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Objective: Neonates with hyperbilirubinemia are at risk of brain damage, and at least two-thirds of neonates show clinical signs of jaundice in the first week of life. To predict the correlation between cord carboxyhemoglobin (COHb) with postnatal 24th-hour total serum bilirubin (TSB) level in newborns with ABO incompatibility. Methods: This retrospective cohort study included newborns older than 35 weeks of gestation who were followed up in the Neonatal Intensive Care Unit of Tokat Gaziosmanpaşa University Hospital between January 2019 and December 2023. Patients were divided into three groups; Group 1: ABO incompatibility with direct Coombs (DC) positive newborns, Group 2: ABO incompatibility and DC negative newborns, and Group 3: ABO incompatibility with no known hemolysis risk factors. Results: A total of 292 patients in 3 groups were included in the study. Group 1 consisted of 93 patients, Group 2 consisted of 99, and Group 3 consisted of 100. The mean newborn cord COHb was 1.59±0.56%, the mean cord bilirubin was 3.12±2.05 mg/dL, the mean 24-h TSB was 6.40±1.99 mg/dL, and the mean cord blood gas hemoglobin was 18.06±2.57 g/dL. In the first group, the correlation between cord COHb and 24-h TSB was high and statistically significant. In the second group, the correlation between cord COHb and 24-h PTH was low and statistically significant. Conclusion: The use of COHb as a predictor of 24-h postnatal TSB levels in ABO-incompatible neonates is plausible.

Introduction: Glucose- 6-phosphate dehydrogenase deficiency is the most common enzymatic disorder of the red cell and an important risk factor for neonatal jaundice. Methodology: The aim of the study was to determine the incidence of G-6-PD deficiency among jaundiced neonates, and describe the associated morbidity and mortality pattern in them. A prospective cross sectional study was conducted and we studied one hundred consecutive jaundiced neonates (55 males, 45 females) presenting at Aminu Kano Teaching Hospital from between 2004 and August 2005. G-6-PD activity was assayed by Quantitative spectrophotometric method of Kornberg; serum bilirubin and haemoglobin levels were estimated by standard techniques. Exposure to possible Icterogenic agents, clinical features of kernicterus and the outcome were noted. Results: The incidence of G-6-PD deficiency was found to be 46% with male to female ratio of 3:1 (Χ 2 = 15, p = 0.001). A higher proportion (60.6%) of the inborn neonates had G-6-PD deficiency (x2 = 5.5, p = 0.06). Jaundice was noticed significantly earlier in the G-6-PD deficient neonates (mean = 2.0, SD = 1 days) compared to (mean = 2.7, SD = 1.6 days) in the sufficient neonates (t = 2.3, p = 0.02). Sixteen (16%) neonates developed kernicterus, of these 10 (63%) were G-6-PD deficient. The mortality rate among G-6-PD deficient neonates was 15% (7 of 46) twice as much as in the sufficient neonates 7% (4 of 54). Only six neonates 0.6% ware exposed to naphthalene of whom three were G -6PD deficient. Five babies were given traditional medicine two of which were G6-PD deficient. Conclusion: G-6-PD deficiency is an important risk factor for neonatal jaundice. Jaundice appeared early in the deficient neonates. There is high incidence of kernicterus and mortality among them. Low admission weight significantly contributed to the mortality.

Background Phototherapy (PT) for unconjugated hyperbilirubinaemia remains an important and invaluable intervention in the management of neonatal jaundice when appropriately and optimally employed. The efficiency of PT greatly depends on the irradiance of the device, which is measured using an irradiance meter. Available optimal phototherapy is a key desirable newborn service that should be offered and accessible in secondary and tertiary health care facilities. Objective: The study aimed at determining the availability and irradiance measure of phototherapy devices in neonatal units in Kaduna state, Northwestern Nigeria. Materials and Methods: The study was an action research survey of all hospitals providing newborn care in Kaduna state including public and private profit and nonprofit faith based facilities. Phototherapy devices in use in the facilities were documented (types, brand and bulbs). The average irradiance of PT device was measured using model 22 Olympic Bili – MeterTM at facility traditional PT distance and distance of optimal irradiance was also determined and documented. Facilities were introduced to and educated on protocols on neonatal jaundice and how to ensure optimization of irradiance and management of neonatal jaundice. Results: None of the 31 public secondary health care facilities operated a newborn unit nor provided management for neonatal jaundice. Overall 15 facilities provided PT services of which 87%were non-government facilities made up of 15% faith based and 85% private for profit facilities. Only 13.3% facilities had PT devices which offered irradiance (> 10 µW/cm2 / nm) suitable for conventional PT at the facilities’ traditional PT distance this however, increased to 7 (46.7%) facilities with adjusted distances. Only 3 (20%) facilities had devices that could offer intensive PT (irradiance > 30 µW/cm2 / nm) at varying distances. None of the surveyed facilities had a radiometer nor knew irradiance of their PT devices and neither did any have a written protocol for the management of neonatal jaundice. Expertise for and availability of exchange blood transfusion (EBT) services was available only in 26.7% of the facilities. Conclusions: Private health care facilities constitute a major provider of neonatal jaundice healthcare services however the services were grossly suboptimal and inadequate and will need significant and urgent improvement to enhance newborn health and indices.

