Identifying newborns at risk of significant hyperbilirubinaemia: a comparison of two recommended approaches

A review of existing neonatal hyperbilirubinemia guidelines in Indonesia

Background

Neonatal hyperbilirubinemia is one of the most common conditions for neonate inpatients. Indonesia faces a major challenge in which different guidelines regarding the management of this condition were present. This study aimed to compare the existing guidelines regarding prevention, diagnosis, treatment and monitoring in order to create the best recommendation for a new hyperbilirubinemia guideline in Indonesia.

Methods

Through an earlier survey regarding adherence to the neonatal hyperbilirubinemia guideline, we identified that three main guidelines are being used in Indonesia. These were developed by the Indonesian Pediatric Society (IPS), the Ministry of Health (MoH), and World Health Organization (WHO). In this study, we compared factors such as prevention, monitoring, methods for identifying, risk factors in the development of neonatal jaundice, risk factors that increase brain damage, and intervention treatment threshold in the existing guidelines to determine the best recommendations for a new guideline.

Results

The MoH and WHO guidelines allow screening and treatment of hyperbilirubinemia based on visual examination (VE) only. Compared with the MoH and WHO guidelines, risk assessment is comprehensively discussed in the IPS guideline. The MoH guideline recommends further examination of an icteric baby to ensure that the mother has enough milk without measuring the bilirubin level. The MoH guideline recommends referring the baby when it looks yellow on the soles and palms. The WHO and IPS guidelines recommend combining VE with an objective measurement of transcutaneous or serum bilirubin. The threshold to begin phototherapy in the WHO guideline is lower than the IPS guideline while the exchange transfusion threshold in both guidelines are comparably equal.

Conclusions

The MoH guideline is outdated. MoH and IPS guidelines are causing differences in approaches to the management hyperbilirubinemia. A new, uniform guideline is required.

Transcutaneous bilirubinometry versus total serum bilirubin measurement for newborns

BACKGROUND

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

OBJECTIVES

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

SEARCH METHODS

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

SELECTION CRITERIA

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

DATA COLLECTION AND ANALYSIS

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

MAIN RESULTS

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

AUTHORS' CONCLUSIONS

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

Assessment, management, and incidence of neonatal jaundice in healthy neonates cared for in primary care: a prospective cohort study

Jaundice caused by hyperbilirubinaemia is a common phenomenon during the neonatal period. Population-based studies evaluating assessment, management, and incidence of jaundice and need for phototherapy among otherwise healthy neonates are scarce. We prospectively explored these aspects in a primary care setting via assessing care as usual during the control phase of a stepped wedge cluster randomised controlled trial.We conducted a prospective cohort study embedded in the Screening and TreAtment to Reduce Severe Hyperbilirubinaemia in Infants in Primary care (STARSHIP) Trial. Healthy neonates were included in seven primary care birth centres (PCBCs) in the Netherlands between July 2018 and March 2020. Neonates were eligible for inclusion if their gestational age was ≥ 35 weeks, they were admitted in a PCBC for at least  2 days during the first week of life, and if they did not previously receive phototherapy. Outcomes were the findings of visual assessment to detect jaundice, jaundice incidence and management, and the need for phototherapy treatment in the primary care setting.860 neonates were included of whom 608 (71.9%) were visibly jaundiced at some point during admission in the PCBC, with 20 being 'very yellow'. Of the latter, four (20%) did not receive total serum bilirubin (TSB) quantification. TSB levels were not associated with the degree of visible jaundice (p = 0.416). Thirty-one neonates (3.6%) received phototherapy and none received an exchange transfusion. Five neonates did not receive phototherapy despite having a TSB level above phototherapy threshold.Jaundice is common in otherwise healthy neonates cared for in primary care. TSB quantification was not always performed in very jaundiced neonates, and not all neonates received phototherapy when indicated. Quality improvement initiatives are required, including alternative approaches to identifying potentially severe hyperbilirubinaemia.Trial registration: NL6997 (Dutch Trial Register; Old NTR ID 7187), registered 3 May 2018.

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

OBJECTIVE

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

STUDY DESIGN

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

RESULTS

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

CONCLUSIONS

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

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.

