Innovative approaches to neonatal jaundice diagnosis and management in low-resourced settings.

Persistent challenges in addressing severe neonatal hyperbilirubinaemia in resource-constrained settings have led to ongoing and often unacceptable rates of morbidity, disability and mortality. These challenges stem from limitations such as inadequate, inefficient or financially inaccessible diagnostic and therapeutic options. However, over the past decade, noteworthy innovations have emerged to address some of these hurdles, and these innovations are increasingly poised for broader implementation. This review provides a concise summary of these novel, economically viable diagnostic solutions, encompassing point-of-care assays and smartphone applications, as well as treatment modalities, notably more effective phototherapy and filtered sunlight. These advancements hold promise and have the potential to meaningfully reduce the burden of neonatal hyperbilirubinaemia, signifying a promising shift in the landscape of neonatal healthcare.

Delivery of a post-natal neonatal jaundice education intervention improves knowledge among mothers at Jinja Regional Referral Hospital in Uganda.

BACKGROUND: Neonatal jaundice (NNJ) is a major contributor to childhood morbidity and mortality. As many infants are discharged by 24 hours of age, mothers are key in detecting severe forms of jaundice. Mothers with limited knowledge of NNJ have a hard time identifying these infants who could go on to have the worst outcomes. This study aimed to determine the effect of a jaundice education package delivered to mothers prior to hospital discharge on maternal knowledge after discharge. METHODS: This was a before and after interventional study involving an education package delivered through a video message and informational voucher. At 10-14 days after discharge, participants were followed up via telephone to assess their post-intervention knowledge. A paired t-test was used to determine the effectiveness of the intervention on knowledge improvement. Linear regression was used to determine predictors of baseline knowledge and of change in knowledge score. RESULTS: Of the 250 mothers recruited, 188 were fit for analysis. The mean knowledge score was 10.02 before and 14.61 after the intervention, a significant difference (p<0.001). Factors determining higher baseline knowledge included attendance of 4 or more antenatal visits (p < 0.001), having heard about NNJ previously (p < 0.001), having experienced an antepartum illness (p = 0.019) and higher maternal age (p = 0.015). Participants with poor baseline knowledge (ß = 7.523) and moderate baseline knowledge (ß = 3.114) had much more to gain from the intervention relative to those with high baseline knowledge (p < 0.001). CONCLUSION: Maternal knowledge of jaundice can be increased using a simple educational intervention, especially in settings where the burden of detection often falls on the mother. Further study is needed to determine the impact of this intervention on care seeking and infant outcomes.

Application of machine learning algorithms for accurate determination of bilirubin level on in vitro engineered tissue phantom images.

Neonatal Jaundice is a common occurrence in neonates. High excess bilirubin would lead to hyperbilirubinemia, leading to irreversible adverse damage such as kernicterus. Therefore, it is necessary and important to monitor neonates' bilirubin levels in real-time for immediate intervention. However, current screening protocols have their inherent limitations, necessitating more convenient measurements. In this proof-of-concept study, we evaluated the feasibility of using machine learning for the screening of hyperbilirubinemia in neonates from smartphone-acquired photographs. Different machine learning models were compared and evaluated to gain a better understanding of feature selection and model performance in bilirubin determination. An in vitro study was conducted with a bilirubin-containing tissue phantom to identify potential biological and environmental confounding factors. The findings of this study present a systematic characterization of the confounding effect of various factors through separate parametric tests. These tests uncover potential techniques in image pre-processing, highlighting important biological features (light scattering property and skin thickness) and external features (ISO, lighting conditions and white balance), which together contribute to robust model approaches for accurately determining bilirubin concentrations. By obtaining an accuracy of 0.848 in classification and 0.812 in regression, these findings indicate strong potential in aiding in the design of clinical studies using patient-derived images.

Bilirubin Measurement and Phototherapy Use After the AAP 2022 Newborn Hyperbilirubinemia Guideline.

