A² subgroup, secretor and FcγRIIa receptor alleles.

RESULTS

Surprisingly, we found a correlation between the newborn secretor allele and haemolysis (p = 0.034). No correlation was found for FcγRIIa alleles. The A² subgroup was found only in newborns without haemolysis. Unexpectedly, different reaction patterns were found for maternal anti-A and anti-B; consequently, the results were treated separately. For the prediction of haemolysis in A-newborns, the maternal IgG1 subclass determination resulted in an accuracy of 83% at birth. For B-newborns, an accuracy of 91% was achieved by the maternal IgG2 subclass determination.

CONCLUSION

We improved the prediction of ABO-HDFN by characterizing maternal anti-A and anti-B by flow cytometry and we presented genetic traits in newborns with correlation to haemolysis. We propose a new understanding of A- and B-substances as immunogens that enhance the maternal immune response and protect the newborn, and we suggest that the development of ABO-HDFN is different when caused by maternal anti-A compared to maternal anti-B.