Screening methods for neonatal hyperbilirubinemia: benefits, limitations, requirements, and novel developments

Bilirubin: Photophysical and photochemical properties, phototherapy, analytical methods of measurement. A short review

Bilirubin, a yellow bile pigment, plays an important role in the body, being a potent antioxidant and having anti-inflammatory, immunomodulatory, cytoprotective, and neuroprotective functions. This makes bilirubin promising as a therapeutic and diagnostic agent in biomedicine. However, excess bilirubin is toxic and should be removed from the body. Bilirubin exhibits photochemical activity, which has been the subject of numerous studies up to now. Such studies are relevant because the bilirubin photochemistry provides the basis for bilirubin removing in phototherapy of neonatal jaundice (neonatal hyperbilirubinemia) and for some therapeutic applications. Furthermore, it can model several elementary processes of molecular photonics. In particular, the bilirubin molecule is capable of ultrafast Z-E photoisomerization and contains two almost identical dipyrromethenone chromophores capable of exciton coupling. The present review considers the data on the photophysical and photochemical properties of bilirubin and ultrafast routes of its phototransformations, as well as its photochemical reactions in phototherapy of neonatal hyperbilirubinemia and the ways to decrease the possible adverse effects of the phototherapy. The main analytical methods of bilirubin measurement in biological systems are also viewed.

Implementation of the Revised American Academy of Pediatrics Clinical Practice Guidelines for Hyperbilirubinemia Decreases Necessity for Serum Bilirubin and Phototherapy

BACKGROUND

The initial hyperbilirubinemia management recommendations published by the American Academy of Pediatrics (AAP) in 2004 and updated in 2009 led to wide variations in clinical practice among providers, with variable results. In August 2022 AAP published updated clinical practice guidelines for the management of hyperbilirubinemia. The aim of this project was to determine the effect of adaptation of the AAP guidelines on laboratory testing, readmission rates, and phototherapy.

METHODS

Existing institutional protocol was updated to incorporate the revised AAP guidelines. The primary outcome was percentage of serum bilirubin labs obtained. Balancing measures included monthly readmission rate, need for escalation of care, and percentage of patients requiring additional labs or phototherapy. Statistical process control charts measured changes in quality over time. Chi-square analysis evaluated differences between pre- and postintervention periods.

RESULTS

A total of 2,301 infants were evaluated, 1,662 of which were included in the postintervention analysis. A clinically and statistically significant decrease was seen in the percentage of patients with serum bilirubin evaluation, from 21.3% to 8.8% (p < 0.001). There was a decrease in need for phototherapy, from 4.2% to 1.4% (p < 0.001), but duration of treatment was longer when initiated. The authors simultaneously saw no changes in readmission rate or additional laboratory evaluation, with no incidence of bilirubin-induced encephalopathy or escalation of care.

CONCLUSION

Implementation of the revised 2022 AAP guidelines was associated with a decrease in serum bilirubin evaluation and phototherapy initiation. This integrated protocol may represent a sustainable standardized approach to management of hyperbilirubinemia.

Can smartphone cameras help with diagnostic adequacy in renal biopsy?

BACKGROUND

In this prospective study, we evaluated whether a sufficient number of glomeruli were achieved using the 8× magnification of smartphone cameras.

PURPOSE

To increase the percutaneous ultrasound-guided renal biopsy (PURB) diagnostic value with a method that has not been tried before and reduce the need for repetition of the procedure.

MATERIAL AND METHODS

A total of 39 adult patients who underwent PURB were included in our study. After the PURB was applied to the patients, the biopsy specimen was placed on the previously prepared sterile gauze. At this stage, 8× magnification photos were taken of the biopsy samples using the smartphone camera. The glomeruli in the photograph were counted and recorded and compared with the number of glomeruli seen at the end of the histopathological examination.

RESULTS

The mean number of glomeruli in the evaluated samples was counted as 6 ± 2.2 (range = 1-10) in the 8× magnification photograph. The mean number of glomeruli detected in the histopathological examination of these samples was 11 ± 5.7 (range = 2-30). A pathological glomeruli count of 10 was associated with more than five brown spots in the 8× magnification photograph (area under the curve = 0.977, P=0.0001).

CONCLUSION

To obtain more than 10 glomeruli in a PURB specimen, five or more brownish-red dots should be counted on the 8x magnification photograph. Using smartphones as an alternative tool for evaluating renal biopsy tissue adequacy can be practical and advantageous in terms of time and labor.