Neonatal jaundice: aetiology, diagnosis and treatment

A significant proportion of term and preterm infants develop neonatal jaundice. Jaundice in an otherwise healthy term infant is the most common reason for readmission to hospital. Jaundice is caused by an increase in serum bilirubin levels, largely as a result of breakdown of red blood cells. Bilirubin is conveyed in the blood as 'unconjugated' bilirubin, largely bound to albumin. The liver converts bilirubin into a conjugated form which is excreted in the bile. Very high levels of unconjugated bilirubin are neurotoxic. Phototherapy is a simple and effective way to reduce the bilirubin level. Most term babies have 'physiological' jaundice which responds to a short period of phototherapy, and requires no other treatment. A few babies have rapidly rising bilirubin levels which place them at risk of kernicterus. Current management of jaundice in the UK is guided by the NICE guideline. Any infant with high serum bilirubin or a rapidly rising bilirubin level needs to be treated urgently to avoid neurotoxicity. High levels of conjugated bilirubin in a term baby can indicate biliary atresia, and babies with persisting jaundice must have their level of conjugated bilirubin measured. Preterm infants on long-term parenteral nutrition may develop conjugated jaundice which generally improves with the introduction of enteral feed and weaning of intravenous nutrition.

Umbilical cord bilirubin level and pre-discharge hyperbilirubinemia risk

OBJECTIVES

To assess whether arterial umbilical cord bilirubin (aUCB) level at delivery predicts predischarge neonatal hyperbilirubinemia, facilitating a safe discharge from the hospital.

METHODS

Prospective analysis of hospital biochemistry records identified near term and term infants with recorded aUCB and predischarge, at 36 h of life, capillary heal bilirubin (cHB), to identify those with a cutoff of bilirubin levels >9 mg/ml, >75th percentile on the nomogram of Bhutani et al.

RESULTS

Of 616 study neonates, median (IQR) aUCB and cHB levels were 1.5 mg % (IQR 0.7-2.2) and 7.7 mg % (IQR 6.6-8.9), respectively. The values resulted statistically correlated (Pearson correlation coefficient 0.26, p < .0001) and an increment of 1 mg/dl in aUCB was associated with an increment (Regression coefficient, 95% confidence interval) of mean cHB 0.49 (0.33-0.65, p < .0001). Among these, 143 (23.2%) neonates developed bilirubin levels >9 mg/ml at 36 h of life and multivariable analysis confirmed that cHB levels (OR 1.49, 95% CI 1.22-1.82; p < .0001) and vaginal delivery (OR 2.34, 95% CI 1.33-4.36; p = .005) were significantly associated with bilirubin levels >9 mg/ml.

CONCLUSIONS

These data suggest that aUCB should be added to the list of major risk factors for neonatal hyperbilirubinemia.

Risk Factors Associated with Neonatal Jaundice: A Cross-Sectional Study from Iran

BACKGROUND

Neonatal jaundice is one of the main causes of the patient's admission in the neonatal period and is potentially linked to morbidity.

AIM

This study aimed to determine the possible risk factors for neonatal jaundice.

METHODS

We investigated the case of infants who were admitted to the neonatal department of Ziyaeian hospital and Imam Khomeini Hospital for jaundice. Simple random sampling was used to evaluate variables related to maternal and neonatal predisposing factors based on the medical records and clinical profiles. All variables in this study were analysed using SPSS software.

RESULTS

In this study, about 200 mothers and neonates were examined. Our findings depicted that mother's WBC, Hb, PLT, and gestational age were associated with jaundice (P < 0.05). Furthermore, there were significant relationships between different degrees of bilirubin with TSH, T4 levels and G6PD (P < 0.05). In fact, TSH, T4 levels and G6PD were found to be linked to neonatal hyperbilirubinemia. The risk factors for jaundice in our study population comprise some predisposing factors such as WBC, Hb, PLT, gestational age, TSH, and T4 levels, as well as G6PD. Neonates at risk of jaundice are linked to some maternal and neonatal factors that can provide necessary interventions to reduce the burden of the disease. Therefore, identification of associated factors can facilitate early diagnosis, and reduce subsequent complications.

CONCLUSION

Neonatal jaundice should be considered as the main policy in all health care settings of the country. Therefore, identification of factors affecting the incidence of jaundice can be effective in preventing susceptible predisposing factors in newborns and high-risk mothers.

Hyperthyroxinemia at birth: a cause of idiopathic neonatal hyperbilirubinemia?

BACKGROUND

Some neonates develop idiopathic hyperbilirubinemia (INHB) requiring phototherapy, yet with no identifiable causes. We searched for an association between abnormal thyroid levels after birth and INHB.

