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

CONTEXT: Severe hyperbilirubinemia is associated with kernicterus. Informed guidance on hyperbilirubinemia management, including preventive treatment thresholds, is essential to safely minimize neurodevelopmental risk. OBJECTIVE: To update the evidence base necessary to develop the 2022 American Academy of Pediatrics clinical practice guideline for management of hyperbilirubinemia in the newborn infant ≥35 weeks' gestation. DATA SOURCE: PubMed. STUDY SELECTION: English language randomized controlled trials and observational studies. Excluded: case reports or series, nonsystematic reviews, and investigations focused on <35-weeks' gestation infants. DATA EXTRACTION: Topics addressed in the previous clinical practice guideline (2004) and follow-up commentary (2009) were updated with new evidence published through March 2022. Evidence reviews were conducted for previously unaddressed topics (phototherapy-associated adverse effects and effectiveness of intravenous immune globulin [IVIG] to prevent exchange transfusion). RESULTS: New evidence indicates that neurotoxicity does not occur until bilirubin concentrations are well above the 2004 exchange transfusion thresholds. Systematic review of phototherapy-associated adverse effects found limited and/or inconsistent evidence of late adverse effects, including cancer and epilepsy. IVIG has unclear benefit for preventing exchange transfusion in infants with isoimmune hemolytic disease, with a possible risk of harm due to necrotizing enterocolitis. LIMITATIONS: The search was limited to 1 database and English language studies. CONCLUSIONS: Accumulated evidence justified narrowly raising phototherapy treatment thresholds in the updated clinical practice guideline. Limited evidence for effectiveness with some evidence of risk of harm support the revised recommendations to limit IVIG use.

Cord blood bilirubin and prediction of neonatal hyperbilirubinemia and perinatal infection in newborns at risk of hemolysis

Abstract Objective To assess the accuracy of umbilical cord bilirubin values to predict jaundice in the first 48 h of life and neonatal infection. Method Newborn infants treated at a regional well-baby nursery born at ≥36 weeks of gestation were included in this retrospective cohort study. All infants born in a 3-year period from mothers with O blood type and/or Rh-negative were included and had the umbilical cord bilirubin levels measured. Hyperbilirubinemia in the first 48 h was defined as bilirubin levels above the phototherapy threshold. Neonatal infection was defined as any antibiotic treatment before discharge. Results A total of 1360 newborn infants were included. Two hundred and three (14.9%) newborn infants developed hyperbilirubinemia in the first 48 h of life. Hyperbilirubinemic infants had smaller birth weight, higher levels of umbilical cord bilirubin, a higher rate of infection and were more often direct antiglobulin test positive. Umbilical cord bilirubin had a sensitivity of 76.85% and a specificity of 69.58% in detecting hyperbilirubinemia in the first 48 h, with the cut-off value at 34 µmol/L. The area under the receiver operating characteristic curve was 0.80 (95% CI: 0.78-0.82). Umbilical cord bilirubin had a sensitivity of 27.03% and specificity of 91.31% in detecting perinatal infection. The area under the receiver operating characteristic (ROC) curve was 0.59 (95% CI: 0.57-0.63). Conclusions A positive correlation was found between umbilical cord bilirubin and hyperbilirubinemia in the first 48 h of life. Umbilical cord bilirubin is a poor marker for predicting neonatal infection.

Genetic Factors and Delayed TSB Monitoring and Treatment as Risk Factors Associated with Severe Hyperbilirubinemia in Term Neonates Admitted for Phototherapy.

