Technical Report: Diagnosis and Management of Hyperbilirubinemia in the Newborn Infant 35 or More Weeks of Gestation

Phototherapy Alters the Plasma Metabolite Profile in Infants Born Preterm with Hyperbilirubinemia

OBJECTIVE

To investigate the effects of gestational age (GA) and phototherapy on the plasma metabolite profile of preterm infants with neonatal hyperbilirubinemia (NHB).

STUDY DESIGN

From a cohort of prospectively enrolled infants born preterm (n = 92), plasma samples of very preterm (VPT; GA, 28 + 0 to 31 + 6 weeks, n = 27) and moderate/late preterm (M/LPT; GA, 32 + 0 to 35 + 6 weeks, n = 33) infants requiring phototherapy for NHB were collected prior to the initiation of phototherapy and 24 hours after starting phototherapy. An additional sample was collected 48 hours after starting phototherapy in a randomly selected subset (n = 30; VPT n = 15; M/LPT n = 15). Metabolite profiles were determined using ultraperformance liquid chromatography tandem mass spectroscopy. Two-way ANCOVA was used to identify metabolites that differed between GA groups and timepoints after adjusting for total serum bilirubin levels (false discovery rate q-value < 0.05). Top impacted pathways were identified using pathway over-representation analysis.

RESULTS

Phototherapy was initiated at lower total serum bilirubin (mean ± SD mg/dL) levels in VPT compared with M/LPT infants (7.3 ± 1.4 vs 9.9 ± 1.9, P < .01). We identified 664 metabolites that were significant for a phototherapy effect, 191 metabolites significant for GA, and 46 metabolites significant for GA × phototherapy interaction (false discovery rate q-value < 0.05). Longer duration phototherapy had a larger mean effect size (24 hours postphototherapy: d = 0.36; 48 hours postphototherapy: d = 0.43). Top pathways affected by phototherapy included membrane lipid metabolism, one-carbon metabolism, creatine biosynthesis, and oligodendrocyte differentiation.

CONCLUSION

Phototherapy alters the plasma metabolite profile more than GA in preterm infants with NHB, affecting pathways related to lipid and one-carbon metabolism, energy biosynthesis, and oligodendrocyte differentiation.

Managing neonatal hyperbilirubinemia: An updated guideline

ABSTRACT

More than 80% of newborn infants experience jaundice as a result of elevated bilirubin during the first few weeks after birth. In most cases, hyperbilirubinemia is physiologic, but persistent and extreme elevations can lead to serious long-term complications, such as kernicterus. To avoid these complications and help clinicians in the successful assessment, evaluation, and treatment of hyperbilirubinemia, the American Academy of Pediatrics updated its clinical practice guideline for neonatal hyperbilirubinemia. This article reviews the guideline and highlights significant updates, such as an elevation in the threshold for phototherapy and exchange transfusion, inclusion of gestational age, and removal of racially based norms.

Phototherapy to Prevent Severe Neonatal Hyperbilirubinemia in the Newborn Infant 35 or More Weeks of Gestation: Technical Report

OBJECTIVE

To summarize the principles and application of phototherapy consistent with the current 2022 American Academy of Pediatrics "Clinical Practice Guideline Revision for the Management of Hyperbilirubinemia in the Newborn Infant 35 or More Weeks of Gestation."

METHODS

Relevant literature was reviewed regarding phototherapy devices in the United States, specifically those that incorporate blue to blue-green light-emitting diode, fluorescent, halogen, or fiberoptic light sources, and their currently marketed indications.

RESULTS

The efficacy of phototherapy devices varies widely because of nonstandardized use of light sources and configurations and irradiance meters. In summary, the most effective and safest devices have the following characteristics: (1) incorporation of narrow band blue-to-green light-emitting diode lamps (∼460-490 nm wavelength range; 478 nm optimal) that would best overlap the bilirubin absorption spectrum; (2) emission of irradiance of at least 30 µW/cm2/nm (in term infants); and (3) illumination of the exposed maximal body surface area of an infant (35% to 80%). Furthermore, accurate irradiance measurements should be performed using the appropriate irradiance meter calibrated for the wavelength range delivered by the phototherapy device.