BACKGROUND AND OBJECTIVES: Guidelines for the management of neonatal hyperbilirubinemia have helped to reduce rates of significant hyperbilirubinemia. However, recent evidence suggesting overtreatment and potential harms of phototherapy have informed the American Academy of Pediatrics clinical practice guideline revision and the accompanying increase in phototherapy thresholds. These changes are predicted to safely reduce overuse; however, to date, the exact effect of these guidelines has not been established. METHODS: We conducted a retrospective study of newborns born at ≥35 weeks' gestation across a network of 8 hospitals between January 2022 and June 2023. Outcomes included rates of phototherapy and total serum bilirubin (TSB) measurements before and after guideline publication, as well as clinical outcomes, including length of stay, readmissions, and duration of phototherapy. RESULTS: In our cohort of >22 000 newborns, we observed a 47% decrease in phototherapy utilization, from 3.9% to 2.1% (P < .001). TSB measurements were reduced by 23%, from 712 to 551 measurements per 1000 newborns (P < .001), without an increase in outpatient TSB measurements. We did not observe an increase in readmissions receiving phototherapy, and length of stay increased by only 1 hour (P < .001). CONCLUSIONS: Our study reveals that the publication of the updated American Academy of Pediatrics 2022 hyperbilirubinemia guidelines has likely yielded a significant reduction in phototherapy use and serum bilirubin measurement. Dedicated quality improvement initiatives may help determine which implementation strategies are most effective. Further population-level studies are needed to confirm safety with ongoing guideline uptake.

Effectiveness of phototherapy with and without probiotics for the treatment of indirect hyperbilirubinaemia in preterm neonates: a randomised controlled trial.

INTRODUCTION: Raised serum bilirubin levels can cause kernicterus, and premature infants are at increased risk owing to metabolic immaturity. The standard treatment for neonatal jaundice is phototherapy, but probiotics alone can reduce the duration of phototherapy and hospitalisation. OBJECTIVES: To determine the effectiveness of phototherapy with and without probiotics for the treatment of indirect hyperbilirubinaemia in preterm neonates. PATIENTS AND METHODS: The open-labelled randomised controlled trial was conducted from January 2022 to January 2023 in the neonatal unit of the University of Lahore Teaching Hospital, Pakistan. A total of 76 preterm neonates who fulfilled the selection criteria were included and divided into two groups. Both groups received standard phototherapy. In Group B, a probiotic (Saccharomyces boulardii) 125 mg, twice daily, orally (in 5 cc of whichever milk the infant was receiving) was given until discharge from hospital. The primary outcome measurements were the duration of phototherapy and the length of hospitalisation. RESULTS: The mean (SD) duration of phototherapy was 36.55 (14.25) hours in Group A and 24.61 (9.25) hours in Group B (p <0.05). The mean (SD) duration of hospital stay was 47.36 (16.51) hours in Group A and 33.13 (8.93) hours in Group B (p <0.05). CONCLUSION: Oral probiotics (Saccharomyces boulardii) have a significant effect on the duration of phototherapy for neonatal hyperbilirubinaemia, and they decrease the chances of nosocomial infection. Exploration of clinical outcomes by investigating faecal flora and undertaking large randomised controlled trials of various probiotics are needed. ABBREVIATIONS: ABE: acute bilirubin encephalopathy; CNS: central nervous system; GA: gestational age; IVIG: intravenous immunoglobulin; KSD: kernicterus; NNU: neonatal unit; RCT: randomised controlled trial; S. boulardii: Saccharomyces boulardii.

Minocycline attenuates the bilirubin-induced developmental neurotoxicity through the regulation of innate immunity and oxidative stress in zebrafish embryos.

When liver or intestinal function is impaired, bilirubin accumulates in the body and leads to neonatal jaundice. However, the potential negative effects caused by excessive accumulation of bilirubin such as developmental immunotoxicity and neurotoxicity remain unclear. We used a zebrafish model to establish bilirubin-induced jaundice symptoms and evaluated the toxic effects of bilirubin in aquatic organisms. Firstly, our results suggested that bilirubin exposure markedly decreased the survival rate, induced the developmental toxicity and increased the yellow pigment deposited in the zebrafish tail. Meanwhile, the number of macrophages and neutrophils was substantially reduced in a concentration-dependent manner. Besides, the antioxidant enzyme activities were greatly elevated while the inflammatory genes were significantly decreased after bilirubin exposure. Secondly, transcriptome analysis identified 708 genes were differentially expressed after bilirubin exposure, which animal organ morphogenesis, chemical synaptic transmission, and MAPK / mTOR signaling pathways were significantly enriched. Thirdly, bilirubin exposure leads to a significant decrease in the motility of zebrafish, including a dose-dependent decrease in the travelled distance, movement time, and average velocity. Moreover, the innate immune genes and apoptosis-related genes such as TLR4, NF-κB p65, STAT3 and p53 were elevated at a concentration of 10 µg/mL of bilirubin. Finally, our results further revealed that the anti-inflammatory and neuroprotective minocycline could partially rescue the bilirubin-induced neurobehavioral disorders in zebrafish embryos. In conclusion, our study explored the bilirubin-induced immunotoxicity and neurotoxicity in aquatic organisms, which will provide a theoretical basis for the treatment of neonatal jaundice in clinical practice.

