Transcutaneous bilirubinometry for detecting jaundice in term or late preterm neonates

BACKGROUND

The American Academy of Pediatrics and the Canadian Paediatric Society both advise that all newborns should undergo bilirubin screening before leaving the hospital, and this has become the standard practice in both countries. However, the US Preventive Task Force has found no strong evidence to suggest that this practice of universal screening for bilirubin reduces the occurrence of significant outcomes such as bilirubin-induced neurologic dysfunction or kernicterus.

OBJECTIVES

To evaluate the effectiveness of transcutaneous screening compared to visual inspection for hyperbilirubinemia to prevent the readmission of newborns (infants greater than 35 weeks' gestation) for phototherapy.

SEARCH METHODS

We searched CENTRAL, MEDLINE, Embase, CINAHL, ClinicalTrials.gov, ICTRP, and ISRCTN in June 2023. We also searched conference proceedings, and the reference lists of included studies.

SELECTION CRITERIA

We included randomized controlled trials (RCTs), quasi-randomized, cluster-randomized, or prospective cohort studies with control arm that evaluated the use of transcutaneous bilirubin (TcB) screening for hyperbilirubinemia in newborns before hospital discharge.

DATA COLLECTION AND ANALYSIS

We used standard methodologic procedures expected by Cochrane. We evaluated treatment effects using a fixed-effect model with risk ratio (RR) and 95% confidence intervals (CI) for categorical data and mean, standard deviation (SD), and mean difference (MD) for continuous data. We used the GRADE approach to evaluate the certainty of evidence.

MAIN RESULTS

We identified one RCT (1858 participants) that met our inclusion criteria. The study included 1858 African newborns at 35 weeks' gestation or greater who were receiving routine care at a well-baby nursery, and were randomly recruited prior to discharge to undergo TcB screening. The study had good methodologic quality. TcB screening versus visual assessment of hyperbilirubinemia in newborns: - may reduce readmission to the hospital for hyperbilirubinemia (RR 0.25, 95% CI 0.14 to 0.46; P < 0.0001; moderate-certainty evidence); - probably has little or no effect on the rate of exchange transfusion (RR 0.20, 95% CI 0.01 to 14.16; low-certainty evidence); - may increase the number of newborns who require phototherapy prior to discharge (RR 2.67, 95% CI 1.56 to 4.55; moderate-certainty evidence). - probably has little or no effect on the rate of acute bilirubin encephalopathy (RR 0.33, 95% CI 0.01 to 8.18; low-certainty evidence). The study did not evaluate or report cost of care.

AUTHORS' CONCLUSIONS

Moderate-certainty evidence suggests that TcB screening may reduce readmission for hyperbilirubinemia compared to visual inspection. Low-certainty evidence also suggests that TcB screening probably has little or no effect on the rate of exchange transfusion compared to visual inspection. However, moderate-certainty evidence suggests that TcB screening may increase the number of newborns that require phototherapy before discharge compared to visual inspection. Low-certainty evidence suggests that TcB screening probably has little or no effect on the rate of acute bilirubin encephalopathy compared to visual inspection. Given that we have only identified one RCT, further studies are necessary to determine whether TcB screening can help to reduce readmission and complications related to neonatal hyperbilirubinemia. In settings with limited newborn follow-up after hospital discharge, identifying newborns at risk of severe hyperbilirubinemia before hospital discharge will be important to plan targeted follow-up of these infants.

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..

Advances to diminish global newborn kernicterus mortality

OBJECTIVE

Initiatives, "Every Newborn Action Plans" and "Sustainable Developmental Goals," are profoundly shaping global infant mortality trends. Concurrently, professional organizations recommended curricula to prevent extreme hyperbilirubinemia (EHB) sequelae. Therefore we assessed if these efforts have successfully decreased EHB-related mortality over time.

STUDY DESIGN

We used the Global Burden of Diseases 2019 database to determine neonatal and infant mortality and the burden of kernicterus from 1990-2019.

RESULTS

Globally, kernicterus accounted for 2.8 million infant deaths and trended downwards significantly from 1990 to 2019. By 2019, kernicterus-related mortality was 4 and 293 per million livebirths in high (HICs) and low income countries (LICs), respectively. 82% of deaths occurred in LICs and lower-middle income-countries. Average declines of mortality rates were 6.2% and 3.0% for HICs and LICs, respectively.