METHODS

Of 5188 neonates, 1681 (32.4%) were excluded due to one or more risk factors for hyperbilirubinemia. Total thyroxine (TT4) and thyroid stimulating hormone values were sampled routinely at 40-48 hours of age and measured in the National Newborn Screening Program.

RESULTS

Of the 3507 neonates without known causes for hyperbilirubinemia, 61 (1.7%) developed INHB and received phototherapy. Univariate analyses found no significant association between mode of delivery and INHB (vacuum-delivered neonates were a priori excluded). Nonetheless, in cesarean-delivered (CD) neonates, two variables had significant association with INHB: TT4 ≥ 13 µg/dL and birth at 38-38.6 weeks. In vaginally delivered (VD) born neonates, INHB was associated with weight loss > 7.5% up to 48 hours of age. Multivariate logistic regression analysis showed a strong effect of mode of delivery on possible significant association with INHB. In CD neonates, such variables included: TT4 ≥ 13 µg/dL [P = 0.025, odds ratio (OR) 5.49, 95% confidence interval (CI) 1.23-24.4] and birth at 38-38.6 weeks (P = 0.023, OR 3.44, 95% CI 1.19-9.97). In VD neonates, weight loss > 7.5% (P = 0.019, OR 2.1, 95% CI 1.13-3.83) and 1-min Apgar score < 9 (P < 0.001, OR 3.8, 95% CI 1.83-7.9), but not TT4, showed such an association.

CONCLUSIONS

INHB was significantly associated with birth on 38-38.6 week and TT4 (≥ 13 µg/dL) in CD neonates, and with a weight loss > 7.5% in VD neonates. We herein highlight some acknowledged risk factors for neonatal hyperbilirubinemia, and thus minimize the rate of INHB.

Umbilical cord blood acid-base analysis and the development of significant hyperbilirubinemia in near-term and term newborns: a cohort study

BACKGROUND

The recognition, follow-up, and early treatment of neonatal jaundice has become more difficult, since the earlier discharge of newborns from hospitals has become common practice. Since intrapartum hypoxic stress has been pointed as predisposing factor for the occurrence of hyperbilirubinemia risk, we tested the association with the cord blood acid-base index tests.

METHODS

A cohort of healthy term and near-term newborns underwent umbilical cord hemogasanalysis at birth and capillary heel total serum bilirubin (TSB) pre-discharge, scheduled at 36 h of life, to define the risk of significant hyperbilirubinemia, defined as >9 mg/dL TSB level, ≥ 75th percentile on nomogram of Bhutani et al.

RESULTS

It was found that among 537 studied neonates, 133 (24.8%) had pre-discharge TSB levels of >9 mg/dL. When the cord blood gas analysis index tests were compared, their acidemia levels were significantly higher than those of neonates with normal TSB levels: HCO₃^- (20.71 ± 2.37 vs. 21.29 ± 2.25 mEq/L, p < 0.010), base deficit (-3.52 ± 3.188 vs. -2.68 ± 3.266 mEq/L, p < 0.010), and lactacidemia (3.84 ± 1.864 vs. 3.39 ± 1.737 mEq/L, p < 0.012), respectively. However, logistic regression analysis showed that base deficit was the strongest index of the pre-discharge hyperbilirubinemia risk (OR, 95% CI 0.593; 0.411-0.856), and the hyperbilirubinemia risk increased by 40% with the decrease of 1 mEq/L of base deficit.

CONCLUSIONS

Umbilical cord blood acidemia and lactacidemia are significant indexes of adaptive mechanisms at birth. The base deficit provides the strongest association with future development of high bilirubin on an hour specific bilirubin nomogram generating risk stratification score in term and near-term neonates.

Reliability of transcutaneous bilirubinometry from shielded skin in neonates receiving phototherapy: a prospective cohort study

OBJECTIVE

To determine the agreement between transcutaneous bilirubin (TcB) measured from shielded skin and serum total bilirubin (STB) in infants (34 to 41 weeks of gestation) with hyperbilirubinemia receiving phototherapy (PT).

STUDY DESIGN

In this prospective cohort study, we shielded a small area of skin on sternum using a commercial photo-opaque patch (BilEclipseTM, Philips Respironics, Murrysville, PA, USA). The TcB from the shielded skin (TcBs) and STB were measured at four time points-before initiation, 12 and 24 h during and once after (12 h) cessation of PT. TcB was measured using multiwavelength transcutaneous bilirubinometer (BiliChek, Philips Children's Medical Ventures, Monroeville, PA, USA). The STB was measured in triplicate by spectrophotometry (Apel BR 5100, APEL, Japan). Bland and Altman plots were drawn to determine agreement between the TcBs and STB.