CONCLUSIONS

With proper administration of effective phototherapy to an infant without concurrent hemolysis, total serum or plasma bilirubin concentrations will decrease within the first 4 to 6 hours of initiation safely and effectively.

Neonatal phototherapy and risk of epilepsy-A Danish population based study

To evaluate the risk of epilepsy in children who received neonatal phototherapy. A cohort of live singletons born at a Danish hospital (2002-2016) with a gestational age ≥ 35 weeks. We used Cox regression to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) of epilepsy in children treated with neonatal phototherapy compared to children not treated with neonatal phototherapy in the general population, and in a subpopulation of children who had serum bilirubin measurement. Adjusted HRs (aHR) were computed using multivariable and propensity score matching models to take maternal and neonatal factors into consideration. Children were followed from day 29 after birth to diagnosis of epilepsy, death, emigration, or December 31, 2016. Among 65,365 children, 958 (1.5%) received neonatal phototherapy. Seven children (incidence rates (IRs): 10.8 /10,000 person-years) who received neonatal phototherapy and 354 children (IR: 7.7) who did not receive neonatal phototherapy were diagnosed with epilepsy. Neonatal phototherapy was not associated with an increased risk of epilepsy using the multivariable (aHR 0.95, 95% CI: 0.43-2.09) and propensity score matched (aHR 0.94, 95% CI: 0.39-2.28) models. In the subpopulation of 9,378 children with bilirubin measurement, 928 (9.9%) received neonatal phototherapy. In the analysis of the subpopulation in which bilirubin level and age at the time of bilirubin measurement were further taking into consideration, neonatal phototherapy was not associated with an increased risk of epilepsy using the multivariable (aHR 1.26, 95% CI: 0.54-2.97) and propensity score matched (aHR 1.24, 95% CI: 0.47-3.25) models,Conclusions: Neonatal phototherapy was not associated with an increased risk of epilepsy after taking maternal and neonatal factors into consideration. What is known: • A few studies have suggested that neonatal phototherapy for hyperbilirubinemia may increase the risk of childhood epilepsy. • Whether the observed associations contribute to hyperbilirubinemia, phototherapy, or underlying factors requires further investigation. What is new: • This study revealed no increased risk of epilepsy in children treated with neonatal phototherapy compared to children not treated with phototherapy after taking maternal and neonatal factors into consideration. • After further taking bilirubin level and age at the time of bilirubin measurement into consideration, neonatal phototherapy was not associated with an increased risk of epilepsy.

Management of Neonatal Hyperbilirubinemia: Shedding Light on the American Academy of Pediatrics 2022 Clinical Practice Guideline Revision

Neonatal hyperbilirubinemia is one of the most common conditions managed by pediatricians. Although many infants are affected, most will experience complete resolution without complication. Acute bilirubin encephalopathy and kernicterus are rare yet debilitating sequelae of severe hyperbilirubinemia that can be avoided through careful monitoring and treatment with phototherapy. Appropriate management of neonatal hyperbilirubinemia must balance the risks of these severe conditions with the effects of overtreatment. Released in 2022, the American Academy of Pediatrics revised the clinical practice guideline for the management of hyperbilirubinemia, which aims to provide that balance through updates to the previous guideline. This article will provide the reader with (1) an evidence-based harm and benefit analysis of the guideline, (2) an overview of key changes and clarifications made in the new guideline, and (3) a practical summary of guideline updates. [Pediatr Ann. 2024;53(6):e208-e216.].

Georacial Epidemiological Estimates of Glucose-6-Phosphate Dehydrogenase Deficiency among Newborns in the United States

OBJECTIVE

Glucose-6-phosphate dehydrogenase deficiency (G6PDd) is the most common inherited enzyme deficiency disorder worldwide and a major risk factor for the development of severe hyperbilirubinemia. Racial diversity of phenotypes and genotypes in affected individuals is likely to exist in the United States because of changing population demographics. The aim of the present study was to predict an empirical estimate of annual prevalence of G6PDd in newborns adjusted for geography (state of birth), maternal racial identity, and sex of the infant.