OBJECTIVES: This study aimed to determine whether maternal-fetal blood group isoimmunization, breastfeeding, birth trauma, age when first total serum bilirubin (TSB) was measured, age of admission, and genetic predispositions to hemolysis [due to genetic variants of glucose-6-phosphate dehydrogenase (G6PD) enzyme], and reduced hepatic uptake and/or conjugation of serum bilirubin [due to genetic variants of solute carrier organic anion transporter protein family member 1B1 (SLCO1B1) and uridine diphosphate glucuronosyltransferase family 1 member A1 (UGT1A1)] were significant risk factors associated with severe neonatal hyperbilirubinemia (SNH, TSB ≥ 342µmol/l) in jaundiced term neonates admitted for phototherapy. METHODS: The inclusion criteria were normal term neonates (gestation ≥ 37 weeks). Parents/care-givers were interviewed to obtain data on demography, clinical problems, feeding practice and age when first TSB was measured. Polymerase chain reaction-restriction fragment length polymorphism method was used to detect common G6PD, UGT1A1 and SLCO1B1 variants on each neonate's dry blood specimens. RESULTS: Of 1121 jaundiced neonates recruited, 232 had SNH. Logistic regression analysis showed that age (in days) when first TSB was measured [adjusted odds ratio (aOR) = 1.395; 95% confidence interval (CI) 1.094-1.779], age (in days) of admission (aOR = 1.127; 95% CI 1.007-1.260) and genetic mutant UGT1A1 promoter A(TA)7TAA (aOR = 4.900; 95% CI 3.103-7.739), UGT1A1 c.686C>A (aOR = 6.095; 95% CI 1.549-23.985), SLCO1B1 c.388G>A (aOR = 1.807; 95% CI 1.242-2.629) and G6PD variants and/or abnormal G6PD screening test (aOR = 2.077; 95% CI 1.025-4.209) were significantly associated with SNH. CONCLUSION: Genetic predisposition, and delayed measuring first TSB and commencing phototherapy increased risk of SNH.

Consenso de hiperbilirrubinemia del primer trimestre de la vida / Consensus on hyperbilirubinemia of the first trimester of life

La presencia de ictericia en la etapa neonatal puede responder a diversas causas, desde situaciones fisiológicas hasta enfermedades graves. En los neonatos de término que persisten ictéricos más allá de los 14 días de vida, debe determinarse si la hiperbilirrubinemia es no conjugada o conjugada para establecer, a la brevedad, el plan de estudios etiológicos y la terapéutica correspondiente. La hiperbilirrubinemia conjugada (colestasis) refleja una disfunción hepática en la mayoría de los casos, cuyas consecuencias son alteraciones del flujo biliar secundarias a anormalidades estructurales o moleculares del hígado y/o del tracto biliar.Durante la última década, los nuevos estudios moleculares revolucionaron el abordaje de los pacientes colestáticos, lo que permitió el diagnóstico de diversas entidades genéticas. La etiología de la hiperbilirrubinemia del primer trimestre debe determinarse con urgencia, ya que, en muchos casos, el tratamiento instituido de modo precoz puede modificar sustancialmente la evolución de la enfermedad o salvar la vida del paciente.

Neonatal jaundice may be due to different causes, ranging from physiological conditions to severe diseases. In term neonates with persistent jaundice beyond 14 days of life, it should be determined whether hyperbilirubinemia is unconjugated or conjugated, in order to study the etiology and start early treatment. In the majority of cases, conjugated hyperbilirubinemia (cholestasis) is a sign of liver dysfunction possibly associated with alterations in the bile flow secondary to structural or molecular abnormalities of the liver and/or the biliary tract. Over the past decade, new molecular studies have revolutionized the approach of cholestatic patients, leading to the identification of different genetic entities. It is important to determine the etilogy of neonatal hyperbilirubinemia since in many cases early treatment will substantially improve morbidity and mortality.

Reliability of Total Bilirubin Measurements in Whole Blood from Preterm Neonates Using a Blood Gas Analyzer.