Factors associated with neonatal jaundice among neonates admitted at referral hospitals in northeast Ethiopia: a facility-based unmatched case-control study.

BACKGROUND: Neonatal jaundice is a significant contributor to illness and death in newborns, leading to frequent admissions to neonatal intensive care units. To better understand this issue, a study was conducted to identify the factors contributing to neonatal jaundice among newborns admitted to Dessie and Woldia comprehensive specialized hospitals in northeast Ethiopia. METHODS: The study took place from April 1 to May 30, 2022, using unmatched case-control design. A total of 320 neonates paired with their mothers were involved, including 64 cases and 256 controls. Data were collected through a structured interviewer-administered questionnaire and a review of medical records. The collected data were analyzed using SPSS Version 23, and a multivariate logistic regression model was employed to understand the relationship between independent factors and the occurrence of neonatal jaundice. Statistical significance was determined at a threshold of P value less than 0.05. RESULTS: The study findings revealed that maternal age over 35 years, residing in urban areas [adjusted odds ratio (AOR) = 2.4, 95% confidence interval (CI): 1.23, 4.82], male gender (AOR = 4.3, 95% CI: 1.90, 9.74), prematurity (AOR = 3.9, 95% CI: 1.88, 8.09), and ABO incompatibility (AOR = 2.6, 95% CI: 1.16, 5.96) were significant determinants of neonatal jaundice. Conversely, the study indicated that cesarean birth was associated with a 76% lower likelihood of infant jaundice compared to vaginal delivery (AOR = 0.24, 95% CI: 0.08, 0.72). CONCLUSION: To prevent, diagnose, and treat neonatal jaundice effectively, efforts should primarily focus on managing ABO incompatibility and early detection of prematurity. Additionally, special attention should be given to neonates born through vaginal delivery, those with mothers over 35 years old, and those residing in urban areas, as they are at higher risk of developing newborn jaundice. Close monitoring of high-risk mother-infant pairs during the antenatal and postnatal periods, along with early intervention, is crucial for reducing the severity of neonatal jaundice in this study setting.

Validity of BiliDx as a point-of-care bilirubin measurement device to diagnose and monitor neonatal jaundice at Muhimbili National Hospital, an observational study.

BACKGROUND: Neonatal jaundice is a condition caused by elevated levels of bilirubin in the bloodstream. Laboratory determination of serum bilirubin concentration by total serum bilirubin (TSB) test is still considered as gold standard for clinical guidance and practice. In developed countries, diagnosis of neonatal jaundice is shifting towards point-of-care medical devices. BiliDx is a device developed to allow a fast, blood-based determination of bilirubin levels at the point of care. This study aimed to determine the accuracy of the BiliDx device relative to a standard laboratory total serum bilirubin to diagnose and monitor jaundice among neonates admitted at Muhimbili National Hospital (MNH). MATERIAL AND METHODOLOGY: This was a prospective hospital-based observational study conducted at the Neonatal Ward - MNH, Dar-es-Salaam, Tanzania from November 2022 to January 2023. A total of 180 neonates admitted at the neonatal ward with jaundice and whose parents consented were enrolled in the study. Blood samples were collected; 2 ml of venous blood into the vacutainer bottle for standard laboratory measurement of total serum bilirubin (TSB) and 25µL blood collected into a transfer pipette tube and applied to BiliDx. STATA version 15.1 was used for data analysis. RESULTS: Out of 180 neonates, 39.4% (71/180) had birth weight between 1500 - 2499.9 g, approximately 2/3rd (120/180) were preterm, 92/180 (51.1%) were males and 100/180 (55.6%) were undergoing phototherapy treatment the moment sample taken. The mean bilirubin concentration was 92 mmol/l for BiliDx and 118 mmol/l for standard laboratory TSB. The minimum and maximum values obtained with BiliDx were, 3.4 and 427.5 mmol/l respectively, compared with 10.7 and 382.1 mmol/l using standard laboratory TSB. A linear relationship and correlation coefficient of 0.8408 (p = 0.000) between BiliDx and standard laboratory TSB was found. The regression analysis showed the presence of constant error [coefficient of BiliDx/slope = 0.91, 95% CI (0.82-0.99), p = 0.000] and random error exclusively [coefficient of constant/y-intercept = 48.52, 95%CI (37.70-59.34), p = 0.000]. The Bland-Altman plot showed an acceptable mean difference of 39.1mmol/l, limits of agreement of -48.3mmol/l to 126.4mmol/l, and 179 points (179/180 = 99.4%) lying inside the limits of agreement. CONCLUSION: The results support the use of BiliDx for rapid and accurate testing of elevated levels of bilirubin in the bloodstream among neonates since 99.4% of the differences between BiliDx and standard laboratory TSB lie between the lines of agreement.

