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

Computational Approaches for Predicting Preterm Birth and Newborn Outcomes

Preterm birth (PTB) and its associated morbidities are a leading cause of infant mortality and morbidity. Accurate predictive models and a better biological understanding of PTB-associated morbidities are critical in reducing their adverse effects. Increasing availability of multimodal high-dimensional data sets with concurrent advances in artificial intelligence (AI) have created a rich opportunity to gain novel insights into PTB, a clinically complex and multifactorial disease. Here, the authors review the use of AI to analyze 3 modes of data: electronic health records, biological omics, and social determinants of health metrics.

Intravenous immunoglobulin G therapy for neonatal hyperbilirubinemia

BACKGROUND

Neonatal hyperbilirubinemia (NHb) results from increased total serum bilirubin and is a common reason for admission and readmission amongst newborn infants born in North America. The use of intravenous immunoglobulin (IVIG) therapy for treating NHb has been widely debated, and the current incidence of NHb and its therapies remain unknown.

METHODS

Using national and provincial databases, a population-based retrospective cohort study of infants born in Ontario from April 2014 to March 2018 was conducted.

RESULTS

Of the 533,084 infants born in Ontario at ≥35 weeks gestation, 29,756 (5.6%) presented with NHb. Among these infants, 80.1-88.2% received phototherapy, 1.1-2.0% received IVIG therapy and 0.1-0.2% received exchange transfusion (ET) over the study period. Although phototherapy was administered (83.0%) for NHb, its use decreased from 2014 to 2018 (88.2-80.1%) (P < 0.01). Similarly, the incidence of IVIG therapy increased from 71 to 156 infants (1.1-2.0%) (P < 0.01) and a small change in the incidence of ET (0.2-0.1%) was noted.

CONCLUSION

IVIG therapy is increasingly being used in Ontario despite limited studies evaluating its use. The results of this study could inform treatment and management protocols for NHb.

IMPACTS

Clinically significant neonatal hyperbilirubinemia still occurs in Ontario, with an increasing number of infants receiving Intravenous Immunoglobulin G (IVIG) therapy. IVIG continues to be used at increasing rates despite inconclusive evidence to recommend its use. This study highlights the necessity of a future prospective study to better determine the effectiveness of IVIG use in treating neonatal hyperbilirubinemia, especially given the recent shortage in IVIG supply in Ontario. The results of this study could inform treatment and management protocols for neonatal hyperbilirubinemia.

Age-specific reference intervals for liver function tests in healthy neonates, infants, and young children in Iran

BACKGROUND

The reference intervals (RIs) for liver function tests (LFTs) were determined in Iranian children for the first time.

METHODS

A total of 344 healthy pediatrics aged 3 days to 30 months old were recruited. Serum levels of ALT, AST, ALP, direct bilirubin, and total bilirubin were measured. RIs were determined using CLSI Ep28-A3 guidelines.

RESULTS

All analytes demonstrated age-specific differences except AST. ALT and ALP demonstrated significantly elevated levels in infants 0 to <5 months relative to the remainder of the age range. Direct and total bilirubin demonstrated markedly elevated levels in early life with mean of 0.28 mg/dL and 1.64 mg/dL observed for direct and total bilirubin, respectively, decreasing by ~50% in the adjacent partition.

CONCLUSION

These novel data will help improve the clinical interpretation of biochemical test results in young Iranian neonates and children and can be of value to clinical laboratories with similar populations.

Validating the early phototherapy prediction tool across cohorts

Background

Hyperbilirubinemia of the newborn infant is a common disease worldwide. However, recognized early and treated appropriately, it typically remains innocuous. We recently developed an early phototherapy prediction tool (EPPT) by means of machine learning (ML) utilizing just one bilirubin measurement and few clinical variables. The aim of this study is to test applicability and performance of the EPPT on a new patient cohort from a different population.

Materials and methods

This work is a retrospective study of prospectively recorded neonatal data from infants born in 2018 in an academic hospital, Regensburg, Germany, meeting the following inclusion criteria: born with 34 completed weeks of gestation or more, at least two total serum bilirubin (TSB) measurement prior to phototherapy. First, the original EPPT-an ensemble of a logistic regression and a random forest-was used in its freely accessible version and evaluated in terms of the area under the receiver operating characteristic curve (AUROC). Second, a new version of the EPPT model was re-trained on the data from the new cohort. Third, the predictive performance, variable importance, sensitivity and specificity were analyzed and compared across the original and re-trained models.