Background: Exchange transfusion (ET) is an effective treatment for acute bilirubin encephalopathy and extreme neonatal hyperbilirubinemia (ENH). It can reduce mortality and morbidity. This study aimed to investigate the trends and risk factors of ENH requiring ET in hospitalized neonates in Iran.Methods: A retrospective analysis of medical records of neonates who underwent ET due to ENH was conducted from 2011 to 2021, in Shiraz, Iran. Clinical records were used to gather demographic and laboratory data. The quantitative data were expressed as mean±SD, and qualitative data was presented as frequency and percentage. P

Background: Neonatal hyperbilirubinemia (NH) affects over 80% of premature babies & 60% of fullterm babies in the first week of life. There are two forms of neonatal hyperbilirubinemia: conjugated & unconjugated. Unconjugated forms can cause bilirubin encephalopathy & kernicterus in extreme cases, while conjugated forms are thought to be a result of a systemic sickness. Babies born prematurely are at a higher risk of hyperbilirubinemia due to bilirubin-induced brain damage compared to their term counterparts. Aim and objectives: The study aims to assess the effect of phototherapy on liver enzymes, renal functions, in NH patients before and after phototherapy. Subjects and methods: This was an observational cross-sectional study that was performed at neonatal intensive care unit (NICU) Al-Hussein university hospital. It included 100 term infants of both sex that received phototherapy for management of neonatal indirect hyperbilirubinemia. When indicated according to Bhutani Nomogram curve. Result: There is no statistically significant difference was found between group I that treated by conventional phototherapy only and group II that treated by intensive then conventional phototherapy regarding maternal age, ABO blood groups and Rh status maternal comorbidities like gestational HTN or diabetes, gestational age, onset of jaundice. Also Both therapy groups reduced total and direct bilirubin significantly (Paired sample t test, P = 0.000). Group II had a greater total bilirubin reduction than group I (Independent sample t test, P = 0.001). Both therapy groups had significant ALT, AST, ALP, urea and creatinine reductions (Paired sample t test, P = 0.000). Conclusion: As regard the effect of Phototherapy on liver enzymes and kidney functions, our results showed a statistically significant reduction in ALT, AST, ALP, urea and creatinine in both treated groups. [ABSTRACT FROM AUTHOR]

Background: Exchange transfusion (ET) is an effective treatment for acute bilirubin encephalopathy and extreme neonatal hyperbilirubinemia (ENH). It can reduce mortality and morbidity. This study aimed to investigate the trends and risk factors of ENH requiring ET in hospitalized neonates in Iran. Methods: A retrospective analysis of medical records of neonates who underwent ET due to ENH was conducted from 2011 to 2021, in Shiraz, Iran. Clinical records were used to gather demographic and laboratory data. The quantitative data were expressed as mean±SD, and qualitative data was presented as frequency and percentage. P<0.05 was considered statistically significant. Results: During the study, 377 ETs were performed for 329 patients. The annual rate of ET decreased by 71.2% during the study period. The most common risk factor of ENH was glucose-6-phosphate dehydrogenase (G6PD) deficiency (35%), followed by prematurity (13.06%), ABO hemolytic disease (7.6%), sepsis (6.4%), Rh hemolytic disease (6.08%), and minor blood group incompatibility (3.34%). In 28.52% of the cases, the cause of ENH was not identified. 17 (5.1%) neonates had acute bilirubin encephalopathy, of whom 6 (35.29%) had G6PD deficiency, 6 (35.29%) had ABO incompatibility, and 2 (11.76%) had Rh incompatibility. Conclusion: Although the rate of ET occurrence has decreased, it seems necessary to consider different risk factors and appropriate guidelines for early identification and management of neonates at risk of ENH should be developed. The findings of the study highlighted the important risk factors of ENH in southern Iran, allowing for the development of appropriate prevention strategies. [ABSTRACT FROM AUTHOR]

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.] [ABSTRACT FROM AUTHOR]

Abstract Bilirubin is a metabolic product of heme, and an increase in its level may be toxic to the body. It may be conjugated or unconjugated. Encephalopathy is caused by unconjugated bilirubin has the ability to pass through the blood-brain barrier, entering the central nervous system. Conjugated forms of bilirubin result in biliary obstruction and a change in urine colour due to a decrease in excretion. Excessive hemolysis can result from hereditary and autoimmune diseases, deficient RBC membranes, enzyme deficiency, and hemoglobin structural anomalies. In this review, we summarize all the possible mechanisms and complications regarding bilirubin. Cellular and molecular functions and mechanisms of bilirubin are explained, followed by several complications viz neurotoxicity, auditory dysfunction, and nephrotoxicity. The cause of bilirubin-induced neuronal cell damage is likely due to the elevated levels of unconjugated bilirubin in plasma, mitochondrial, and endoplasmic reticulum (ER) membranes. These disruptions in the membranes could lead to harmful effects such as neuronal excitotoxicity, energy failure in mitochondria, or an increased concentration of calcium within the cells. At the cellular level, bilirubin exerts its toxic effect by disturbing the normal functioning of neuronal cells. Bilirubin's presence can cause certain inflammatory responses, resulting in the activation of proinflammatory cytokines. Additionally, research has demonstrated that bilirubin can negatively affect auditory abilities. It disrupts the integrity of auditory pathways, resulting in auditory dysfunction and potentially causing long-term hearing impairments in infants affected by it. In conclusion, a comprehensive understanding of the complications associated with unconjugated bilirubin in neonates is essential for improving clinical management and outcomes. Understanding the cellular and molecular pathophysiology of high bilirubin may lead to a new therapeutic approach.

