Evaluation of Neonatal Hemolytic Jaundice: Clinical and Laboratory Parameters

Positive Direct Antiglobulin Test: Is It a Risk Factor for Significant Hyperbilirubinemia in Neonates with ABO Incompatibility?

OBJECTIVE

ABO blood group (ABO) incompatibility is a common cause of neonatal indirect hyperbilirubinemia. The direct antiglobulin test (DAT) can identify infants developing hemolytic disease. This study aims to evaluate the significance of DAT positivity among neonates with ABO incompatibility.

STUDY DESIGN

This retrospective study included 820 neonates with blood group A or B who were born to blood group O mothers. The study group consisted of neonates (n = 79) who had positive DAT, and the control group consisted of infants (n = 741) who had negative DAT. Demographic and clinical data of the neonates regarding jaundice were collected and compared statistically.

RESULTS

The bilirubin level at 24 hours of life (study group: 8 ± 2.6 mg/dL, control group: 6 ± 2.2 mg/dL, p < 0.001) and the highest bilirubin level (study group: 12.7 ± 3.6 mg/dL, control group: 10.4 ± 4.2 mg/dL, p < 0.001) were higher in infants with positive DAT. A total of 37 (46.8%) infants in the study group and 83 (11.2%) infants in the control group received phototherapy (PT) in the nursery (p < 0.001). In neonates with positive DAT, direct bilirubin level, duration of hospitalization, and PT in the nursery were higher (p = 0.002, <0.001, and <0.001, respectively), whereas hemoglobin level was lower (p < 0.001).

CONCLUSION

In neonates with ABO incompatibility, a positive DAT is a risk factor for developing significant hyperbilirubinemia. Close follow-up of newborn infants with ABO incompatibility is crucial for early detection and treatment of neonatal jaundice to avoid early and late complications.

KEY POINTS

· The clinical spectrum of ABO incompatibility varies widely.. · The ABO incompatibility with positive DAT are at greater risk for high bilirubin levels.. · Infants with blood group incompatibilities must be monitored closely..

Handheld diffuse reflectance spectroscopy system for noninvasive quantification of neonatal bilirubin and hemoglobin concentrations: a pilot study

The prevalence rate of neonatal jaundice can reach 80%, of which 5% may develop dangerous hemolytic jaundice. The blood test for obtaining bilirubin and hemoglobin concentration is the gold standard for diagnosing hemolytic jaundice; however, frequently drawing blood from jaundice neonates for the screening purpose is not practical. We have developed a handheld diffuse reflectance spectroscopy system to noninvasively determine the bilirubin and hemoglobin levels in neonates. Our study showed that the correlation coefficients were 0.95 and 0.80 for bilirubin and hemoglobin between the results from the blood tests and our handheld system, respectively. This handheld system could be an effective tool for screening hemolytic jaundice.

The development and validation of a predictive model for neonatal phototherapy outcome using admission indicators

Delayed exchange transfusion therapy (ETT) after phototherapy failure for newborns with severe hyperbilirubinemia could lead to serious complications such as bilirubin encephalopathy (BE). In this current manuscript we developed and validated a model using admission data for early prediction of phototherapy failure. We retrospectively examined the medical records of 292 newborns with severe hyperbilirubinemia as the training cohort and another 52 neonates as the validation cohort. Logistic regression modeling was employed to create a predictive model with seven significant admission indicators, i.e., age, past medical history, presence of hemolysis, hemoglobin, neutrophil proportion, albumin (ALB), and total serum bilirubin (TSB). To validate the model, two other models with conventional indicators were created, one incorporating the admission indicators and phototherapy failure outcome and the other using TSB decrease after phototherapy failure as a variable and phototherapy outcome as an outcome indicator. The area under the curve (AUC) of the predictive model was 0.958 [95% confidence interval (CI): 0.924-0.993] and 0.961 (95% CI: 0.914-1.000) in the training and validation cohorts, respectively. Compared with the conventional models, the new model had better predictive power and greater value for clinical decision-making by providing a possibly earlier and more accurate prediction of phototherapy failure. More rapid clinical decision-making and interventions may potentially minimize occurrence of serious complications of severe neonatal hyperbilirubinemia.

Is it necessary to add the eluate testing to the direct antiglobulin test to improve the detection of maternal erythrocyte alloantibodies?

BACKGROUND

The screening of umbilical cord blood samples by the Direct Antiglobulin Test (DAT) is the reference tool for the identification of maternal erythrocyte alloantibodies present in erythrocytes; however, its diagnostic usefulness is controversial.

OBJECTIVE

To evaluate the diagnostic validity, safety, and efficiency of the eluate testing (detection of antibody in erythrocyte eluates by the Indirect Antiglobulin Test/IAT) in cord blood samples for detection of maternal erythrocyte alloantibodies in comparison with the DAT.