CONCLUSIONS

Kernicterus-related mortality has been effectively reduced to <5 per million in HICs. Skills and knowledge transfer can potentially transform frontline services to bridge discordant kernicteric outcomes worldwide.

A "Gold Standard" Test for Diagnosing and Quantifying Hemolysis in Neonates and Infants

Identifying "gold standard" diagnostic tests can promote evidence-based neonatology practice. Hemolysis is a pathological shortening of the erythrocyte lifespan, differing from erythrocyte senescence in responsible mechanisms and clinical implications. Diagnosing hemolysis goes beyond a binary (yes vs. no) determination. It is characterized according to magnitude, and as acute vs. chronic, and genetically based vs. not. For neonates with significant hyperbilirubinemia or anemia, detecting hemolysis and quantifying its magnitude provides diagnostic clarity. The 2022 American Academy of Pediatrics (AAP) Clinical Practice Guideline on management of hyperbilirubinemia in the newborn states that hemolysis is a risk factor for developing significant hyperbilirubinemia and neurotoxicity. The guideline recommends identifying hemolysis from any cause, but specific guidance is not provided. A spectrum of laboratory tests has been endorsed as diagnostic methods for hemolysis. Herein we examine these laboratory tests and recommend one as the "gold standard" for diagnosing and quantifying hemolysis in neonates and infants.

Transcutaneous bilirubinometry versus total serum bilirubin measurement for newborns

BACKGROUND

Jaundice is a very common condition in newborns, affecting up to 60% of term newborns and 80% of preterm newborns in the first week of life. Jaundice is caused by increased bilirubin in the blood from the breakdown of red blood cells. The gold standard for measuring bilirubin levels is obtaining a blood sample and processing it in a laboratory. However, noninvasive transcutaneous bilirubin (TcB) measurement devices are widely available and used in many settings to estimate total serum bilirubin (TSB) levels.

OBJECTIVES

To determine the diagnostic accuracy of transcutaneous bilirubin measurement for detecting hyperbilirubinaemia in newborns.

SEARCH METHODS

We searched CENTRAL, MEDLINE, Embase, CINAHL and trial registries up to 18 August 2022. We also checked the reference lists of all included studies and relevant systematic reviews for other potentially eligible studies.

SELECTION CRITERIA

We included cross-sectional and prospective cohort studies that evaluated the accuracy of any TcB device compared to TSB measurement in term or preterm newborn infants (0 to 28 days postnatal age). All included studies provided sufficient data and information to create a 2 × 2 table for the calculation of measures of diagnostic accuracy, including sensitivities and specificities. We excluded studies that only reported correlation coefficients.

DATA COLLECTION AND ANALYSIS

Two review authors independently applied the eligibility criteria to all citations from the search and extracted data from the included studies using a standard data extraction form. We summarised the available results narratively and, where possible, we combined study data in a meta-analysis.

MAIN RESULTS

We included 23 studies, involving 5058 participants. All studies had low risk of bias as measured by the QUADAS 2 tool. The studies were conducted in different countries and settings, included newborns of different gestational and postnatal ages, compared various TcB devices (including the JM 101, JM 102, JM 103, BiliChek, Bilitest and JH20-1C) and used different cutoff values for a positive result. In most studies, the TcB measurement was taken from the forehead, sternum, or both. The sensitivity of various TcB cutoff values to detect significant hyperbilirubinaemia ranged from 74% to 100%, and specificity ranged from 18% to 89%.

AUTHORS' CONCLUSIONS

The high sensitivity of TcB to detect hyperbilirubinaemia suggests that TcB devices are reliable screening tests for ruling out hyperbilirubinaemia in newborn infants. Positive test results would require confirmation through serum bilirubin measurement.

Chemoprevention of bilirubin encephalopathy with a nanoceutical agent

BACKGROUND

Targeted rapid degradation of bilirubin has the potential to thwart incipient bilirubin encephalopathy. We investigated a novel spinel-structured citrate-functionalized trimanganese tetroxide nanoparticle (C-Mn3O4 NP, the nanodrug) to degrade both systemic and neural bilirubin loads.

METHOD

Severe neonatal unconjugated hyperbilirubinemia (SNH) was induced in neonatal C57BL/6j mice model with phenylhydrazine (PHz) intoxication. Efficiency of the nanodrug on both in vivo bilirubin degradation and amelioration of bilirubin encephalopathy and associated neurobehavioral sequelae were evaluated.