Bilirubin is a metabolic product of heme, and an increase in its level may be toxic to the body. It may be conjugated or unconjugated. Encephalopathy is caused by unconjugated bilirubin has the ability to pass through the blood-brain barrier, entering the central nervous system. Conjugated forms of bilirubin result in biliary obstruction and a change in urine colour due to a decrease in excretion. Excessive hemolysis can result from hereditary and autoimmune diseases, deficient RBC membranes, enzyme deficiency, and hemoglobin structural anomalies. In this review, we summarize all the possible mechanisms and complications regarding bilirubin. Cellular and molecular functions and mechanisms of bilirubin are explained, followed by several complications viz neurotoxicity, auditory dysfunction, and nephrotoxicity. The cause of bilirubin-induced neuronal cell damage is likely due to the elevated levels of unconjugated bilirubin in plasma, mitochondrial, and endoplasmic reticulum (ER) membranes. These disruptions in the membranes could lead to harmful effects such as neuronal excitotoxicity, energy failure in mitochondria, or an increased concentration of calcium within the cells. At the cellular level, bilirubin exerts its toxic effect by disturbing the normal functioning of neuronal cells. Bilirubin's presence can cause certain inflammatory responses, resulting in the activation of proinflammatory cytokines. Additionally, research has demonstrated that bilirubin can negatively affect auditory abilities. It disrupts the integrity of auditory pathways, resulting in auditory dysfunction and potentially causing long-term hearing impairments in infants affected by it. In conclusion, a comprehensive understanding of the complications associated with unconjugated bilirubin in neonates is essential for improving clinical management and outcomes. Understanding the cellular and molecular pathophysiology of high bilirubin may lead to a new therapeutic approach. [ABSTRACT FROM AUTHOR]

Background: It was aimed to investigate the clinical and demographic characteristics, risk factors and treatment methods of newborns hospitalised with a diagnosis of indirect hyperbilirubinemia. Materials and Methods: Demographic characteristics, laboratory data, and risk factors for neonatal jaundice were retrospectively examined in 615 newborn infants with jaundice admitted to the Neonatal Intensive Care Unit. Results: The infants comprised 340 (55.3%) females and 275 (44.7%) males; of which 532 (86.50%) were born at full-term, 80 (13%) premature, and 3 (0.50%) post-full-term. Birth weights; It was 3185±50 gr. The most common cause of jaundice was physiological jaundice/jaundice of unknown cause (25.7%) wheras the lowest rates were intracranial bleeding (0.3%) and congenital central nervous system anomalies (0.3%). In treatment, 406 (66.0%) of the babies received only phototherapy, and 35 (5.7%) of them also received exchange transfusion. To the remained 174 (28.3%) cases, antibiotics, sodium L-thyroxin, and/or intravenous fluid treatment were given according to the primary disease, together with phototherapy. Rebound jaundice developed in 13 (2.1%) infants, temporary hypocalcemia in 3 (0.5%), anemia in 1 (0.2%), and diarrhea in 1 (0.2%). Mortality associated with an underlying cause developed in 7 (1.1%) cases, kernicterus developed in 1 (0.2%), and 607 (98.7%) were discharged with medication. Conclusions: Hyperbilirubinemia is frequently seen in the neonatal period. Timely treatment of hyperbilirubinemia is extremely important for the prevention of morbidity and mortality. [ABSTRACT FROM AUTHOR]

Background: In low and middle-income countries, close to half of the mortality in children under the age of five years occurs in neonates. Objectives: We examined the trend, medical conditions and factors associated with newborn deaths at the Princess Marie Louise Children's Hospital (PML), Accra, from 2014 to 2017 (4 years). Methods: The study was a cross-sectional study. Data on age, sex, date of admission, date of discharge, cause of death and place of residence of these babies were obtained from the records department. This was transferred into an Access database and analyzed. Components of the Newborn Strategic Plan implemented at the hospital were described. Results: Neonatal sepsis, pneumonia and kernicterus were the major causes of death. Admissions increased and 5.4% of the neonates died, declining from 6.5% in 2014 to 4.2% in 2017 due to deliberate actions to reduce neonatal death. The highest mortality occurred in babies residing in an area more than 1 hour's drive away from the hospital. Conclusion: Implementing the Newborn Strategic Plan was associated with a drop in mortality. A preponderance of community-acquired infections was observed. Thus, locality-specific interventions targeted at known determinants and implementing the newborn strategic plan are essential for reducing neonatal mortality. [ABSTRACT FROM AUTHOR]

Bilirubin-induced neurological damage (BIND), which might progress to kernicterus, occurs as a consequence of defects in the bilirubin conjugation machinery, thus enabling albumin-unbound free bilirubin (BF) to cross the blood–brain barrier and accumulate within. A defect in the UGT1A1 enzyme-encoding gene, which is directly responsible for bilirubin conjugation, can cause Crigler–Najjar syndrome (CNS) and Gilbert's syndrome. We used human-induced pluripotent stem cell (hiPSC)-derived 3D brain organoids to model BIND in vitro and unveil the molecular basis of the detrimental effects of BF in the developing human brain. Healthy and patient-derived iPSCs were differentiated into day-20 brain organoids, and then stimulated with 200 nM BF. Analyses at 24 and 72 h post-treatment point to BF-induced neuro-inflammation in both cell lines. Transcriptome, associated KEGG, and Gene Ontology analyses unveiled the activation of distinct inflammatory pathways, such as cytokine–cytokine receptor interaction, MAPK signaling, and NFκB activation. Furthermore, the mRNA expression and secretome analysis confirmed an upregulation of pro-inflammatory cytokines such as IL-6 and IL-8 upon BF stimulation. This novel study has provided insights into how a human iPSC-derived 3D brain organoid model can serve as a prospective platform for studying the etiology of BIND kernicterus. [ABSTRACT FROM AUTHOR]

Kernicterus is a serious complication of hyperbilirubinemia, caused by neuronal injury due to excessive unconjugated bilirubin (UCB) in specific brain areas. This injury induced by this accumulation in the globus pallidus can induce severe motor dysfunction. Repetitive transcranial magnetic stimulation (rTMS) has shown neuroprotective effects in various neurological diseases. This study aimed to investigate the effects of rTMS on pallidal nerve damage and motor dysfunction in a rat model of kernicterus. Rats were divided into a sham group (n = 16), a model group (bilirubin with sham rTMS; n = 16) and an rTMS group (bilirubin with rTMS; n = 16). High-frequency rTMS (10 Hz) was applied starting from 24 h postmodeling for 7 days. The rotarod test, western blotting and immunohistochemical staining were performed to measure motor function and protein expression levels. The rTMS mitigated the negative effects of UCB on the general health of kernicterus-model rats and improved their growth and development. Furthermore, the rTMS alleviated UCB-induced motor dysfunction and increased the expression of GABAergic neuronal marker GAD67 in the globus pallidus. Notably, it also inhibited apoptosis-related protein caspase-3 activation. In conclusion, rTMS could alleviate motor dysfunction by inhibiting apoptosis and increasing globus pallidus GAD67 in kernicterus rat models, indicating that it may be a promising treatment for kernicterus. [ABSTRACT FROM AUTHOR]