STUDY DESIGN

Birth statistics (2019) from National Center for Vital Statistics and CDC-WONDER data and race-specific prevalence of G6PDd in the United States were evaluated from published sources. We developed Simpson's diversity index (DI) for each State and correlated these to rates of G6PDd in neonates. Descriptive statistics including modeled prevalence and its association with DI were assessed using the Spearman's rho correlation test. We modeled state-specific prevalence for six states (California, Washington DC, Illinois, Massachusetts, New York, and Pennsylvania) using population-level allele frequencies and race, based on Hardy-Weinberg equilibrium.

RESULTS

We estimated 78,010 (95% confidence interval: 76,768-79,252) newborns had G6PDd at birth in 2019 with cumulative median prevalence of 17.3 (interquartile range: 12.4-23.2) per 1,000 live births for United States. A strong association was noted for DI and prevalence of G6PDd (p < 0.0005). Five states (Washington DC, Mississippi, Louisiana, Georgia, and Maryland) have the highest projected G6PDd prevalence, with a range of 35 to 48 per 1,000 live births. The probability of G6PDd for female heterozygotes, based on male prevalence, ranged from 1.1 to 7.5% for each cohort in the select six states.

CONCLUSION

States with diverse populations are likely to have higher rates of G6PDd. These prevalence estimates exceeded by several-fold when compared with disorders screened by existing state mandated newborn screening panels. These discrepancies are further confounded by known risk of severe neonatal hyperbilirubinemia that results with G6PDd and the life-long risk of hemolysis. Combined universal newborn predischarge screening for G6PDd and bilirubin could alert and guide a clinician's practices for parental education and closer medical surveillance during the vulnerable neonatal time period.

KEY POINTS

· G6PDd is a common X-linked disorder that can present with varied phenotypes among newborns.. · Prevalence of G6PDd and genotype distribution varies with sex, race, and ethnicity.. · We present regional race- and sex-based estimates of G6PDd in the United States..

Unbound Bilirubin and Acute Bilirubin Encephalopathy in Infants Born Late Preterm and Term with Significant Hyperbilirubinemia

OBJECTIVE

To compare the association of unbound bilirubin (UB), total serum bilirubin (TSB), and bilirubin:albumin molar ratio (BAMR) with acute bilirubin encephalopathy (ABE), as assessed by bilirubin-induced neurologic dysfunction (BIND) score, in infants with significant hyperbilirubinemia (TSB ≥20 mg/dL or underwent exchange transfusion).

STUDY DESIGN

In this prospective cohort study, infants ≥34 weeks of gestational age with significant hyperbilirubinemia during the first 2 postnatal weeks were eligible, unless they had craniofacial malformations, chromosomal disorders, TORCH (toxoplasmosis, other infections, rubella, cytomegalovirus and herpes simplex) infections, surgery, or a family history of congenital deafness. TSB, serum albumin, and UB were measured at hospital admission using the colorimetric, bromocresol green, and modified peroxidase method, respectively. Infants were evaluated on admission for ABE using a standardized neurologic examination and assigned a BIND score by trained physicians. Infants with a total BIND score of 0 were deemed to not have ABE, whereas those with a score ≥1 were deemed to have ABE.

RESULTS

A total of 151 infants were studied, among whom 37 (24.5%) had ABE. Of these, 19 had mild ABE (BIND score 1-3) and 18 had moderate-to-severe ABE (BIND score 4-9). On logistic regression, UB, but not TSB or BAMR, was associated with ABE (aOR 1.64; 95% CI 1.17-2.3). On ordered logistic regression, UB, but not TSB or BAMR, was associated with severity of ABE (aOR 1.76; 95% CI 1.28-2.4).

CONCLUSIONS

Our findings of the association between UB and ABE indicate that BIND scoring may be useful for evaluation of ABE in infants ≥34 weeks of gestational age.

Clinical value of combined predictors of RET%, γ-GT, LDH in the ABO neonatal hemolytic disease

Objective

The purpose of this study is to examine the prognostic significance of the amalgamated indicators, reticulocyte percentage (RET%), lactate dehydrogenase (LDH), and γ-Glutamyltransferase (γ-GT), in neonatal ABO hemolytic disease.

Methods

A total of 137 hospitalized children with pathological jaundice were included. Based on their medical conditions, they were categorized into two groups, hemolytic (67 cases) and non-hemolytic (70 cases). Pearson linear correlation and binary logistic multivariate analysis were used to analyze LDH, γ-GT, RET% and hemolysis. Furthermore, the predictive value of the combined predictors of RET%, LDH, and γ-GT on ABO neonatal hemolytic disease was evaluated using the ROC curve analysis.