RESULTS

Single oral dose (0.25 mg kg-1 bodyweight) of the nanodrug reduced both total serum bilirubin (TSB) and unconjugated bilirubin (UCB) in SNH rodents. Significant (p < 0.0001) UCB and TSB-degradation rates were reported within 4-8 h at 1.84 ± 0.26 and 2.19 ± 0.31 mg dL-1 h-1, respectively. Neural bilirubin load was decreased by 5.6 nmol g-1 (p = 0.0002) along with improved measures of neurobehavior, neuromotor movements, learning, and memory. Histopathological studies confirm that the nanodrug prevented neural cell reduction in Purkinje and substantia nigra regions, eosinophilic neurons, spongiosis, and cell shrinkage in SNH brain parenchyma. Brain oxidative status was maintained in nanodrug-treated SNH cohort. Pharmacokinetic data corroborated the bilirubin degradation rate with plasma nanodrug concentrations.

CONCLUSION

This study demonstrates the in vivo capacity of this novel nanodrug to reduce systemic and neural bilirubin load and reverse bilirubin-induced neurotoxicity. Further compilation of a drug-safety-dossier is warranted to translate this novel therapeutic chemopreventive approach to clinical settings.

IMPACT

None of the current pharmacotherapeutics treat severe neonatal hyperbilirubinemia (SNH) to prevent risks of neurotoxicity. In this preclinical study, a newly investigated nano-formulation, citrate-functionalized Mn3O4 nanoparticles (C-Mn3O4 NPs), exhibits bilirubin reduction properties in rodents. Chemopreventive properties of this nano-formulation demonstrate an efficacious, efficient agent that appears to be safe in these early studies. Translation of C-Mn3O4 NPs to prospective preclinical and clinical trials in appropriate in vivo models should be explored as a potential novel pharmacotherapy for SNH.

A New Hour-Specific Serum Bilirubin Nomogram for Neonates ≥35 Weeks of Gestation

OBJECTIVE

To develop a statistically rigorous, hour-specific bilirubin nomogram for newborns based on a very large data set; and use it prospectively as a replacement for the 1999 Bhutani nomogram.

STUDY DESIGN

This was a retrospective analysis of first total serum bilirubin (TSB) measurements from 15 years of universal bilirubin screening during birth hospitalizations at 20 Intermountain Healthcare hospitals. Hour-specific TSB values were assembled into a nomogram by percentile, and subgroups were compared.

RESULTS

The information obtained included robust data in the first 12 hours after birth (which was not included in the 1999 nomogram), general agreement with the 1999 nomogram for values in the first 60 hours, but higher 75th and 95th percentile TSB values thereafter in the new version, no difference in TSB between male and female infants, higher TSB values among earlier gestation neonates (35^0/7-36^6/7 weeks vs ≥37 weeks, P < .0001), and lower TSB values in neonates of Black race (P < .0001) and higher values in neonates of Asian race (P < .001).

CONCLUSIONS

An updated and more informative Bhutani neonatal bilirubin nomogram, based on 140 times the number of subjects included the 1999 version, is now in place in our health care system.

Economic evaluation of point of care universal newborn screening for glucose-6-Phosphate dehydrogenase deficiency in United States

BACKGROUND AND OBJECTIVES

Glucose-6-Phosphate Dehydrogenase (G6PD) deficiency is frequent inherited enzymopathy that poses potentially preventable risk for extreme hyperbilirubinemia (EHB) which can, rarely, lead to acute bilirubin encephalopathy, childhood kernicterus and death. We aimed to estimate quality adjusted life years (QALY) lost due to G6PD deficiency associated with EHB and economic costs to best estimate value of universal pre-discharge screening.

METHODS

We did a cost utility analysis for US birth cohort utilizing pre-discharge screening decision tree model to estimate population burden and EHB outcomes, based on literature search and expert opinions. Employing human capital approach, we measured health benefits in terms of QALYs and economic losses. QALYs and costs were discounted at 3%; one-way sensitivity analysis was used for decision variables.

RESULTS

We determined for USA live births of 3.86 million in 2017, 1464 cases of EHB were estimated to be due to G6PD deficiency (CI 95%; range: 1270-1656) and contributed 2 deaths (CI 95%; range 1.3-3.2) and 14 (CI 95%; range: 9.1-21.5) cases of kernicterus. Over lifetime horizon, the model predicted undiscounted and discounted gains of 165 (102-252) life years; 241 (183-433) QALYs and 16 (9.9-24.5) life years; 89 (67.9-160.5) QALYs, respectively. Assuming 50% effectiveness, benefit cost ratios ranged from 0.19 to 3.42 for diverse operational settings. The cost to prevent a single case of kernicterus was $2.7 to 6.8 million per annum with cost per QALY gained at $35,946 to $89,159.