Abstract Background Kernicterus in the acute phase is difficult to diagnose. It depends on a high signal on T1 at the globus pallidum and subthalamic nucleus level. Unfortunately, these areas also show a relatively high signal on T1 in neonates as an expression of early myelination. Therefore, a less myelin-dependent sequence, like SWI, may be more sensitive to detecting damage in the globus pallidum area. Case presentation A term baby developed jaundice on day three following an uncomplicated pregnancy and delivery. Total bilirubin peaked at 542 μmol/L on day four. Phototherapy was started, and an exchange transfusion was performed. ABR showed absent responses on day 10. MRI on day eight demonstrated abnormal high signal globus pallidus on T1w, isointense on T2w, without diffusion restriction, and high signal on SWI at globus pallidal and subthalamus level and phase image at globus pallidal level. These findings were consistent with the challenging diagnosis of kernicterus. On follow-up, the infant presented with sensorineural hearing loss and had a work-up for cochlear implant surgery. At 3 months of age, the follow-up MR shows normalization of the T1 and SWI signals and a high signal on T2. Conclusions SWI seems more sensitive to injury than the T1w and lacks the disadvantage of the T1w sequence, where early myelin confers a high signal.

All national and international pediatric guidelines universally prescribe meticulous bilirubin screening for neonates as a critical measure to mitigate the incidence of acute bilirubin encephalopathy (ABE) and Kernicterus. The prevailing gold standard for jaundice detection in neonates necessitates invasive blood collection, followed by subsequent biochemical testing. While the invasive procedure provides dependable bilirubin measurements and continues to be the sole gold standard diagnostic method for assessing bilirubin concentration. There exists a pressing need to innovate non-invasive screening tools that alleviate the sampling stress endured by newborns, mitigate iatrogenic anemia, and expedite the turnaround time for obtaining results. The exploration of non-invasive modalities for bilirubin measurements is gaining momentum, driven by the overarching goal of minimizing the number of pricks inflicted upon neonates, thereby rendering screening a swift, efficient, comfortable, and dependable process. This comprehensive review article delves extensively into the array of non-invasive approaches and digital solutions that have been proposed, implemented, and utilized for neonatal bilirubin screening, with a particular emphasis on their application in low-resource settings. Within this context, the review sheds light on the existing methodologies and their practical applications, with a specific focus on transcutaneous bilirubin meters. Moreover, it underscores the prevailing open challenges in this domain and outlines potential directions for future research endeavors. Notably, the review underscores the imperative need for robust educational programs targeted at both families and healthcare personnel to expedite the process of seeking timely care for neonatal jaundice. Additionally, it underscores the necessity for the development of enhanced screening and diagnostic tools that can offer greater accuracy in clinical practice.

Simple Summary: Severe neonatal hyperbilirubinemia may damage the brain, leading to motor, cognitive, and auditory abnormalities. We recently discovered that bilirubin might act by controlling the genetic developmental program of the cerebellum, a region of the brain well known to be susceptible to bilirubin-induced damage. In this paper, we expand the study of the potential impact of bilirubin in the control of postnatal brain development to brain regions better correlating with human symptoms. The maximal abnormalities of structure and cell shape (histology) were detected 9 days after birth, fully recovering later on. Differently, the analysis of the gene expression revealed transient alterations (early after birth, then recovering) in the hippocampus (memory, learning, and cognition) and inferior colliculi (auditory functions), but permanent (until adulthood) changes in the areas of the brain involved in the control of movements, information confirmed by the abnormal results on the behavioral tests. These new findings are well in agreement with the clinic and open a way for better deciphering the neurotoxic features of bilirubin neurotoxicity and potential therapeutic approaches. Recent findings indicated aberrant epigenetic control of the central nervous system (CNS) development in hyperbilirubinemic Gunn rats as an additional cause of cerebellar hypoplasia, the landmark of bilirubin neurotoxicity in rodents. Because the symptoms in severely hyperbilirubinemic human neonates suggest other regions as privileged targets of bilirubin neurotoxicity, we expanded the study of the potential impact of bilirubin on the control of postnatal brain development to regions correlating with human symptoms. Histology, transcriptomic, gene correlation, and behavioral studies were performed. The histology revealed widespread perturbation 9 days after birth, restoring in adulthood. At the genetic level, regional differences were noticed. Bilirubin affected synaptogenesis, repair, differentiation, energy, extracellular matrix development, etc., with transient alterations in the hippocampus (memory, learning, and cognition) and inferior colliculi (auditory functions) but permanent changes in the parietal cortex. Behavioral tests confirmed the presence of a permanent motor disability. The data correlate well both with the clinic description of neonatal bilirubin-induced neurotoxicity, as well as with the neurologic syndromes reported in adults that suffered neonatal hyperbilirubinemia. The results pave the way for better deciphering the neurotoxic features of bilirubin and evaluating deeply the efficacy of new therapeutic approaches against the acute and long-lasting sequels of bilirubin neurotoxicity. [ABSTRACT FROM AUTHOR]

The article focuses on the 2022 William A. Silverman Lecture by Haresh Kirpalani, who discusses the importance of evidence-based medicine in neonatology. Topics include the difference between association and causation, the limitations of physiological arguments in justifying therapies, and the verification of interventions through randomized controlled trials.