BACKGROUND: Blood gas analyses are usually required more frequently in preterm neonates than in term neonates. If total bilirubin (TB) levels in whole blood measured using a blood gas analyzer are reliable, blood sampling for total serum bilirubin (TSB) levels alone can be reduced in preterm neonates. We investigated the reliability of measuring TB levels in whole blood from preterm neonates using the latest generation blood gas analyzer. METHODS: TB measured on an ABL90 FLEX blood gas analyzer and TSB analyzed in the hospital laboratory were simultaneously analyzed. TB and TSB levels (300 data sets in 85 preterm neonates) were compared using linear regression and Bland-Altman difference plots. RESULTS: Concordance correlation coefficient analysis showed a strong relationship between TB and TSB levels (a CCC value of 0.94) with a Pearson's coefficient of 0.97 and a bias correction of 0.97. Bland-Altman difference p lots demonstrated that, on average, TB tended to underestimate the TSB, with a mean (95% confidence interval) bias of -0.7 (-0.6 to -0.8) mg/dL. CONCLUSIONS: Whole blood TB levels measured using an ABL90 FLEX are reliable and can lead to a reduction in blood sampling for TSB in preterm neonates.

Validation of transcutaneous bilirubin nomogram for identifying neonatal hyperbilirubinemia in healthy Chinese term and late-preterm infants: a multicenter study / Validação de um nomograma de bilirrubina transcutânea para identificação de hiperbilirrubinemia neonatal em neonatos a termo e pré-termo tardios saudáveis na China: um estudo multicêntrico

OBJECTIVE: to prospectively validate a previously constructed transcutaneous bilirubin (TcB) nomogram for identifying severe hyperbilirubinemia in healthy Chinese term and late-preterm infants. METHODS: this was a multicenter study that included 9,174 healthy term and late-preterm infants in eight hospitals of China. TcB measurements were performed using a JM-103 bilirubinometer. TcB values were plotted on a previously developed TcB nomogram, to identify the predictive ability for subsequent significant hyperbilirubinemia. RESULTS: in the present study, 972 neonates (10.6%) developed significant hyperbilirubinemia. The 40th percentile of the nomogram could identify all neonates who were at risk of significant hyperbilirubinemia, but with a low positive predictive value (PPV) (18.9%). Of the 453 neonates above the 95th percentile, 275 subsequently developed significant hyperbilirubinemia, with a high PPV (60.7%), but with low sensitivity (28.3%). The 75th percentile was highly specific (81.9%) and moderately sensitive (79.8%). The area under the curve (AUC) for the TcB nomogram was 0.875. CONCLUSIONS: this study validated the previously developed TcB nomogram, which could be used to predict subsequent significant hyperbilirubinemia in healthy Chinese term and late-preterm infants. However, combining TcB nomogram and clinical risk factors could improve the predictive accuracy for severe hyperbilirubinemia, which was not assessed in the study. Further studies are necessary to confirm this combination. .

OBJETIVO: validar de forma prospectiva um nomograma de bilirrubina transcutânea (BTc) para identificar hiperbilirrubinemia grave em neonatos a termo e pré-termo tardios saudáveis na China. MÉTODOS: foi realizado um estudo multicêntrico que incluiu 9174 neonatos a termo e pré-termo tardios saudáveis em oito unidades da China. Foram realizadas dosagens de BTc utilizando um bilirrubinômetro. Os valores de BTc foram traçados em um nomograma de BTc para identificara capacidade de predição de hiperbilirrubinemia significativa. RESULTADOS: 972 recém-nascidos (10,6%) desenvolveram hiperbilirrubinemia significativa. O percentil 40 de nosso nomograma pode identificar todos os recém-nascidos com risco de hiper-bilirrubinemia significativa, porém com baixo valor preditivo positivo (VPP) (18,9%). De 453 recém-nascidos acima do percentil 95, 275 recém-nascidos desenvolveram posteriormente hiperbilirrubinemia significativa, com VPP elevado (60,7%), porém com baixa sensibilidade (28,3%). O percentil de 75 foi altamente específico (81,9%) e moderadamente sensível (79,8%). A área sob a curva (ASC) de nosso nomograma de BTc foi de 0,875. CONCLUSÕES: este estudo validou o nomograma de BTc, que pode ser utilizado para prever hiperbilirrubinemia significativa em neonatos a termo e pré-termo tardios saudáveis na China. Contudo, combinar o nomograma de BTc e fatores de risco clínicos pode melhorar a precisãode predição da hiperbilirrubinemia grave, o que não foi avaliado neste estudo. São necessários estudos adicionais para confirmar essa combinação. .