RESULTS

The gestation and birth weight of enrolled neonates were 37.0 (1.0) weeks and 2750 (458) g, respectively. The age at initiation and duration of PT were 75 (27 to 312) and 25.3 (4.4) h, respectively. Bland and Altman plot showed poor agreement between TcBs and STB at all time points. The gradient (median, range) between TcBs and STB at 0, 12, 24 h and 12 h after cessation of PT were -0.2 (-4.9 to 3.5), 1.4 (-4.7 to 4.0), 1.5 (-3.8 to 9.4) and 2 (-2.9 to 5.8) mg dl^-1. The proportions of TcBs values outside ±1.5 mg dl^-1 of STB ranged from 47 to 64% at four time points.

CONCLUSION

TcBs does not appear to be reliable for estimating serum bilirubin in late preterm and term neonates receiving PT.

Predicting Nonhemolytic Neonatal Hyperbilirubinemia

BACKGROUND

Before hospital discharge, newborn infants should be assessed for the risk of excessive hyperbilirubinemia. We determined maternal and obstetric risk factors for hyperbilirubinemia in infants born at term (gestational age ≥37 weeks) to form an individualized risk assessment tool for clinical use.

METHODS

This was a population-based study with data from the Swedish Medical Birth Register from 1999 to 2012, including 1,261,948 singleton infants. Outcome was defined as infants diagnosed with hyperbilirubinemia (N = 23,711), excluding all cases of hemolytic (immune-mediated or other specified hemolytic) diseases of the newborn.

RESULTS

Risk factors with an adjusted odds ratio (aOR) for neonatal hyperbilirubinemia of ≥1.5 (medium-sized effect or more) were gestational age 37 to 38 weeks (aOR = 2.83), failed vacuum extraction (aOR = 2.79), vacuum extraction (aOR = 2.22), Asian mother (aOR = 2.09), primipara (aOR = 2.06), large-for-gestational-age infant (aOR = 1.84), obese mother (aOR = 1.83), and small-for-gestational-age infant (aOR = 1.66). Planned cesarean delivery (CD) was associated with a reduced risk (aOR = 0.45). Without any of these risk factors (normal birth weight infant delivered vaginally at 39 to 41 weeks' gestation by a non-Asian, nonobese, multiparous mother) the rate of nonhemolytic neonatal hyperbilirubinemia was 0.7%. In relation to the combined load of different risk factors, rates of neonatal hyperbilirubinemia ranged from 0.2% to 25%.

CONCLUSIONS

Collection of a few easily available maternal and obstetric risk factors predicts >100-fold variation in the incidence of neonatal hyperbilirubinemia. The information provided herein enables individualized risk prediction with interactions between different risk factors taken into account.

A Model for Predicting Significant Hyperbilirubinemia in Neonates From China

OBJECTIVES

To develop and validate a predischarge risk stratification model by using transcutaneous bilirubin (TcB) values and clinical factors to predict significant postdischarge hyperbilirubinemia in healthy term and late preterm Chinese neonates.

METHODS

In a prospective cohort study, 8215 healthy term and late preterm neonates in 8 hospitals in China underwent TcB measurement at <168 hours of age. TcB percentiles were calculated and used to develop an hour-specific nomogram, and 9 empirically weighted items were used to derive a prediction model. A risk stratification model was developed by combining the TcB nomogram with clinical risk scores to predict significant hyperbilirubinemia, defined as a postdischarge bilirubin level that exceeded the hour-specific recommended threshold value for phototherapy. Data from another 13,157 neonates were used to validate the model.

RESULTS

A TcB nomogram for every 12 hours of the studied interval was constructed from the development set. Gestational age, male gender, history of previous neonate who received phototherapy, bruising, feeding mode, weight loss, and early discharge were predictors of postdischarge significant hyperbilirubinemia. The combination of the TcB nomogram and clinical risk score provided the best prediction of significant hyperbilirubinemia with an area under the curve of 0.95 (95% confidence interval: 0.94-0.95) in the development data set and 0.94 (95% confidence interval: 0.93-0.94) in the validation data set. A risk stratification model with 6 distinct risk levels was developed and validated.

CONCLUSIONS

A risk classification model, combining discharge transcutaneous bilirubin values and clinical risk factors, separated term and late preterm Chinese neonates into 6 risk classes for the timely follow-up of postdischarge hyperbilirubinemia detection.