Results

In total, 1,109 neonates were included with a median (IQR) gestational age of 38.4 (36.6-39.9) and a total of 3,940 bilirubin measurements prior to any phototherapy treatment, which was required in 154 neonates (13.9%). For the phototherapy treatment prediction, the original EPPT achieved a predictive performance of 84.6% AUROC on the new cohort. After re-training the model on a subset of the new dataset, 88.8% AUROC was achieved as evaluated by cross validation. The same five variables as for the original model were found to be most important for the prediction on the new cohort, namely gestational age at birth, birth weight, bilirubin to weight ratio, hours since birth, bilirubin value.

Discussion

The individual risk for treatment requirement in neonatal hyperbilirubinemia is robustly predictable in different patient cohorts with a previously developed ML tool (EPPT) demanding just one TSB value and only four clinical parameters. Further prospective validation studies are needed to develop an effective and safe clinical decision support system.

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.

Correlation between hyperbilirubinemia risk and immune cell mitochondria parameters in neonates with jaundice

Purpose

To explore the correlation between mitochondria parameters of immune cells and hyperbilirubinemia risk in hospitalized neonates with jaundice.

Methods

This retrospective study included jaundiced neonates born between September 2020 and March 2022 at Shaoxing Keqiao Women & Children's Hospital. The neonates were divided into low, intermediate-low, intermediate-high, and high-risk groups according to the hyperbilirubinemia risk. The purpose parameters including percentage, absolute count, mitochondrial mass (MM), and single-cell MM (SCMM) of peripheral blood T lymphocytes detected by flow cytometry were collected.

Results

Finally, 162 neonates with jaundice (47, 41, 39, and 35 with low, intermediate-low, intermediate-high, and high-risk) were included. CD3⁺ SCMM was significantly higher in the high-risk group compared with the low and intermediate-low-risk groups (both P < 0.0083), CD4⁺ SCMM was significantly higher in the high-risk group compared with the three other groups (all P < 0.0083), and CD8⁺ SCMM was significantly higher in the intermediate-low and high-risk groups compared with the low-risk group (both P < 0.0083). CD3⁺ (r = 0.34, P < 0.001) and CD4⁺ (r = 0.20, P = 0.010) SCMM positively correlated with bilirubin levels.

Conclusions

The mitochondrial SCMM parameters differed significantly among jaundiced neonates with different hyperbilirubinemia risks. CD3⁺ and CD4⁺ T cell SCMM values were positively correlated with the serum bilirubin levels, and might correlated with hyperbilirubinemia risk.

The Relationship between Psychological Suffering, Value of Maternal Cortisol during Third Trimester of Pregnancy and Breastfeeding Initiation

Background and Objectives: Cortisol, the stress hormone, is an important factor in initiating and maintaining lactation. Maternal suffering during pregnancy is predictive for the initiation and shorter duration of breastfeeding and can also lead to its termination. The aim of this study is to evaluate the relationship between the level of salivary cortisol in the third trimester of pregnancy and the initiation of breastfeeding in the postpartum period in a cohort of young pregnant women who wanted to exclusively breastfeed their newborns during hospitalization. Materials and Methods: For the study, full-term pregnant women were recruited between January and May 2022 in the Obstetrics and Gynecology Clinic of the Mureș County Clinical Hospital. Socio-demographic, clinical obstetric and neonatal variables were collected. Breastfeeding efficiency was assessed using the LATCH Breastfeeding Assessment Tool at 24 and 48 h after birth. The mean value of the LATCH score assessed at 24 and 48 h of age was higher among mothers who had a higher mean value of salivary cortisol measured in the third trimester of pregnancy (p < 0.05). A multivariate logistic regression model was used to detect risk factors for the success of early breastfeeding initiation. Results: A quarter of pregnant women had a salivary cortisol level above normal limits during the third trimester of pregnancy. There is a statistically significant association between maternal smoking, alcohol consumption during pregnancy and the level of anxiety or depression. Conclusions: The most important finding of this study was that increased salivary cortisol in the last trimester of pregnancy was not associated with delayed initiation/absence of breastfeeding.

Bilirubin Levels in Neonates ≥35 Weeks of Gestation Receiving Delayed Cord Clamping for an Extended Time-An Observational Study

OBJECTIVE

To describe bilirubin levels in neonates ≥35^0/7 gestational weeks, receiving delayed cord clamping (CC), in relation to the updated Bhutani nomogram.

STUDY DESIGN

This was a retrospective, observational study based on data from medical records and local data sheets. Singleton neonates, born vaginally at a gestational age ≥35^0/7, and with a registered time to CC and at least one registered bilirubin, were included. We excluded neonates with positive direct antiglobulin test or hemolytic disorders. Adjusted analyses were performed using ANOVA and linear or logistic regression.