Background: Kernicterus in the acute phase is difficult to diagnose. It depends on a high signal on T1 at the globus pallidum and subthalamic nucleus level. Unfortunately, these areas also show a relatively high signal on T1 in neonates as an expression of early myelination. Therefore, a less myelin-dependent sequence, like SWI, may be more sensitive to detecting damage in the globus pallidum area. Case presentation: A term baby developed jaundice on day three following an uncomplicated pregnancy and delivery. Total bilirubin peaked at 542 μmol/L on day four. Phototherapy was started, and an exchange transfusion was performed. ABR showed absent responses on day 10. MRI on day eight demonstrated abnormal high signal globus pallidus on T1w, isointense on T2w, without diffusion restriction, and high signal on SWI at globus pallidal and subthalamus level and phase image at globus pallidal level. These findings were consistent with the challenging diagnosis of kernicterus. On follow-up, the infant presented with sensorineural hearing loss and had a work-up for cochlear implant surgery. At 3 months of age, the follow-up MR shows normalization of the T1 and SWI signals and a high signal on T2. Conclusions: SWI seems more sensitive to injury than the T1w and lacks the disadvantage of the T1w sequence, where early myelin confers a high signal. [ABSTRACT FROM AUTHOR]

Our objective was to assess the relationship between hyperbilirubinemia with and without kernicterus and metabolic profile at newborn screening. Included were 1,693,658 infants divided into a training or testing subset in a ratio of 3:1. Forty-two metabolites were analyzed using logistic regression (odds ratios (ORs), area under the receiver operating characteristic curve (AUC), 95% confidence intervals (CIs)). Several metabolite patterns remained consistent across gestational age groups for hyperbilirubinemia without kernicterus. Thyroid stimulating hormone (TSH) and C-18:2 were decreased, whereas tyrosine and C-3 were increased in infants across groupings. Increased C-3 was also observed for kernicterus (OR: 3.17; 95% CI: 1.18-8.53). Thirty-one metabolites were associated with hyperbilirubinemia without kernicterus in the training set. Phenylalanine (OR: 1.91; 95% CI: 1.85-1.97), ornithine (OR: 0.76; 95% 0.74-0.77), and isoleucine + leucine (OR: 0.63; 95% CI: 0.61-0.65) were the most strongly associated. This study showed that newborn metabolic function is associated with hyperbilirubinemia with and without kernicterus.

Background: Hyperbilirubinemia is one of the most common diagnosis in newborn nurseries in United States. Universal pre-discharge bilirubin screening decreased the incidence of extreme hyperbilirubinemia and risk of kernicterus. Objectives: We sought to assess temporal population trends of hyperbilirubinemia, kernicterus and usage of phototherapy, intravenous immunoglobulin (IVIG), and exchange transfusion. Design/methods: Data from Healthcare Cost and Utilization Project (HCUP)-the Kids' Inpatient Database (KID) obtained for years 1997-2012. All neonatal discharges with ICD-9 codes for neonatal jaundice (774.2, 774.6), kernicterus (773.4, 774.7) and procedure codes for phototherapy (99.83), IVIG infusion (99.14), exchange transfusion (99.01) were extracted. We compared the trends of diagnosis of hyperbilirubinemia, kernicterus, use of phototherapy, IVIG, and exchange transfusion. Results: During the study period, the proportion of infants diagnosed with hyperbilirubinemia increased by 65% (9.4% vs. 15.5%; p<.001) in term infants and 34.5% (33.5% vs. 45%; p<.001) in preterm infants, respectively. Rate of kernicterus discharges significantly reduced from 7 to 1.9 per 100,000 newborns. Overall, the number of exchange transfusions has decreased by 67% during study period while phototherapy and IVIG use increased by 83% and 170%, respectively. Conclusions: In last two decades, there was a significant decrease in neonatal discharges with a history of exchange transfusion or with a diagnosis of kernicterus. However, there was a significant increase in number of neonates discharged home with a history of phototherapy during birth hospitalization and decreased number of exchange transfusions were observed during the study period. Incremental implementation of universal predischarge bilirubin screening and treatments based on 2004 AAP recommended risk-based strategies might have contributed to timely interventions in infants with significant hyperbilirubinemia. [ABSTRACT FROM AUTHOR]

Background: Neonatal jaundice occurs in more than 80% of newborn infants. Although mild jaundice is physiologic and possibly neuroprotective, severe hyperbilirubinemia can lead to neurologic dysfunction and death. Hyperbilirubinemia is due to an imbalance between bilirubin production and the developing excretory capacity in the first days of life. Management utilizes total serum bilirubin (TSB) levels, although recent advances suggest a role for unbound bilirubin. Goals: The goal of this review is to examine bilirubin biology, toxicology, and clinical effects, discuss preventive and therapeutic measures, describe neurodevelopmental consequences, and propose that, with the advent of new technology, unbound bilirubin is the optimal measurement for the management. Methods: Comprehensive review on neonatal hyperbilirubinemia. Results: Neonatal hyperbilirubinemia can be prevented by tin mesoporphyrin to limit heme oxygenase activity, a key enzyme in bilirubin production, or restricting bilirubin’s absorption from the gastrointestinal tract. Treatment modalities include removing bilirubin from the body by exchange transfusion, binding to immunoglobulin, or converting it to a water-soluble isomer with phototherapy. While these approaches have evolved during the past decades, the diagnosis, intervention indications, and prognosis have consistently relied on TSB concentration despite its poor ability to predict an outcome. Conclusions: Total serum bilirubin is inadequate to optimize care of the term and preterm infant with hyperbilirubinemia. A rapid, accurate, and more effective indicator of bilirubin neurotoxicity is needed to manage jaundiced infants and for the universal screening of newborn infants. Future measurements of free bilirubin unattached to albumin will improve the management of neonatal hyperbilirubinemia. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Crigler-Najjar syndrome is a rare genetic disorder that causes severe unconjugated hyperbilirubinaemia. The syndrome is caused by a mutation in the UGT1A1 gene, which results in a deficiency or complete lack of the UGT1A1 enzyme, which is responsible for the conjugation of bilirubin. If the disease remains unrecognised or untreated it can cause severe neu-rological consequences. on a patient and his family. The key to a good prognosis is aggressive treatment of unconjugated hyperbilirubinaemia with phototherapy as soon as possible. The life expectancy and the quality of life of people with Crigler-Najjar syndrome have improved greatly with the use of phototherapy and other therapeutic methods. At the moment, the only cure is liver transplantation with some potential treatments still in the phase of clinical trials.