CONCLUSION

At incremental cost-effective threshold of $100,000/life year, pre-discharge screening would be expected to prove cost effective in preventing EHB related morbidities and mortality attributed to G6PD deficiency.

Does provider access to technology improve health care? Evidence from a national distribution of phototherapy in Rwanda

This study assessed a large-scale national distribution of phototherapy (PT) for infants at risk for severe hyperbilirubinemia. We combined healthcare data for infants with jaundice (using local clinical definitions) with a randomized roll-out of PT devices to estimate the causal effect of the national distribution. Pre-intervention, <3.0% of infants were diagnosed as jaundiced, 41.7% of these infants were not tested for bilirubin, and 17.5% and 34.3% were treated with direct sunlight or standard PT, respectively. We found that providing hospitals with PT devices increased care practices: infants with jaundice were more likely to receive PT [+6.26 percentage points (pp)], and less likely to receive sunlight (-6.96 pp) or standard (irradiance < 30 µW/cm²/nm) PT (-14.0 pp). However, the intervention did not affect the low diagnosis rate. Our findings suggest that complementary investments in improving diagnosis and monitoring of bilirubin levels increases the benefits of expanding provider access to PT devices.

Neonatal hyperbilirubinemia management: Clinical assessment of bilirubin production

The predominant cause of elevated total/plasma bilirubin (TB) levels is from an increase in bilirubin production primarily because of ongoing hemolysis. If undiagnosed or untreated, the risk for developing extreme neonatal hyperbilirubinemia and possibly bilirubin-induced neurological dysfunction (BIND) is increased. Since carbon monoxide (CO) and bilirubin are produced in equimolar amounts during the heme catabolic process, measurements of end-tidal CO levels, corrected for ambient CO (ETCOc) can be used as a direct indicator of ongoing hemolysis. A newly developed point-of-care ETCOc device has been shown to be a useful for identifying hemolysis-associated hyperbilirubinemia in newborns. This review summarizes the biology of bilirubin production, the clinical utility of a novel device to identify neonates undergoing hemolysis, and a brief introduction on the use of ETCOc measurements in a cohort of neonates in China.

A novel point-of-care device for measuring glucose-6-phosphate dehydrogenase enzyme deficiency

Extreme hyperbilirubinemia can cause bilirubin neurotoxicity. Infants with glucose-6-phosphate dehydrogenase (G6PD) deficiency can develop hemolysis and thus are at high risk. We evaluated a device that quantitatively measures G6PD activity kinetically using digital microfluidics (DMF). Intra- and inter-instrument and -day imprecision (CVs) were first assessed. G6PD activity in 86 samples was then measured and compared between DMF and 2 reference methods. Overall DMF reproducibility was 3.8% over 5 days by 2 operators on 2 instruments. Mean intra- and inter-instrument variabilities were 3.6% and 3.9%, respectively (n = 28), with a user variability of 4.3%. Mean G6PD activity was 6.40±4.62 and 6.37±4.62 U/g hemoglobin for DMF and Reference Methods 1 (n = 46) and 12.15±3.86 and 11.48±1.55 for DMF and 2 (n = 40), respectively, and strongly correlated (r = 0.95 and 0.95) with mean biases of +0.04±2.90 and +0.67±1.55 for methods 1 and 2, respectively. The novel device could be used for early newborn G6PD screening.

Hour-Specific Total Serum Bilirubin Percentiles for Infants Born at 29-35 Weeks' Gestation

INTRODUCTION

As preterm infants are susceptible to hyperbilirubinemia, they require frequent close monitoring. Prior to initiation of phototherapy, hour-specific total serum bilirubin (TSB) percentile cut-points are lacking in these infants, which led to the current study.

METHODS

A multi-site retrospective cohort study of preterm infants born between January 2013 and June 2017 was completed at 3 NICUs in Ontario, Canada. A total of 2,549 infants born at 290/7-356/7 weeks' gestation contributed 6,143 pre-treatment TSB levels. Hour-specific TSB percentiles were generated using quantile regression, further described by degree of prematurity, and among those who subsequently received phototherapy.