Experiences with neonatal jaundice management in hospitals and the community: interviews with Australian health professionals.

INTRODUCTION: Worldwide, neonatal jaundice accounts for considerable morbidity and mortality. Although severe adverse outcomes, such as hyperbilirubinaemia and kernicterus, are uncommon in high-income countries, these outcomes do occur, have enormous lifelong personal, health and social costs, and may be preventable. Evidence-based practice commonly relies on clinical guidelines; however, their implementation can be difficult. Implementation of neonatal jaundice care has been adversely affected by issues with professional boundaries, competing professional priorities and poor understanding of neonatal jaundice. This paper focuses on the perceptions and experiences of Australian health professionals involved in the management of neonatal jaundice. METHODS: Using a qualitative descriptive approach, semistructured interviews were undertaken to gain understanding of the experiences of health professionals in Australia across the scope of care for jaundiced newborns through an interpretivist approach and to identify possible gaps in the delivery of evidence-based care. Health professionals from a range of disciplines and care settings were recruited by purposive maximum variation sampling. Interviews were conducted face-to-face or by telephone with detailed notes taken and a field journal maintained. Interview scripts were verified by participants and imported into NVivo software. Data were analysed for major themes according to type and contexts of practice. RESULTS: Forty-one health professionals from six broad discipline areas were interviewed. Two major themes and explanatory subthemes were found. The first theme, falling through the gaps, highlighted gaps in evidence-based care, as described by four explanatory subthemes: professional boundaries, blindness to possibility of adverse outcomes, competing professional development priorities and unintended consequences.The second major theme, we know what should happen-but how?, described participant perceptions that it was known what was required to improve care but how to achieve such changes was unclear. The two subthemes are: improvements in education and training, and standardised policies and protocols. CONCLUSIONS: Multiple barriers to the provision of evidence-based care related to neonatal jaundice management are experienced by health professionals in Australia. Clinical guidelines are not sufficient to support health professionals deliver evidence-based care in the complex contexts in which they work. Implementation strategies for evidence-based practice need to take account of the experiences of health professionals and the challenges they face. Such strategies need to focus on improving collaboration between different disciplines for the well-being of those needing care. In the case of neonatal jaundice management, consideration is also needed in how to raise awareness of the importance of avoiding severe adverse outcomes, even when they might be rare, and how this might be done. Addressing issues that lead to disjointed care or poor knowledge of neonatal jaundice among health professionals is essential.

Rare cause of jaundice in a term newborn.

Neonatal jaundice is a frequently observed occurrence in full-term newborns and typically manifests between 48 and 96 hours following birth. Early-onset jaundice is primarily induced by pathological factors, namely sepsis, hemolysis and an excessive accumulation of bilirubin resulting from the breakdown of red blood cells.We present a case involving a full-term newborn with an uneventful perinatal history, who exhibited jaundice within the initial day of life and was subsequently admitted to the neonatal intensive care unit to commence intensive phototherapy. Initial screenings for sepsis and blood group incompatibility yielded negative results. However, despite 6 hours of phototherapy, the bilirubin levels did not decrease, prompting an investigation into central nervous system haemorrhage, which uncovered the presence of a haemorrhagic stroke.After a worsening in neurological status with neonatal crisis and need for phenobarbital, a life-saving craniotomy was performed. Clinical evolution was good with no additional crisis detected after the early neonatal period and improvement in motor function at 2-month-old follow-up.

A National Review of Neonatal Jaundice Identification.