Bilirubin-induced neurological damage (BIND), which might progress to kernicterus, occurs as a consequence of defects in the bilirubin conjugation machinery, thus enabling albumin-unbound free bilirubin (BF) to cross the blood–brain barrier and accumulate within. A defect in the UGT1A1 enzyme-encoding gene, which is directly responsible for bilirubin conjugation, can cause Crigler–Najjar syndrome (CNS) and Gilbert’s syndrome. We used human-induced pluripotent stem cell (hiPSC)-derived 3D brain organoids to model BIND in vitro and unveil the molecular basis of the detrimental effects of BF in the developing human brain. Healthy and patient-derived iPSCs were differentiated into day-20 brain organoids, and then stimulated with 200 nM BF. Analyses at 24 and 72 h post-treatment point to BF-induced neuro-inflammation in both cell lines. Transcriptome, associated KEGG, and Gene Ontology analyses unveiled the activation of distinct inflammatory pathways, such as cytokine–cytokine receptor interaction, MAPK signaling, and NFκB activation. Furthermore, the mRNA expression and secretome analysis confirmed an upregulation of pro-inflammatory cytokines such as IL-6 and IL-8 upon BF stimulation. This novel study has provided insights into how a human iPSC-derived 3D brain organoid model can serve as a prospective platform for studying the etiology of BIND kernicterus.

Background:Neonatal hyperbilirubinemia is a common problem in neonates.Phototherapy is an efficient way to decrease the accumulation of bilirubin, although it involves hospitalization, and can force the baby to stop eating due to the breast separation. In certain cases of infant jaundice, the hepatic circulation of bilirubin plays a major role Objectives: The purpose of the study was todetermine the value of oral agar ingestion combined with phototherapy in management of neonatal unconjugated hyperbilirubinemia and to compare it with the use of phototherapy alone in the management. Patients and methods: This was a randomized controlled study conducted at Neonatal intensive care units in Qena university hospital and Qena general hospital. They were divided into: Case group (neonates received oral agar with phototherapy).Control group (neonates received phototherapy alone). The duration of this study was 6 months. Results: The study included 517 neonates,314 neonates (60.74%) treated withphototherapy alone and 203 neonates (39.26%) treated withphototherapy combined with agar .There was a significant decrease in total serum bilirubin (TSB) in both subgroups, but the decrease was more significant in term male babies andin group that received agar with phototherapy than the group received phototherapy alone. Conclusion: Our results show that the administration of oral agar in full-term neonates was safe to decrease total serum bilirubin (TSB) concentrations and to shorten the length of phototherapy in hyperbilirubinemic neonates. As a supplementary treatment for neonates with hyperbilirubinemia, our results indicated that agar may benefit in minimizing the length of hospitalization.

Neonatal jaundice (NJ) is common in newborn infants. Severe NJ (SNJ) has potentially negative neurological sequelae that are largely preventable in high resource settings if timely diagnosis and treatment are provided. Advancements in NJ care in low- and middle-income countries (LMIC) have been made over recent years, especially with respect to an emphasis on parental education about the disease and technological advancements for improved diagnosis and treatment. Challenges remain, however, due to lack of routine screening for SNJ risk factors, fragmented medical infrastructure, and lack of culturally appropriate and regionally specific treatment guidelines. This article highlights both encouraging advancements in NJ care as well as remaining gaps. Opportunities are identified for future work in eliminating the gaps in NJ care and preventing death and disability related to SNJ around the globe.

To assess interlaboratory variability of total serum bilirubin (TSB) results in newborns. Initiated following a clinical incident in which a neonate was transferred to a tertiary hospital for treatment of severe hyperbilirubinemia but on arrival was reclassified into a lower risk category due to a 20% difference in TSB between laboratories. Fresh residual plasma samples from hospital-born infants were pooled to obtain 11 samples across a range of total bilirubin concentrations. Aliquots were light-protected and measured on 7 commercial platforms at 4 accredited medical laboratories. Data from The Royal College of Pathologists of Australasia Quality Assurance Programs' (RCPAQAP) Neonatal Bilirubin program was analysed. Twenty-four to 30% difference in results for individual samples, largely due to calibration differences between assays. When interpreted according to guidelines, results from different platforms would have led to different clinical interventions in some cases. RCPAQAP results showed significant within-method bias but were not shown to be commutable with patient samples. There are clinically significant method-dependent differences in TSB results from neonatal samples, consistent with our clinical incident. The differences are largely due to lack of standardisation of calibrator values. This has implications for healthcare resource use and possibly for the neurodevelopment of infants. Intervention is needed at a number of levels, including clinical reporting of incidents arising from discordant results, commitment by manufacturers to ensure metrological traceability of methods with sufficiently low uncertainty in the final measurements, and availability of commutable quality assurance material to monitor assay performance, especially at the clinical decision points for neonatal jaundice. [ABSTRACT FROM AUTHOR]