RESULTS

Among all infants, at birth, hour-specific pre-treatment, TSB percentiles were 36.1 µmol/L (95% confidence interval [CI]: 34.3-39.3) at the 40th, 52.3 µmol/L (49.4-55.1) at the 75th, and 79.5 µmol/L (72.1-89.6) at the 95th percentiles. The corresponding percentiles were 39.3 μmol/L (35.9-43.2), 55.4 μmol/L (52.1-60.2), and 87.1 μmol/L (CI 70.5-102.4) prior to initiating phototherapy and 24.4 μmol/L (20.4-28.8), 35.3 μmol/L (31.1-41.5), and 52.0 μmol/L (46.1-62.4) among those who did not receive phototherapy. Among infants born at 29-32 weeks, pre-treatment TSB percentiles were 53.9 µmol/L (49.4-61.0) and 95.5 µmol/L (77.5-105.0) at the 75th and 95th percentiles, with respective values of 48.7 µmol/L (43.0-52.3), and 74.1 µmol/L (64.8-83.2) for those born at 33-35 weeks' gestation.

CONCLUSION

Hour-specific TSB percentiles, derived from a novel nomogram, may inform how bilirubin is described in preterm newborns. Further research of pre-treatment TSB levels is required before clinical consideration.

Early Hyperbilirubinemia in Neonates with Down Syndrome

OBJECTIVE

To compare total serum bilirubin (TSB) levels, phototherapy usage, and hospital readmission for jaundice among neonates with Down syndrome vs controls.

STUDY DESIGN

A retrospective cohort study using 15 years of multihospital data. We created control reference intervals (5th, median, and 95th percentiles) for initial TSB values hourly during the first days after birth, and determined the proportion of neonates with Down syndrome whose TSB exceeded the 95th percentile control interval. We determined the proportion with an initial TSB exceeding the upper control reference interval, the highest TSB recorded, the percentage of neonates receiving phototherapy, and the rate of hospital readmission for jaundice treatment.

RESULTS

We compared 357 neonates with Down syndrome with 377 368 controls. Compared with controls, those with Down syndrome had 4.7 times the risk (95% CI, 3.9-5.7; P < .0001) of an initial TSB exceeding the 95th percentile control interval (23.5% vs 5.0%), 8.9 times (95% CI, 8.1-9.8; P < .0001) the phototherapy usage (62.2% vs 7.0%), and 3.6 times (95% CI, 1.6-8.2; P = .0075) the readmission rate for jaundice (17.4 vs 4.8 per 1000 live births).

CONCLUSIONS

Neonates with Down syndrome have a substantial risk of early hyperbilirubinemia. The American Academy of Pediatrics currently advises obtaining an early screening complete blood count from neonates with Down syndrome. We submit that assessing their TSB is also advisable.

Sixty years of phototherapy for neonatal jaundice - from serendipitous observation to standardized treatment and rescue for millions

A breakthrough discovery 60 years ago by Cremer et al. has since changed the way we treat infants with hyperbilirubinemia and saved the lives of millions from death and disabilities. "Photobiology" has evolved by inquiry of diverse light sources: fluorescent tubes (wavelength range of 400-520 nm; halogen spotlights that emit circular footprints of light; fiberoptic pads/blankets (mostly, 400-550 nm range) that can be placed in direct contact with skin; and the current narrow-band blue light-emitting diode (LED) light (450-470 nm), which overlaps the peak absorption wavelength (458 nm) for bilirubin photoisomerization. Excessive bombardment with photons has raised concerns for oxidative stress in very low birthweight versus term infants treated aggressively with phototherapy. Increased emphasis on prescribing phototherapy as a "drug" that is dosed cautiously and judiciously is needed. In this historical review, we chronicled the basic to the neurotoxic components of severe neonatal hyperbilirubinemia and the use of standardized interventions.

Frequency-following response among neonates with progressive moderate hyperbilirubinemia

OBJECTIVE

To evaluate the feasibility of auditory monitoring of neurophysiological status using frequency-following response (FFR) in neonates with progressive moderate hyperbilirubinemia, measured by transcutaneous (TcB) levels.

STUDY DESIGN

ABR and FFR measures were compared and correlated with TcB levels across three groups. Group I was a healthy cohort (n = 13). Group II (n = 28) consisted of neonates with progressive, moderate hyperbilirubinemia and Group III consisted of the same neonates, post physician-ordered phototherapy.