Background Physiological neonatal hyperbilirubinemia is a normal transitional phenomenon, however bilirubin encephalopathy can develop due to exposure to very high bilirubin levels. A systematic approach to early detection of high levels can prevent this outcome. Methods We designed a questionnaire to assess local jaundice management practices in Irish maternity units. Results All 19 units responded to our clinical questionnaire. Early discharge (<48 hours) occurs in 12 units (63%). Six units universally screen all babies with a transcutaneous bilirubinometer (TCB) (32%) while 12 units only do so if clinically jaundiced (83%). 12 units follow up <5% of their babies for jaundice monitoring after discharge (67%), which is lower than expected for optimal jaundice management. Conclusion Our survey responses show a high degree of variability in jaundice identification and follow up practices around the country. As maternity units trend towards earlier discharge of mothers due to resource constraints, we need to develop national systems to stratify risk before discharge and monitor jaundice in the out-patient setting. Introduction

Comparison of Transcutaneous and Total Serum Bilirubin Measurements at Five Different Sites in Newborns before and after Phototherapy.

OBJECTIVE: This study aims to examine the accuracy of transcutaneous bilirubin (TcB) in estimating the total serum bilirubin (TSB) level at five different sites before and immediately after phototherapy. METHODS: This study prospectively enrolled infants with a gestational age of 34 to 416/7 weeks who were clinically diagnosed with neonatal jaundice and required phototherapy within 28 days after birth. TcB levels were measured on the uncovered four areas (forehead, mid-sternum, abdomen, and interscapular site) and covered hipbone by using the Dräger JM-103 Jaundice Meter before phototherapy and at 0 min after discontinuing phototherapy. Correlation and agreement between TcB and TSB levels were assessed before and after phototherapy. RESULTS: We included 108 infants with a mean gestational age of 37.6±1.5 weeks and birth weight of 3108±548 g. A strong significant correlation was found between TSB and TcB measurements at all five sites before phototherapy with the strongest correlation at the interscapular site (r=0.768, p=0.001). The correlation was weakened between TSB and TcB at all five sites after phototherapy; however, the strongest correlation was at the covered hipbone (r=0.619, p=0.001). TcB measurements at all five sites tended to underestimate TSB levels before and after phototherapy. The difference (TcB - TSB) tended to increase with increasing TSB levels. CONCLUSIONS: TcB levels were most accurately measured at the interscapular site and covered hipbone before and immediately after phototherapy, respectively.

A Significant Increase in the Incidence of Neonatal Hyperbilirubinemia and Phototherapy Treatment Due to a Routine Change in Laboratory Equipment.

CONTEXT.­: Total serum bilirubin (TSB) analysis is pivotal for diagnosing neonatal hyperbilirubinemia. Because of a routine change in laboratory equipment, our TSB assay changed from a diazo to a vanadate oxidase method. Upon implementation, TSB results were substantially higher in newborns than expected based on the validation. OBJECTIVE.­: To investigate the application of TSB and intermethod differences in neonates and their impact on phototherapy treatment. DESIGN.­: The diazo and vanadate methods were compared directly using neonatal and adult samples. Anonymized external quality control data were analyzed to explore interlaboratory differences among 8 commercial TSB assays. Clinical patient data were extracted from the medical records to investigate the number of newborns receiving phototherapy. RESULTS.­: The mean bias of the vanadate versus the diazo TSB method was +17.4% and +3.7% in neonatal and adult samples, respectively. External quality control data showed that the bias of commercial TSB methods compared with the reference method varied from -3.6% to +20.2%. Within-method variation ranged from 5.2% to 16.0%. After implementation of the vanadate TSB method, the number of neonates treated with phototherapy increased approximately threefold. CONCLUSIONS.­: Currently available TSB assays lack harmonization for the diagnosis of neonatal hyperbilirubinemia. Between-methods differences are substantially higher in neonatal compared with adult samples, highlighting the importance of including neonatal samples during assay validation. Close collaboration between laboratory specialists and clinicians is essential to prevent overtreatment or undertreatment upon the implementation of novel analyzers or assays. Also, harmonization of TSB assays, with an emphasis on neonatal application, is warranted.

Monitoring gestational diabetes mellitus patients with myDiabby Healthcare® smartphone application vs classical diary. Results from the non-inferiority TELESUR-GDM study.