Gilbert’s syndrome is a genetic disorder characterised by non-hemolytic unconjugated hyperbilirubinemia. It is caused by mutations in the UGT1A1 gene which codes for the enzyme uridine diphosphate glucoronosyl transferase-1, which conjugates bilirubin for excretion. Affected individuals are usually asymptomatic apart from a mild jaundice and investigations reveal a mild isolated indirect hyperbilirubinemia. This may be exacerbated in the face of environmental and physical stressors. It is very similar in presentation to Criggler-Najjar syndrome (CNS) type 2. There is a small risk of kernicterus in patients with CNS type 2 needing daily phenobarbitone therapy. This risk is miniscule in Gilbert’s syndrome. Genetic testing for polymorphisms of the UGT1A1 gene is the diagnostic clincher for Gilbert’s syndrome, but it can also be picked up by evaluating the response to phenobarbitone and fasting, particularly in resource poor settings. Due to limited availability, case reports documenting the genetic mutational analysis are sparse. We reported one such rare case with an unusually high indirect hyperbilirubinemia in Gilbert’s syndrome confirmed by both phenobarbitone response and genetic analysis. [ABSTRACT FROM AUTHOR]

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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 ≥35weeks' 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. [ABSTRACT FROM AUTHOR]

The article updates and replaces the 2004 American Academy of Pediatrics (AAP) clinical practice guideline for the management and prevention of hyperbilirubinemia in the newborn infant 35 or more weeks of gestation. Topics discussed include guideline development process, information on previous guidelines, and risk factors for developing significant hyperbilirubinemia.

Bilirubin-induced neurological damage (BIND) has been a subject of studies for decades, yet the molecular mechanisms at the core of this damage remain largely unknown. Throughout the years, many in vivo chronic bilirubin encephalopathy models, such as the Gunn rat and transgenic mice, have further elucidated the molecular basis of bilirubin neurotoxicity as well as the correlations between high levels of unconjugated bilirubin (UCB) and brain damage. Regardless of being invaluable, these models cannot accurately recapitulate the human brain and liver system; therefore, establishing a physiologically recapitulating in vitro model has become a prerequisite to unveil the breadth of complexities that accompany the detrimental effects of UCB on the liver and developing human brain. Stem-cell-derived 3D brain organoid models offer a promising platform as they bear more resemblance to the human brain system compared to existing models. This review provides an explicit picture of the current state of the art, advancements, and challenges faced by the various models as well as the possibilities of using stem-cell-derived 3D organoids as an efficient tool to be included in research, drug screening, and therapeutic strategies for future clinical applications. [ABSTRACT FROM AUTHOR]

Context: Debate exists regarding predictive value of brain MRI for long-term neurodevelopmental outcome (NDO) in infants with severe unconjugated hyperbilirubinemia (above exchange transfusion levels)., Objective: To investigate whether MRI findings among (pre-)term infants with severe unconjugated hyperbilirubinemia can predict NDO at ≥ 12 months and determine optimal timing for MRI., Data Sources: PubMed and Embase. Last update: June 14, 2024., Study Selection: Studies in which (pre-)term infants with severe unconjugated hyperbilirubinemia who underwent an MRI before 24 months and had a reported NDO at ≥ 12 months were included., Data Extraction: Patient characteristics, MRI and NDO details were extracted., Results: The search yielded 732 studies, of which 22 were included. Individual patient information was obtained for 120 infants (MRI-timing: early (≤6 weeks) n = 75, late (>6 weeks) n = 19, unknown n = 26). Positive predictive value (PPV) of abnormal MRI in the total group for impaired NDO was high (77.5 %). The PPV of late compared to early MRI was much higher, 92.3 % versus 71.7 %. Negative predictive value of normal MRI for normal NDO in the total group was low (29.0 %) and again higher in late compared to early MRI, 50.0 % versus 27.3 %., Limitations: Quantitative synthesis of results was impossible due to large heterogeneity in study designs. Furthermore, selection bias towards patients with impaired outcome might have influenced our results., Conclusions: Brain MRI can serve as prognostic tool for NDO in infants with severe unconjugated hyperbilirubinemia, both in early and late stages, but each timing has inherent constraints. Further prospective studies are necessary., Competing Interests: Declaration of competing interest None., (Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Kernicterus is a serious complication of hyperbilirubinemia, caused by neuronal injury due to excessive unconjugated bilirubin (UCB) in specific brain areas. This injury induced by this accumulation in the globus pallidus can induce severe motor dysfunction. Repetitive transcranial magnetic stimulation (rTMS) has shown neuroprotective effects in various neurological diseases. This study aimed to investigate the effects of rTMS on pallidal nerve damage and motor dysfunction in a rat model of kernicterus. Rats were divided into a sham group (n = 16), a model group (bilirubin with sham rTMS; n = 16) and an rTMS group (bilirubin with rTMS; n = 16). High-frequency rTMS (10 Hz) was applied starting from 24 h postmodeling for 7 days. The rotarod test, western blotting and immunohistochemical staining were performed to measure motor function and protein expression levels. The rTMS mitigated the negative effects of UCB on the general health of kernicterus-model rats and improved their growth and development. Furthermore, the rTMS alleviated UCB-induced motor dysfunction and increased the expression of GABAergic neuronal marker GAD67 in the globus pallidus. Notably, it also inhibited apoptosis-related protein caspase-3 activation. In conclusion, rTMS could alleviate motor dysfunction by inhibiting apoptosis and increasing globus pallidus GAD67 in kernicterus rat models, indicating that it may be a promising treatment for kernicterus.