Bilirubin production and hour-specific bilirubin levels

OBJECTIVE

We assessed the relative contributions of increased bilirubin production (indexed by end-tidal carbon monoxide (CO) concentrations, corrected for ambient CO (ETCOc)) to hour-specific total bilirubin (TB) levels in healthy late preterm and term newborns.

STUDY DESIGN

Post hoc analyses of concurrent ETCOc and TB (at 30±6 h of age) and follow-up TB levels at age 96±12 h and up to 168 h after birth were performed in a cohort of 641 term and late preterm infants.

RESULTS

Increased bilirubin production (hour-specific ETCOc ⩾1.7 p.p.m. at age 30±6 h) was noted in ~80%, 42% and 32% of infants in the high-, intermediate- and low-risk TB zones, respectively. One infant with TB <40th percentile and ETCOc <1.7 p.p.m. developed TB ⩾95th percentile at age 168 h, probably due to decreased bilirubin elimination.

CONCLUSIONS

Infants in the high-risk quartile of the hour-specific bilirubin nomogram have a higher mean bilirubin production. Infants with TB levels ⩾95th percentile without increased bilirubin production have impaired bilirubin elimination.

Association of neonatal hyperbilirubinemia in breast-fed infants with UGT1A1 or SLCOs polymorphisms

Neonates have physiologically increased bilirubin production and immature bilirubin metabolism, and present hyperbilirubinemia in association with genetic and or epigenetic factors. We previously reported that maximal body weight loss (inadequate feeding) is an independent risk factor for the development of hyperbilirubinemia in breast-fed Japanese neonates, and the UGT1A1 211G>A genotype becomes a risk factor under conditions of inadequate feeding. We extended the study to the association of other genetic factors, the UGT1A1 (TA)7 and solute-carrier organic anion transporters (SLCOs) polymorphisms with neonatal hyperbilirubinemia. We enrolled 401 full-term Japanese infants who were exclusively breastfeeding and classified them into two groups based on the degree of maximal body weight loss. We analyzed the clinical characteristics and UGT1A1 and SLCOs genotypes. Statistical analysis revealed that maximal body weight loss is the only independent risk factor for the development of neonatal hyperbilirubinemia. UGT1A1, SLCO1B1 and SLCO1B3 polymorphisms become risk factors in neonates showing 10% or greater body weight loss during the neonatal period. Inadequate feeding may increase the bilirubin burden and cause apparent hyperbilirubinemia in neonates, who have a polymorphic change in the genes involved in the transport and/or metabolism of bilirubin.

Bilirubin nomograms for identification of neonatal hyperbilirubinemia in healthy term and late-preterm infants: a systematic review and meta-analysis

BACKGROUND

Hyperbilirubinemia occurs in most healthy term and late-preterm infants, and must be monitored to identify those who might develop severe hyperbilirubinemia. Total serum bilirubin (TSB) or transcutaneous bilirubin (TcB) nomograms have been developed and validated to identify neonatal hyperbilirubinemia. This study aimed to review previously published studies and compare the TcB nomograms with the TSB nomogram, and to determine if the former has the same predictive value for significant hyperbilirubinemia as TSB nomogram does.

METHODS

A predefined search strategy and inclusion criteria were set up. We selected studies assessing the predictive ability of TSB/TcB nomograms to identify significant hyperbilirubinemia in healthy term and late-preterm infants. Two independent reviewers assessed the quality and extracted the data from the included studies. Meta-Disc 1.4 analysis software was used to calculate the pooled sensitivity, specificity, and positive likelihood ratio of TcB/TSB nomograms. A pooled summary of the receiver operating characteristic of the TcB/TSB nomograms was created.

RESULTS

After screening 187 publications from electronic database searches and reference lists of eligible articles, we included 14 studies in the systematic review and meta-analysis. Eleven studies were of medium methodological quality. The remaining three studies were of low methodological quality. Seven studies evaluated the TcB nomograms, and seven studies assessed TSB nomograms. There were no differences between the predictive abilities of the TSB and TcB nomograms (the pooled area under curve was 0.819 vs. 0.817).

CONCLUSIONS

This study showed that TcB nomograms had the same predictive value as TSB nomograms, both of which could be used to identify subsequent significant hyperbilirubinemia. But this result should be interpreted cautiously because some methodological limitations of these included studies were identified in this review.