RESULT

FFR amplitudes in Group I controls (TcB = 83.1 ± 32.5µmol/L; 4.9 ± 1.9 mg/dL) were greater than Group II (TcB = 209.3 ± 48.0µmol/L; 12.1 ± 2.8 mg/dL). After TcB was lowered by phototherapy, FFR amplitudes in Group III were similar to controls. Lower TcB levels correlated with larger FFR amplitudes (r = -0.291, p = 0.015), but not with ABR wave amplitude or latencies.

CONCLUSION

The FFR is a promising measure of the dynamic neurophysiological status in neonates, and may be useful in tracking neurotoxicity in infants with hyperbilirubinemia.

141 Total bilirubin rate of rise of in moderate preterm neonates: impact of gestational age

Background

As compared to term neonates, those &lt; 35 weeks gestation (wks GA) are at greater risk for both acute and chronic bilirubin encephalopathy (ABE, CBE). Among these with postnatal total bilirubin rate of rise, (TB ROR) at age 0 to 72 hours has been observed because of either loss placental elimination system or increased postnatal production due to hemolysis. The ranges are known to vary &gt; 8.5 umol/L/h in neonates with Rh disease to &gt;3.4 umol/L/h at the 95th percentile track of the hour-specific nomogram. TB ROR in healthy term neonates is &lt;3.4 umol/L/h.

Objectives

To determine the GA ranges on TB ROR to explore predictive TB ROR in preterm neonates who are more vulnerable with each &lt;35 wks GA.

Design/Methods

A multi-site observational study to quantify TB ROR in preterm infants between 28 to 35 weeks. 1804 infants born between January 2013- March 2018 at 28–35 wks GA from three canadian perinatal centres were included and those with Rh disease were excluded. Analysis included infants &gt;27 weeks with at least one TB prior to the initiation of treatment for severe hyperbilirubinemia treatment. Feeding patterns, birth history and maternal health conditions were documented.

Results

The TB ROR were compared by two prematurity GA groups (28–31 weeks and 32–35 weeks) then per individual gestational age in four time periods in hours, 0–24, 24–48, 48–96, and 96 -120 in 1049 preterm infants using 3065 TB samples. Infants &lt;28 weeks GA were excluded since they represented a more diverse population. TB ROR by prematurity groups over all was higher in 32–35 weeks group at 0–12 hours (3.85 umol/L/h) and 25–36 hours (2.81umol/L/h) and decreased at 49–72 hours (0.24umol/L/h) time period as compared to the less mature group.

Conclusion

Though TB ROR were of similar patterns between prematurity groups (28–31 weeks and 32–35 weeks) it was at higher rate of rise between 13–36 hours and decreasing from 36–72 hours, with a plateau after 72 hours of age. There was a significant difference in the magnitude of TB ROR between prematurity groups at 0–24 hours. Additional research into the clinical care impact on the TB ROR should be conducted to study impact of production and elimination.

The Neonatal Acute Bilirubin Encephalopathy Registry (NABER): Background, Aims, and Protocol

BACKGROUND

Acute bilirubin encephalopathy (ABE) is a potentially devastating condition that can lead to death or life-long neurodevelopmental handicaps. ABE is particularly tragic because it is, in theory, completely preventable. Progress toward its prevention has been hampered by the perception that the extreme hyperbilirubinemia giving rise to ABE typically has no clear causation, with the majority of previous cases being labeled as "idiopathic" neonatal jaundice.

OBJECTIVES

This research briefing is intended to inform readers of a new prospective study aimed at clarifying the causes of ABE. This is accomplished by identifying qualifying patients with ABE anywhere in the USA and then documenting their clinical characteristics and the results of testing 28 specific genetic associations in a web-based, institutional review board-approved, REDCap (research electronic data capture) deidentified registry.

METHODS

In this research briefing, we present an overview of ABE and discuss the problem that most patients in the past have been labeled as having "idiopathic" hyperbilirubinemia. We also present data supporting a new theory that most (perhaps all) ABE patients have mutations or polymorphisms in genes involved in bilirubin production or metabolism. We introduce a new registry seeking to enroll 100 neonates with ABE as a voluntary, deidentified database, with next generation sequencing of 28 genes involved in bilirubin production/metabolism provided to enrollees at no cost.

RESULTS AND CONCLUSIONS

The Neonatal Acute Bilirubin Encephalopathy Registry (NABER) study will correlate deidentified clinical and genetic data in order to clarify the underlying causes of hyperbilirubinemia in current ABE patients. We maintain that the improved understanding this study produces will constitute a needed step toward devising new clinical pathways and strategies for preventing ABE in neonates.