Influence of bilirubin photoisomers on unbound bilirubin measurement in clinical settings.

BACKGROUND: Measured unbound bilirubin concentration is influenced by bilirubin photoisomers. Bilirubin photoisomers are produced even with only a slight light exposure, and clinical samples are inevitably exposed to light. The objective of the study was to evaluate the influence of bilirubin photoisomers on the measurement of unbound bilirubin using serum of jaundiced neonates during blue light phototherapy. METHODS: Five neonates treated with phototherapy for hyperbilirubinaemia were enrolled. The samples were taken 12 h after initiation of phototherapy. Samples were processed by irradiation with blue light, by indoor ceiling light, by both blue light and indoor ceiling light or shaded. Bilirubin subfractions, total bilirubin and unbound bilirubin were measured. RESULTS: Compared with the non-irradiated samples, the (EZ)-cyclobilirubin concentration and (ZE)-bilirubin/(ZZ)-bilirubin ratio significantly increased in the blue light-irradiated samples, the (ZE)-bilirubin/(ZZ)-bilirubin ratio significantly increased in the indoor ceiling light-irradiated samples, and the (EZ)-cyclobilirubin, (EZ)-bilirubin and (ZE)-bilirubin/(ZZ)-bilirubin ratio significantly increased in the samples irradiated with both lights. No change was noted in unbound bilirubin in any group. CONCLUSIONS: We consider that changes in bilirubin photoisomers induced by light exposure during clinical practice do not influence the measured unbound bilirubin concentration.

Estimación visual de la ictericia neonatal y detección del riesgo de hiperbilirrubinemia significativa / Visual estimate of clinical jaundice and detection of the risk of significant hyperbilirubinemia

La predicción del riesgo de hiperbilirrubinemia significativa a través de la medición de una bilirrubina previa al alta ha sido validada en neonatos. La estimación visual de la extensión de la ictericia es comúnmente usada para la decisión de la obtención de la prueba de bilirrubina. Determinar la confiabilidad de la evaluación visual de la ictericia en la detección del riesgo de hiperbilirrubinemia significativa. 123 neonatos fueron examinados antes del alta por un pediatra quien asignó la extensión de la ictericia según su progresión céfalo-caudal. Una medida simultánea de bilirrubina transcutánea fue hecha por otro observador. Luego se comparó la calificación del riesgo de hiperbilirrubinemia significativa por ambos métodos, a través de un nomograma clasificado por zonas de riesgo. Resultados: El porcentaje de coincidencia global en relación a la designación de riesgo por ambos métodos fue 73%, pero esta proporción decreció a 56,3% cuando se analizó sólo para las zonas de alto riesgo. De hecho, 18 (43,7%) de los 32 neonatos calificados de alto riesgo por la prueba transcutánea fueron erróneamente identificados por la evaluación visual como niños de bajo riesgo. A pesar de que la concordancia general entre la estimación visual de la ictericia y la bilirrubina real es aceptable, la confiabilidad de la valoración visual como el procedimiento primario para identificar el riesgo de una hiperbilirrubinemia significativa es limitada. La detección de la severidad de la ictericia debe basarse en otros métodos, como la medición de la bilirrubina sérica o transcutánea

Pre-discharge bilirrubin percentiles have proved to be useful in predicting which infants will develop significant neonatal hyperbilirubinemia. The extent of clinical jaundice is commonly used to decide when to take a sample test for serum bilirubin. To determine the reliability of visual assessment of jaundice in the identification of the risk of significant hyperbilirubinemia. Clinical estimate of cephalocaudal progression of jaundice was carried out by a pediatrician in 123 neonates. Transcutaneous bilirubin (TCB) was simultaneously measured by an independent observer. Measurements by both methods were plotted into a nomogram stratified by risk zones to determine their level of agreement as to the classification of the risk. General agreement between the two measurements was 73%. However, this proportion decreased to 56.3% when only high-risk zones were analyzed. In fact, 18 (43.7%) of the 32 infants with transcutaneous bilirubin levels in high-risk zones were missclasified as low-risk cases by visual estimate. Although there was good general agreement between clinical evaluation of jaundice and TCB, visual assessment was not fully reliable as a primary screening method to identify significant hyperbilirubinemia. Further means should be used to support decisions regarding this risk, such as serum bilirubin sampling or transcutaneous bilirubin

Hyperbilirubinemia and rapid fatal hepatic failure in severe combined immunodeficiency caused by adenosine deaminase deficiency (ADA-SCID).