Development and Validation of a Smartphone Application for Neonatal Jaundice Screening

Importance

This diagnostic study describes the merger of domain knowledge (Kramer principle of dermal advancement of icterus) with current machine learning (ML) techniques to create a novel tool for screening of neonatal jaundice (NNJ), which affects 60% of term and 80% of preterm infants.

Objective

This study aimed to develop and validate a smartphone-based ML app to predict bilirubin (SpB) levels in multiethnic neonates using skin color analysis.

Design, Setting, and Participants

This diagnostic study was conducted between June 2022 and June 2024 at a tertiary hospital and 4 primary-care clinics in Singapore with a consecutive sample of neonates born at 35 or more weeks' gestation and within 21 days of birth.

Exposure

The smartphone-based ML app captured skin images via the central aperture of a standardized color calibration sticker card from multiple regions of interest arranged in a cephalocaudal fashion, following the Kramer principle of dermal advancement of icterus. The ML model underwent iterative development and k-folds cross-validation, with performance assessed based on root mean squared error, Pearson correlation, and agreement with total serum bilirubin (TSB). The final ML model underwent temporal validation.

Main Outcomes and Measures

Linear correlation and statistical agreement between paired SpB and TSB; sensitivity and specificity for detection of TSB equal to or greater than 17mg/dL with SpB equal to or greater than 13 mg/dL were assessed.

Results

The smartphone-based ML app was validated on 546 neonates (median [IQR] gestational age, 38.0 [35.0-41.0] weeks; 286 [52.4%] male; 315 [57.7%] Chinese, 35 [6.4%] Indian, 169 [31.0%] Malay, and 27 [4.9%] other ethnicities). Iterative development and cross-validation was performed on 352 neonates. The final ML model (ensembled gradient boosted trees) incorporated yellowness indicators from the forehead, sternum, and abdomen. Temporal validation on 194 neonates yielded a Pearson r of 0.84 (95% CI, 0.79-0.88; P < .001), 82% of data pairs within clinically acceptable limits of 3 mg/dL, sensitivity of 100%, specificity of 70%, positive predictive value of 10%, negative predictive value of 100%, positive likelihood ratio of 3.3, negative likelihood ratio of 0, and area under the receiver operating characteristic curve of 0.89 (95% CI, 0.82-0.96).

Conclusions and Relevance

In this diagnostic study of a new smartphone-based ML app, there was good correlation and statistical agreement with TSB with sensitivity of 100%. The screening tool has the potential to be an NNJ screening tool, with treatment decisions based on TSB (reference standard). Further prospective studies are needed to establish the generalizability and cost-effectiveness of the screening tool in the clinical setting.

Development of Non-Invasive Biosensors for Neonatal Jaundice Detection: A Review

One of the most common problems many babies encounter is neonatal jaundice. The symptoms are yellowing of the skin or eyes because of bilirubin (from above 2.0 to 2.5 mg/dL in the blood). If left untreated, it can lead to serious neurological complications. Traditionally, jaundice detection has relied on invasive blood tests, but developing non-invasive biosensors has provided an alternative approach. This systematic review aims to assess the advancement of these biosensors. This review discusses the many known invasive and non-invasive diagnostic modalities for detecting neonatal jaundice and their limitations. It also notes that the recent research and development on non-invasive biosensors for neonatal jaundice diagnosis is still in its early stages, with the majority of investigations being in vitro or at the pre-clinical level. Non-invasive biosensors could revolutionize neonatal jaundice detection; however, a number of issues still need to be solved before this can happen. These consist of in-depth validation studies, affordable and user-friendly gadgets, and regulatory authority approval. To create biosensors that meet regulatory requirements, additional research is required to make them more precise and affordable.