Results

The laboratory indexes of the two groups were subject to analysis using binary logistic regression to identify suspicious influencing factors. The study revealed that RET%, LDH, and γ-GT were independent risk factors for hemolysis. Pearson linear correlation analysis indicated a positive correlation between LDH and γ-GT with RET% (r = 0.529, P < 0.01; r = 0.526, P = <0.01, respectively). Furthermore, the predictive value of each combined predictor was obtained using the ROC curve, and it was observed that combined predictor L (RET% + LDH + γ-GT)>L1 (RET% + LDH)>L2 (RET% + γ-GT).

Conclusion

Combined predictor L (RET% + LDH + γ-GT)demonstrate its optimal diagnostic efficacy, offering a novel approach towards diagnosing early-onset ABO hemolytic disease of the newborn.

Current advances in 2022: A critical review of selected topics by the Association for the Advancement of Blood and Biotherapies (AABB) Clinical Transfusion Medicine Committee

BACKGROUND

The Association for the Advancement of Blood and Biotherapies Clinical Transfusion Medicine Committee (CTMC) composes a summary of new and important advances in transfusion medicine (TM) on an annual basis. Since 2018, this has been assembled into a manuscript and published in Transfusion.

STUDY DESIGN AND METHODS

CTMC members selected original manuscripts relevant to TM that were published electronically and/or in print during calendar year 2022. Papers were selected based on perceived importance and/or originality. References for selected papers were made available to CTMC members to provide feedback. Members were also encouraged to identify papers that may have been omitted initially. They then worked in groups of two to three to write a summary for each new publication within their broader topic. Each topic summary was then reviewed and edited by two separate committee members. The final manuscript was assembled by the first and senior authors. While this review is extensive, it is not a systematic review and some publications considered important by readers may have been excluded.

RESULTS

For calendar year 2022, summaries of key publications were assembled for the following broader topics within TM: blood component therapy; infectious diseases, blood donor testing, and collections; patient blood management; immunohematology and genomics; hemostasis; hemoglobinopathies; apheresis and cell therapy; pediatrics; and health care disparities, diversity, equity, and inclusion.

DISCUSSION

This Committee Report reviews and summarizes important publications and advances in TM published during calendar year 2022, and maybe a useful educational tool.

The Genetics of Glucose-6-Phosphate-Dehydrogenase (G6PD) and Uridine Diphosphate Glucuronosyl Transferase 1A1 (UGT1A1) Promoter Gene Polymorphism in Relation to Quantitative Biochemical G6PD Activity Measurement and Neonatal Hyperbilirubinemia

Glucose-6-phosphate dehydrogenase (G6PD) deficiency and polymorphism in uridine diphosphate glucuronosyl transferase 1A1 (UGT1A1) were associated with significant neonatal hyperbilirubinemia (NHB) and increased risk for kernicterus. However, quantitative screening tests for G6PD enzyme activity proved unsatisfactory in estimating the risk for significant NHB, especially in heterozygous females that could present phenotype overlap between normal homozygotes, heterozygotes, and deficient homozygotes, resulting in a continuum of intermediate G6PD activity.

OBJECTIVE

To examine the association of genotype and phenotype in newborns with decreased G6PD activity and its relation to NHB.

STUDY DESIGN

Quantitative G6PD enzyme activities were measured on umbilical cord blood samples. After accepting parental consent, samples were analyzed for G6PD mutations and UGT1A1 gene polymorphisms (number of TA repeats in the UGT1A1 promoter). The associations to quantitative G6PD activity and bilirubin levels were assessed.

RESULTS

28 females and 27 males were studied. The Mediterranean mutation (NM_001360016.2(G6PD): c.563C>T (p.Ser188Phe)) was responsible for most cases of G6PD deficiency (20 hemizygous males, 3 homozygous and 16 heterozygous females). The association between this mutation, decreased G6PD activity and higher bilirubin levels was confirmed. Heterozygosity to 6/7 TA repeats in the UGT1A1 promoter was associated with increased NHB, especially in female newborns with G6PD deficiency. However, it seems that the interaction between G6PD deficiency, UGT1A1 promoter polymorphism, and NHB is more complex, possibly involving other genetic interactions, not yet described. Despite genotyping females with G6PD deficiency, the overlap between the upper range of borderline and the lower range of normal G6PD activity could not be resolved.