OBJECTIVE: The aim of the TELESUR-GDM study was to demonstrate the non-inferiority of the onset of maternal, fœtal, and neonatal complications for patients with gestational diabetes mellitus (GDM) monitored by myDiabby HealthcareⓇ (app group) compared to patients with a classical glycaemic blood monitoring by diary (control group). MATERIALS AND METHODS: TELESUR-GDM was a retrospective, monocentric, and non-inferiority study including 349 patients in the app group and 295 patients in the control group. The primary outcome was a composite score based on maternal, foetal, and neonatal complications. The statistical analysis used chi square or Student t tests for categorical or continuous variables, and Dunnett-Gent test for non-inferiority. RESULTS: In the app and control groups, 46.3 % and 53.7 % of the patients respectively, observed complications. Non-inferiority of telemonitoring by application vs diary was confirmed (odds ratio=0.79 [95 % CI 0.58;1.07], P < 0.001). Caesarean section, labour induction, and insulin treatment rates were: 20 vs 23 % (P = 0.4), 36 vs 28 % (P = 0.047), and 22 vs 23 % (P = 0.8) in the app vs control group, respectively. Macrosomia, intrauterine growth restriction, neonatal hypoglycaemia, and neonatal jaundice rates were: 4.3 vs 6.1 % (P = 0.4), 6.9 vs 3.1 % (P = 0.04), 1.7 vs 14 % (P < 0.001), and 8.6 vs 1.0 % (P < 0.001), in the app versus control group, respectively. CONCLUSION: GDM glycaemic telemonitoring compared to patients with classic glycaemic monitoring by diary was not inferior in terms of maternal, fœtal, and neonatal complications. Neonatal hypoglycaemia, a life-threatening event, was significantly reduced despite the observation of more neonatal jaundice cases.

Risk factors and clinical correlates of sensory dysfunction in preschool children with and without autism spectrum disorder.

Sensory dysfunction is a common feature of autism spectrum disorder (ASD). The objectives of this analysis were to examine risk factors and clinical correlates of sensory dysfunction in preschool children with and without ASD. Children aged 2-5 years were enrolled in a multi-site case-control study. Data were collected in eight areas across the United States in three phases. Caregivers completed an interview with questions on assisted delivery, maternal alcohol use, maternal anxiety during pregnancy, pregnancy weight gain, neonatal jaundice, preterm birth, and child sensory diagnosis given by a healthcare provider. Caregivers also completed an interview and questionnaires on sensory symptoms and clinical correlates of sensory dysfunction in their child. There were 2059 children classified as ASD, 3139 as other developmental delay or disability (DD), and 3249 as population comparison (POP). Caregivers reported significantly more sensory diagnoses and sensory symptoms in children classified as ASD than DD or POP (23.7%, 8.6%, and 0.8%, respectively, for a sensory diagnosis and up to 78.7% [ASD] vs. 49.6% [DD] for sensory symptoms). Maternal anxiety during pregnancy and neonatal jaundice were significantly associated with a sensory diagnosis and certain sensory symptoms in children with ASD and DD. Children's anxiety, attention deficits/hyperactivity, and sleep problems were significantly albeit subtly correlated with both a sensory diagnosis and sensory symptoms in children with ASD and DD. These findings support sensory dysfunction as a distinguishing symptom of ASD in preschool children and identify risk factors and clinical correlates to inform screening and treatment efforts in those with atypical development.

Accuracy of transcutaneous bilirubinometry in term infants after phototherapy: a prospective observational study.

OBJECTIVE: To test the accuracy of transcutaneous bilirubinometry (TcB) in neonates 12 h after discontinuing phototherapy. STUDY DESIGN: In a prospective study of 91 neonates at ≥35 weeks of gestation, paired measurements of total serum bilirubin (TSB) and TcB were obtained 12 h after discontinuation of phototherapy. TcB measurements were obtained on the uncovered skin of the sternum and the covered skin of the lower abdomen. Bland-Altman plots were used to evaluate agreement between TSB and TcB. RESULTS: TcB was found to systematically underestimate TSB on both covered and uncovered skin. The smallest but statistically significant difference between TSB and TcB was found on the covered lower abdomen (-1.03, p < .0001) compared with the uncovered skin of the sternum (-1.44, p < .0001). The correlation between TSB and TcB was excellent on both covered (r = 0.86, p < .001) and uncovered skin (r = 0.90, p < .001). Bland and Altman plots showed poor agreement between TcB and TSB. CONCLUSIONS: This study demonstrated excellent correlation between TcB and TSB 12 h after phototherapy but poor TcB-TSB agreement. TcB cannot be reliably used in neonates exposed to phototherapy.