RESULTS

We analyzed 558 neonates, mean gestational age (SD) 39.9 (1.3) weeks. CC was performed at a median (IQR) time of 6 (5-8) minutes. The dataset contained 1330 bilirubin measurements. Median (IQR) age at bilirubin measurement was 37 (22-54) hours. Bilirubin percentiles in neonates with CC time ≥2 minutes were similar, or lower, compared with the Bhutani nomogram between 12 and 72 hours, but with greater 95th percentile at later hours of age. Phototherapy was initiated in 13 (2.3 %) of the neonates. We found no association between time to CC and hyperbilirubinemia (β = -0.05, P = .07). Need for phototherapy was marginally greater in neonates with shorter time to CC.

CONCLUSIONS

Bilirubin levels were not correlated to time to CC. Our findings indicate that CC beyond 2 minutes can be performed without additional monitoring for jaundice.

Development and evaluation of a novel method "bilirubin color card" for screening of treatable jaundice in neonates: prospective comparative diagnostic study

BACKGROUND

Various methods of screening or diagnosis of severe hyperbilirubinemia like transcutaneous bilirubinometer and laboratory testing havemethodological or practical limitations. In this perspective, we designed and evaluated an invasive but simple screening Color Card method in rapid assessment of various levels of bilirubin categories.

OBJECTIVE

This prospective comparative diagnostic study objectives were to create "Color Card" initially by yellow color shades that fall into 4 bilirubin categories, i.e. TSB up to 7 mg/dl, 7.1 to 12 mg/dl, 12.1 to 18 mg/dl and >18 mg/dl from the samples analyzed by diazo method, and to study its sensitivity and specificity for the diagnosis of moderate or severe hyperbilirubinemia in comparison to total serum bilirubin (TSB) by diazo method.

RESULTS

Out of total 188 samples obtained, 134 were unique patients. The specificity, negative predictive value and accuracy of the color card for the observations made by observer 1 comparing with lab TSB were >95% for clinically important categories of <7 mg/dl and >18 mg/dl. The overall accuracy of color card in measuring various TSB ranges varied from 75% to 96.8%. The agreement between two observers was 85.6% (Cohen's kappa co-efficient: 0.61, p-value: .0001) overall and was 92.3%, 86%, 84%, 81.2% for each of the four bilirubin categories in ascending order.

CONCLUSION

Bilirubin color card has good accuracy and may be very useful in the low resource settings, especially in the first referral units and community settings, where laboratory TSB estimation is not available easily. However, it requires centrifugation and easier methods of centrifugation will make this method simpler.

Applicability of the hour of life approach in hyperbilirubinemia among Filipino term infants

BACKGROUND

Hyperbilirubinemia remains a common morbidity among infants. Additional research on bilirubin kinetics and associated risk factors will contribute to providing a more targeted management approach for the Filipino infant.

OBJECTIVE

To develop a Filipino bilirubin nomogram by studying bilirubin patterns during the first 5 days of life.

METHODOLOGY

This prospective study recruited 1,412 stable, full-term infants (≥37 weeks age of gestation) born at the Philippine General Hospital (PGH). Using the Dräger-Minolta JM-103 jaundice meter, transcutaneous bilirubin (TcB) levels were determined at the 3rd, 6th, 12th, 24th, 36th, 48th, 72nd, 96th, and 120th hour of life (HOL). A bilirubin nomogram was created using the averages of 3 TcB forehead and sternal measurements at each time epoch. Simultaneous measurement of TcB and total serum bilirubin (TsB) on a subset of 106 infants was done to determine correlation.

RESULTS

Correlation coefficients were high between TsB and forehead TcB (r² = 0.88), and between TsB and sternal TcB (r² = 0.91). The Filipino bilirubin nomogram reflected a steep rise until the 48th hour, followed by plateauing of values. Inadequate nursing and bilirubin levels at 12th and 48th HOL were risk factors for developing significant hyperbilirubinemia at 72nd HOL.

CONCLUSION

TcB is a reliable, non-invasive bilirubin screening tool. Among healthy, full-term, Filipino infants, their nomogram features a sudden increase in bilirubin values during the first 48 h, followed by a plateau. To aid in identification of infants at risk for significant hyperbilirubinemia, healthcare providers can assess breastfeeding adequacy and perform bilirubin screening at the 24th-48th HOL. Registration No. (RGAO-2016-0686).