Recent findings indicated aberrant epigenetic control of the central nervous system (CNS) development in hyperbilirubinemic Gunn rats as an additional cause of cerebellar hypoplasia, the landmark of bilirubin neurotoxicity in rodents. Because the symptoms in severely hyperbilirubinemic human neonates suggest other regions as privileged targets of bilirubin neurotoxicity, we expanded the study of the potential impact of bilirubin on the control of postnatal brain development to regions correlating with human symptoms. Histology, transcriptomic, gene correlation, and behavioral studies were performed. The histology revealed widespread perturbation 9 days after birth, restoring in adulthood. At the genetic level, regional differences were noticed. Bilirubin affected synaptogenesis, repair, differentiation, energy, extracellular matrix development, etc., with transient alterations in the hippocampus (memory, learning, and cognition) and inferior colliculi (auditory functions) but permanent changes in the parietal cortex. Behavioral tests confirmed the presence of a permanent motor disability. The data correlate well both with the clinic description of neonatal bilirubin-induced neurotoxicity, as well as with the neurologic syndromes reported in adults that suffered neonatal hyperbilirubinemia. The results pave the way for better deciphering the neurotoxic features of bilirubin and evaluating deeply the efficacy of new therapeutic approaches against the acute and long-lasting sequels of bilirubin neurotoxicity.

Introduction: Glucose 6-phosphate dehydrogenase (G6PD) deficiency increases the risk of severe neonatal hyperbilirubinemia. This study evaluates the risk factors predicting the need for phototherapy in G6PD-deficient neonates after 72 h of age and assesses the safety of early discharge. Methods: A retrospective cohort study of 681 full-term G6PD-deficient infants with a birth weight ≥2,500 g over 4 years was conducted. We compared the baseline characteristics, bilirubin level on day 4 (after 72 h of life), day of peak bilirubin, G6PD levels, and concomitant ABO incompatibility between the group that required phototherapy (Group A) and those who did not (Group B). Results: 396 infants (58%), predominantly males, required phototherapy in the first week of life. The infants who required phototherapy had a lower median gestational age (38.3 vs. 38.7 weeks, p < 0.01) and had lower G6PD levels (2.3 ± 2.5 vs. 3 ± 3.4 IU, p < 0.05) compared to the controls. The mean day-four total serum bilirubin (TSB) levels were higher (213 ± 32 vs. 151 ± 37 µmol/L, p < 0.01), with bilirubin level peaking earlier (3 vs. 4 days of life, p < 0.01) in group A. Regression analysis identified TSB levels on day 4, Chinese race, lower gestation, and concomitant ABO incompatibility as the significant predictors for the need for phototherapy in the study population. In particular, coexisting ABO blood group incompatibility increased the risk of jaundice requiring phototherapy (OR 4.27, 95% CI: 1.98–121, p < 0.01). Day four TSB values above 180 µmol/L predicted the need for phototherapy with 86% sensitivity and 80% specificity. The findings were similar across both male and female infants with G6PD deficiency. Conclusion: G6PD-deficient infants with day four TSB levels of >180 µmol/L (10.5 mg/dL) and associated ABO blood group incompatibility have a higher risk of requiring phototherapy in the first week of life and should be closely monitored. [ABSTRACT FROM AUTHOR]

Objective. To explore the influencing factors of severe hyperbilirubinemia in neonates complicated with acute bilirubin encephalopathy (ABE) and then build relevant prediction models and evaluate the prediction performance of the models. Methods. The data of 120 neonates with severe hyperbilirubinemia were collected by retrospective analysis. Univariate and multivariate analysis methods were used to analyze the data of 120 children. R software was used to visualize the results of multivariate analysis, and a nomogram model was obtained. The receiver operating characteristic curve (ROC), calibration curve, and decision-making curve (DC) were used to evaluate the discrimination, accuracy, and clinical net profit rate of the model. Results. Multivariate analysis showed that nonfull breastfeeding, high-risk symptoms, and pregnancy complications were independent risk factors for ABE in neonates with severe hyperbilirubinemia. At the same time, the risk of ABE in neonates with severe hyperbilirubinemia increased with the increase of B/A and Hb levels. The ROC curve showed that the area under the curve for the model was 0.908 (95% CI: 0.839–0.960). The calibration curve shows that the actual prediction curve of the model is in good agreement with the corrected prediction curve. Using the cutoff value of the ROC curve as the diagnostic criterion, the threshold probability of the model was calculated to be 38%. The decision curve shows that when 38% is used as the basis for judging whether to take measures to intervene, the profit rate is 61%. Conclusion. The occurrence of ABE in neonates with severe hyperbilirubinemia is affected by many factors, and there is a certain degree of interaction between these factors. Combining multiple factors to construct a risk nomogram model can provide a reference for early clinical detection of high-risk neonates. [ABSTRACT FROM AUTHOR]

Severe neonatal hyperbilirubinemia (SNH) and the onset of bilirubin encephalopathy and kernicterus result in part from delayed expression of UDP-glucuronosyltransferase 1A1 (UGT1A1) and the inability to metabolize bilirubin. Although there is a good understanding of the early events after birth that lead to the rapid increase in serum bilirubin, the events that control delayed expression of UGT1A1 during development remain a mystery. Humanized UGT1 (hUGT1) mice develop SNH spontaneously, which is linked to repression of both liver and intestinal UGT1A1. In this study, we report that deletion of intestinal nuclear receptor corepressor 1 (NCoR1) completely diminishes hyperbilirubinemia in hUGT1 neonates because of intestinal UGT1A1 gene derepression. Transcriptomic studies and immunohistochemistry analysis demonstrate that NCoR1 plays a major role in repressing developmental maturation of the intestines. Derepression is marked by accelerated metabolic and oxidative phosphorylation, drug metabolism, fatty acid metabolism, and intestinal maturation, events that are controlled predominantly by H3K27 acetylation. The control of NCoR1 function and derepression is linked to IKKβ function, as validated in hUGT1 mice with targeted deletion of intestinal IKKβ. Physiological events during neonatal development that target activation of an IKKβ/NCoR1 loop in intestinal epithelial cells lead to derepression of genes involved in intestinal maturation and bilirubin detoxification. These findings provide a mechanism of NCoR1 in intestinal homeostasis during development and provide a key link to those events that control developmental repression of UGT1A1 and hyperbilirubinemia.