Performance of smartphone application to accurately quantify hyperbilirubinemia in neonates: a systematic review with meta-analysis

Neonatal jaundice is a common clinical condition that can progress to severe hyperbilirubinemia if identification and intervention are delayed. In this study, we aimed to analyze the current evidence on the accurate performance of smartphone applications to quantify bilirubin levels. PubMed, Embase, Emcare, MEDLINE, the Cochrane Library, and Google Scholar were searched from inception until July 2022. Grey literature was searched on "OpenGrey" and "MedNar" databases. We included prospective and retrospective cohort studies that recruited infants with a gestation of ≥ 35 weeks and reported paired total serum bilirubin (TSB) and smartphone app-based bilirubin (ABB) levels. We conducted the review using the guidelines of the Cochrane Collaboration Diagnostic Test Accuracy Working Group and reported using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses-diagnostic test accuracy (PRISMA-DTA) statement. The data were pooled using the random effects model. The outcome of interest was agreement between ABB and TSB measurements, provided as correlation coefficient, mean difference, and standard deviation. Certainty of evidence (COE) was assessed based on GRADE guidelines. Fourteen studies were included in the meta-analysis. The number of infants in individual studies ranged between 35 and 530. The pooled correlation coefficient (r) between ABB and TSB was 0.77 (95% CI 0.69 to 0.83; p < 0.01). Reported sensitivities for predicting a TSB of 250 µmol/L in individual studies ranged between 75 and 100% and specificities ranged from 61 to 100%. Similarly, a sensitivity of 83 to 100% and a specificity of 19.5 to 76% were reported for predicting a TSB of 205 μmol/L. Overall COE was considered moderate.    Conclusion: Smartphone app-based bilirubin estimation showed a reasonable correlation to TSB levels. Well-designed studies are required to determine its utility as a screening tool for various TSB cut-off levels. What is Known: • Neonatal jaundice is a common clinical condition. Timely screening and intervention are necessary to prevent neurological morbidities • Transcutaneous bilirubinometer is a widely used non-invasive screening device but is mostly available in hospital settings and has cost limitations. Researchers have recently explored the utility of smartphone applications to estimate bilirubin levels in neonates. What is New: • This is the first systematic review and meta-analysis conducted to assess the performance of smartphone applications to detect neonatal hyperbilirubinemia. • Bilirubin estimates of newborn infants obtained through smartphone applications had a reasonable correlation with serum bilirubin levels.

The use of transcutaneous bilirubin nomograms for the prevention of bilirubin neurotoxicity in the neonates

Purpose

Although neonatal jaundice is a ubiquitous and predominantly benign phenomenon, the risk of neurotoxicity exists in a number of infants with unconjugated hyperbilirubinemia. Plotting bilirubin values on nomograms enables clinicians to employ an anticipatory and individualized approach with the goal of avoiding excessive hyperbilirubinemia and preventing acute bilirubin encephalopathy and its progression to kernicterus. We aimed to construct nomograms for White term infants based on transcutaneous bilirubin (TcB) measurements using a JM-105 device.

Methods

TcB measurements were taken in infants at ages ranging from 0 to 96 postnatal hours. We then constructed hour-specific TcB nomograms from forehead and sternum measurements in infants who did not require subsequent phototherapy.

Results

We included 2,981 TcB measurements taken on the forehead and 2,977 measurements taken on the sternum in 301 White term newborn infants. We assessed the predictive abilities of the nomograms at six postnatal time intervals using receiver operating characteristic curves. The areas under the curves indicated reasonable prediction of hyperbilirubinemia requiring phototherapy, except for the forehead measurement taken within the first 12 h of life. Sensitivity tended to rise as postnatal age increased.

Conclusion

The nomograms illustrate dermal bilirubin dynamics in White term neonates during the first 4 days of life. They may be useful tools to predict individualized risk of hyperbilirubinemia requiring treatment, and to plan optimal follow-up of infants at risk of bilirubin neurotoxicity.

Parental detection of neonatal jaundice using a low-cost colour card: a multicentre prospective study

BACKGROUND

Since most infants are usually discharged before age 48-72 hours, peak bilirubin levels will almost always occur after discharge. Parents may be the first to observe the onset of jaundice after discharge, but visual assessment is unreliable. The jaundice colour card (JCard) is a low-cost icterometer designed for the assessment of neonatal jaundice. The objective of this study was to evaluate parental use of JCard to detect jaundice in neonates.

METHODS

We conducted a multicentre, prospective, observational cohort study in nine sites across China. A total of 1161 newborns ≥35 weeks of gestation were enrolled in the study. Measurements of total serum bilirubin (TSB) levels were based on clinical indications. The JCard measurements by parents and paediatricians were compared with the TSB.