MATERIALS AND METHODS

Evaluation study of diagnostic tests. DAT and eluate testing were performed in 306 cord blood samples from neonates born to mothers admitted at Clínica Somer in Rionegro, Colombia; then, antibodies present in the eluates were identified with erythrocyte panels. Percentage of positive results by DAT and IAT were compared with the Pearson's chi-square test and the agreement between both assays with the Cohen's kappa coefficient. The diagnostic sensitivity, specificity, safety, and efficiency of the eluate testing were calculated, taking into account the use of DAT as an imperfect reference test.

RESULTS

The DAT detected alloantibodies in 6.21% of samples and the eluate testing in 14.1 %; the strength of agreement between both tests was moderate (k = 0.56) due to 25 discrepancies. The eluate testing showed sensitivity and specificity of 98.83 % and 92.31 % respectively, and a negative predictive value of 99.9 %. The diagnostic efficiency was sufficient for detection of maternal erythrocyte alloantibodies. The antibodies identified in the erythrocyte eluates were anti-A or anti-B (79.5 %), anti-D (136%), anti-C (2,3%), and anti-Fya (2,3%).

CONCLUSION

The eluate testing in cord blood samples is a valid, safe, and efficient test for the diagnosis of maternal erythrocyte alloantibodies.

G6PD Deficiency Prevalence as a Cause of Neonatal Jaundice in a Neonatal Ward in Dohuk, Iraq

OBJECTIVE

The current study initiated to address the effect of glucose-6-phosphate dehydrogenase (G6PD) deficiency on the pathogenesis and the severity of neonatal hyperbilirubinemia (NHB).

STUDY DESIGN

A total of 100 newborns with moderate to severe indirect hyperbilirubinemia and 50 normal neonates without hyperbilirubinemia had been enrolled in the current case-control study. All enrolled neonates had been tested for ABO and Rh(D) blood grouping, Total serum bilirubin measurement, complete blood count, morphology, reticulocyte counts, direct Coombs' test, and G6PD enzyme assay.

RESULTS

From all enrolled hyperbilirubinemic neonates, 16% were G6PD deficient and this displays a statistically significant difference in comparison to controls (only 6% were G6PD deficient). Also, significant difference was found in the level of serum indirect bilirubin among G6PD-deficient neonate in comparison to G6PD nondeficient neonates which had contributed significantly to the difference in the duration of phototherapy and hospitalization among deficient neonate. Despite this, no significant difference found in the onset of presentation, reticulocytes count, and age of neonates between the two groups (G6PD-deficient and G6PD nondeficient neonates).

CONCLUSION

The current study augments the etiological role of G6PD in the causation and severity of NHB in the region; however, in the absence of significant difference in the reticulocytes and the hemoglobin level, the underlying mechanism cannot be backed to the excess hemolysis alone.

Indirect neonatal hyperbilirubinemia in hospitalized neonates on the Thai-Myanmar border: a review of neonatal medical records from 2009 to 2014

BACKGROUND

Indirect neonatal hyperbilirubinemia (INH) is a common neonatal disorder worldwide which can remain benign if prompt management is available. However there is a higher morbidity and mortality risk in settings with limited access to diagnosis and care. The manuscript describes the characteristics of neonates with INH, the burden of severe INH and identifies factors associated with severity in a resource-constrained setting.

METHODS

We conducted a retrospective evaluation of anonymized records of neonates hospitalized on the Thai-Myanmar border. INH was defined according to the National Institute for Health and Care Excellence guidelines as 'moderate' if at least one serum bilirubin (SBR) value exceeded the phototherapy threshold and as 'severe' if above the exchange transfusion threshold.

RESULTS

Out of 2980 records reviewed, 1580 (53%) had INH within the first 14 days of life. INH was moderate in 87% (1368/1580) and severe in 13% (212/1580). From 2009 to 2011, the proportion of severe INH decreased from 37 to 15% and the mortality dropped from 10% (8/82) to 2% (7/449) coinciding with the implementation of standardized guidelines and light-emitting diode (LED) phototherapy. Severe INH was associated with: prematurity (< 32 weeks, Adjusted Odds Ratio (AOR) 3.3; 95% CI 1.6-6.6 and 32 to 37 weeks, AOR 2.2; 95% CI 1.6-3.1), Glucose-6-phosphate dehydrogenase deficiency (G6PD) (AOR 2.3; 95% CI 1.6-3.3), potential ABO incompatibility (AOR 1.5; 95% CI 1.0-2.2) and late presentation (AOR 1.8; 95% CI 1.3-2.6). The risk of developing severe INH and INH-related mortality significantly increased with each additional risk factor.

CONCLUSION

INH is an important cause of neonatal hospitalization on the Thai-Myanmar border. Risk factors for severity were similar to previous reports from Asia. Implementing standardized guidelines and appropriate treatment was successful in reducing mortality and severity. Accessing to basic neonatal care including SBR testing, LED phototherapy and G6PD screening can contribute to improve neonatal outcomes.