CONCLUSIONS

The results of this study highlight the possibility for future implementation of molecular genetic screening to identify infants at risk for significant NHB, especially UGT1A1 polymorphism in heterozygous females with borderline G6PD deficiency. However, further studies are needed before such screening could be applicable to daily practice.

Increasing utilisation of a rebound hyperbilirubinaemia calculator in two newborn nurseries

Neonatal hyperbilirubinaemia requiring phototherapy treatment is a common problem impacting the length of hospital stay and rates of hospital readmission. Previous guidelines included guidance for initiating phototherapy treatment but not for discontinuing phototherapy treatment during initial newborn admission.In response to dissatisfaction from trainees, staff and families regarding the variable approach to discontinuing phototherapy among attending nursery providers, we used quality improvement methodologies to increase utilisation of a rebound hyperbilirubinaemia calculator as a more consistent method for guiding the timing of phototherapy discontinuation. The aim was to increase utilisation of the rebound hyperbilirubinaemia calculator for newborns treated with phototherapy in two newborn nurseries to >90% within 2 years.Sequential interventions focused on increasing provider awareness of the rebound hyperbilirubinaemia calculator and making the calculator simple to access and use.At the university medical centre nursery, the use of the calculator increased from 8.7% to 100%, exceeding the project goal. In the community hospital nursery, there was a statistically significant increase in the rate of utilisation from 3.7% to 79.4%, but this fell slightly below the goal of >90%.Electronic Health Record integration, along with education and addition of prompts to providers, increased utilisation of a rebound hyperbilirubinaemia calculator as a consistent approach for guiding decisions about discontinuing phototherapy treatment in newborns.

Evaluation of Intravenous Immunoglobulin Administration for Hyperbilirubinemia in Newborn Infants with Hemolytic Disease

The primary objective of this research was to evaluate the use of intravenous immunoglobulin (IVIG) in infants with hemolytic disease, to assess compliance with the American Academy of Pediatrics (AAP) guideline recommendations, and to review the data on which the guidelines were based. This retrospective study evaluated all infants in the NICU (neonatal intensive care unit) who received IVIG between January 2018 and December 2020 (n = 71). Total serum bilirubin (TSB) levels surrounding the time of IVIG administration, rate of rise of bilirubin, and direct antiglobulin test (DAT) status were evaluated to determine the appropriateness of IVIG use based on the 2004 AAP recommendations that was current at the time of the study. Fifty-nine infants received IVIG for hyperbilirubinemia. Of them, 80% had an ABO mismatch, 19% had Rh mismatch, and 71% were DAT-positive. Phototherapy was started at an average of 7 h of age, and the first IVIG dose was administered at an average of 13 h of life; nearly 25% received a second IVIG dose. One infant (1.6%) met all three AAP guideline criteria of being DAT-positive, bilirubin within 3 of exchange level, and rising bilirubin despite intensive phototherapy. Twenty-five (42%) babies were DAT positive and met one of the other two criteria. Only 12% (n = 7) had a bilirubin within 3 of exchange level. Most infants who received IVIG for hyperbilirubinemia did not meet the AAP criteria, prompting us to develop an institution-specific IVIG clinical practice guideline. The 2022 AAP guideline was published after our study was completed, but it confirmed our belief that IVIG usage should be more restricted and the criteria more explicit.

[Interpretation of the 2022 American Academy of Pediatrics guidelines for the management of hyperbilirubinemia in newborn infants]

The American Academy of Pediatrics updated the guidelines for the management of hyperbilirubinemia in the newborn infants with a gestational age of ≥35 weeks in September 2022. Based on the evidence over the past 18 years, the guidelines are updated from the aspects of the prevention, risk assessment, intervention, and follow-up of hyperbilirubinemia in the newborn infants with a gestational age of ≥35 weeks. This article gives an interpretation of the key points in the guidelines, so as to safely reduce the risk of bilirubin encephalopathy and unnecessary intervention.