Adenosin deaminase (ADA) deficiency is the cause for Severe Combined Immunodeficiency (SCID) in about 15% of patients with SCID, often presenting as T (-)B (-)NK (-)SCID. Treatment options for ADA-SCID are enzyme replacement, bone marrow transplantation or gene therapy. We here describe the first patient with ADA-SCID and fatal hepatic failure despite bone marrow transplantation from a 10/10 HLA identical related donor. As patients with ADA-SCID may be at yet underestimated increased risk for rapid hepatic failure we speculate whether hepatitis in ADA-SCID should lead to the immediate treatment with enzyme replacement by pegylated ADA.

The investigation of infants with RhD-negative mothers: can we safely omit the umbilical cord blood direct antiglobulin test?

Historically, the investigation of a neonate at risk of Rhesus D antigen (RhD)-associated haemolytic disease has included a direct antiglobulin test on umbilical cord blood. However, the introduction of routine antenatal anti-RhD prophylaxis has led to a significant number of false positive results and recent studies suggest that a positive cord blood direct antiglobulin test is poorly predictive of subsequent hyperbilirubinaemia. The British Committee for Standards in Haematology guidelines now recommend that a direct antiglobulin test should no longer be performed routinely on umbilical cord blood in infants born to RhD-negative mothers. We review the recent changes in antenatal management of RhD-negative mothers and their impact on the neonatal presentation of RhD-associated haemolytic disease of the newborn that underpin this recommendation. We conclude that there is convincing evidence to support the guidelines. Finally, we consider how babies born to RhD-negative mothers should be investigated and consider alternative strategies to detect neonatal hyperbilirubinaemia.

Yield of recommended blood tests for neonates requiring phototherapy for hyperbilirubinemia.

BACKGROUND: Hyperbilirubinemia of the newborn is common. Rarely is an underlying disease other than physiologic hyperbilirubinemia considered the cause of high bilirubin levels. Some of the laboratory tests recommended by the American Academy of Pediatrics are expensive and do not always lead to diagnosis. OBJECTIVE: To evaluate the efficacy of standard laboratory tests performed on newborn infants requiring phototherapy for hyperbilirubinaemia. METHODS: We conducted a retrospective chart review that included neonates born during a 6 month period with birth weight 2500 g treated with phototherapy for hyperbilirubinemia (n = 282) according to published guidelines. The main outcome measures were primary and maximal bilirubin values (mg/dl), time to jaundice (in days), the number of bilirubin tests undertaken and whether the patient showed abnormal functioning, and the number of days in follow-up. RESULTS: Thirty-three neonates (11.7%) were positive in at least one laboratory test (defined as "Abnormal" in our study), 45.5% of whom met the criteria for phototherapy during the first 48 hours of life. Among the newborns who were negative for all laboratory tests (defined as "Normal"), only 6.8% met phototherapy criteria within their first 48 hours of life (P < 0.001). In the Normal group there was a consistent decrease in total serum bilirubin values shortly after phototherapy was begun, while the Abnormal group presented an increase in serum bilirubin values during the first 12 hours of phototherapy. None of the infants had conjugated (direct) hyperbilirubinemia during the study period. CONCLUSIONS: Most neonates presenting with a laboratory identifiable etiology for hyperbilirubinemia (i.e., hemolysis) can be distinguished from those who test negative, mainly based on the timing of presentation and response to phototherapy. A more meticulous selection of patients and reduction in the magnitude of routine laboratory testing can safely reduce discomfort to infants with hyperbilirubinemia as well as costs.