RESULTS

JCard values of parents and paediatricians were correlated with TSB (r=0.754 and 0.788, respectively). The parents' and paediatricians' JCard values 9 had sensitivities of 95.2% vs 97.6% and specificities of 84.5% vs 71.7% for identifying neonates with TSB ≥153.9 µmol/L. The parents' and paediatricians' JCard values 15 had sensitivities of 79.9% vs 89.0% and specificities of 66.7% vs 64.9% for identifying neonates with TSB ≥256.5 µmol/L. Areas under the receiver operating characteristic curves of parents for identifying TSB ≥119.7, ≥153.9, ≥205.2, and ≥256.5 µmol/L were 0.967, 0.960, 0.915, and 0.813, respectively, and those of paediatricians were 0.966, 0.961, 0.926 and 0.840, respectively. The intraclass correlation coefficient was 0.933 between parents and paediatricians.

CONCLUSION

The JCard can be used to classify different levels of bilirubin, but it is less accurate with high bilirubin levels. The JCard diagnostic performance of parents was slightly lower than that of paediatricians.

Management challenges in the treatment of severe hyperbilirubinemia in low- and middle-income countries: Encouraging advancements, remaining gaps, and future opportunities

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.

Better assessment of neonatal jaundice at home (BEAT Jaundice @home): protocol for a prospective, multicentre diagnostic study

INTRODUCTION

Severe neonatal hyperbilirubinaemia can place a neonate at risk for acute bilirubin encephalopathy and kernicterus spectrum disorder. Early diagnosis is essential to prevent these deleterious sequelae. Currently, screening by visual inspection followed by laboratory-based bilirubin (LBB) quantification is used to identify hyperbilirubinaemia in neonates cared for at home in the Netherlands. However, the reliability of visual inspection is limited. We aim to evaluate the effectiveness of universal transcutaneous bilirubin (TcB) screening as compared with visual inspection to: (1) increase the detection of hyperbilirubinaemia necessitating treatment, and (2) reduce the need for heel pricks to quantify bilirubin levels. In parallel, we will evaluate a smartphone app (Picterus), and a point-of-care device for quantifying total bilirubin (Bilistick) as compared with LBB.

METHODS AND ANALYSIS

We will undertake a multicentre prospective cohort study in nine midwifery practices across the Netherlands. Neonates born at a gestational age of 35 weeks or more are eligible if they: (1) are at home at any time between days 2 and 8 of life; (2) have their first midwife visit prior to postnatal day 6 and (3) did not previously receive phototherapy. TcB and the Picterus app will be used after visual inspection. When LBB is deemed necessary based on visual inspection and/or TcB reading, Bilistick will be used in parallel. The coprimary endpoints of the study are: (1) hyperbilirubinaemia necessitating treatment; (2) the number of heel pricks performed to quantify LBB. We aim to include 2310 neonates in a 2-year period. Using a decision tree model, a cost-effectiveness analysis will be performed.

ETHICS AND DISSEMINATION

This study has been approved by the Medical Research Ethical Committee of the Erasmus MC Rotterdam, Netherlands (MEC-2020-0618). Parents will provide written informed consent. The results of this study will be published in peer-reviewed journals.

TRIAL REGISTRATION NUMBER

Dutch Trial Register (NL9545).

Maternal Blood Group and Routine Direct Antiglobulin Testing in Neonates: Is There a Role for Selective Neonatal Testing?

Recommendations for the screening of hemolytic disease of the newborn (HDN) advise taking a selective approach in using the direct antiglobulin test (DAT) for mothers with blood group O or RhD-negative. This study assessed the relation of DAT results to maternal and neonatal blood groups and evaluated the risk of HDN. A retrospective analysis of all healthy newborns admitted during 2018 was performed. Of 1463 newborns, 4.4% had a positive DAT. There were 541 (37%) maternal–neonatal pairs with ABO incompatibility, most commonly born to mothers with blood group O. The cohort of neonates born to mothers with blood group O was divided into three groups: the O-A and O-B groups and the O-O group as a control. The DAT was positive in 59 (8.3%) neonates; most were in the O-B group (49.2%), whereas 13.6% were in the control group (p < 0.01). While the neonates in the O-B group were more likely to require phototherapy (p = 0.03), this finding was not related to DAT results. We found that selective testing of mothers with blood group O, mothers with blood group O or RhD-negative, neonates with blood group B, and neonates with blood group B born to mothers with blood group O or RhD-negative was ineffective in detecting phototherapy requirements. Our results indicate no difference regarding the need for phototherapy in neonates born to mothers with different blood types regardless of the DAT results.