Lipid peroxidation, DNA damage and total antioxidant status in neonatal hyperbilirubinemia

OBJECTIVE

Lipid peroxidation, DNA damage and total antioxidant status (TAS) were assessed in neonates with unconjugated hyperbilirubinemia (UCH).

STUDY DESIGN

Plasma malondialdehyde (MDA), 8-hydroxy-2-deoxy-guanosine (8-OH-dG) and TAS levels were compared between 64 term newborns with idiopathic UCH and 30 age-matched healthy controls.

RESULT

Compared with controls, an overall increase in mean plasma MDA and 8-OH-dG levels and a decrease in TAS level were noted in the UCH group. Within the UCH group, mean plasma MDA level was found to be low in infants with lower bilirubin levels, but a progressive increase was documented above the bilirubin level of 20 mg dl(-1). A significant increase in 8-OH-dG level was documented even at lower bilirubin levels, and a decrease i plasma TAS level was found at bilirubin levels above 16 mg dl(-1). MDA and 8-OH-dG levels were significantly higher, whereas TAS level was significantly lower in five neonates who developed features of acute bilirubin encephalopathy compared with those with normal outcome. Alteration of MDA, 8-OH-dG and TAS levels showed high predictive accuracy for poor outcome.

CONCLUSION

Moderate-to-severe UCH was associated with higher oxidative stress and lower antioxidant defense. Alteration of oxidative stress parameters may be utilized as early predictors for poor outcome. High DNA damage even at lower bilirubin levels suggests possible genotoxic effect of bilirubin in UCH.

Validation of transcutaneous bilirubin nomogram for identifying neonatal hyperbilirubinemia in healthy Chinese term and late-preterm infants: a multicenter study

OBJECTIVE

to prospectively validate a previously constructed transcutaneous bilirubin (TcB) nomogram for identifying severe hyperbilirubinemia in healthy Chinese term and late-preterm infants.

METHODS

this was a multicenter study that included 9,174 healthy term and late-preterm infants in eight hospitals of China. TcB measurements were performed using a JM-103 bilirubinometer. TcB values were plotted on a previously developed TcB nomogram, to identify the predictive ability for subsequent significant hyperbilirubinemia.

RESULTS

in the present study, 972 neonates (10.6%) developed significant hyperbilirubinemia. The 40(th) percentile of the nomogram could identify all neonates who were at risk of significant hyperbilirubinemia, but with a low positive predictive value (PPV) (18.9%). Of the 453 neonates above the 95(th) percentile, 275 subsequently developed significant hyperbilirubinemia, with a high PPV (60.7%), but with low sensitivity (28.3%). The 75(th) percentile was highly specific (81.9%) and moderately sensitive (79.8%). The area under the curve (AUC) for the TcB nomogram was 0.875.

CONCLUSIONS

this study validated the previously developed TcB nomogram, which could be used to predict subsequent significant hyperbilirubinemia in healthy Chinese term and late-preterm infants. However, combining TcB nomogram and clinical risk factors could improve the predictive accuracy for severe hyperbilirubinemia, which was not assessed in the study. Further studies are necessary to confirm this combination.

Identifying term breast-fed infants at risk of significant hyperbilirubinemia

BACKGROUND

The aim of this study was to establish a model to identify term breast-fed infants who are at risk of developing significant neonatal hyperbilirubinemia.

METHODS

A prospective study was designed to investigate the effects of birth weight, mode of delivery, cephalohematoma, glucose-6-phosphate dehydrogenase (G6PD) deficiency, predischarge total serum bilirubin, variant uridine 5'diphospho-glucuronosyltransferase 1A1 (UGT1A1) gene, and hepatic solute carrier organic anion transporter 1B1 (SLCO1B1) gene on significant hyperbilirubinemia in term breast-fed neonates. Significant hyperbilirubinemia was defined as a bilirubin level exceeding the hour-specific phototherapy treatment threshold recommended by the American Academy of Pediatrics in 2004.

RESULTS

Of 240 exclusively breast-fed term neonates, 26 (10.8%) had significant hyperbilirubinemia. The predischarge total serum bilirubin on the third day (odds ratio (OR) = 2.63; 95% confidence interval (CI): 1.87-3.70; P < 0.001) and the variant UGT1A1 gene at nucleotide 211 (OR = 5.00; 95% CI: 1.08-23.03; P < 0.05) were significant risk factors. The area under the receiver operating characteristic (ROC) curve of the predictive probability was 0.964 (95% CI: 0.932-0.984; P < 0.0001).

CONCLUSION

Combining the total serum bilirubin on the third day and the variant UGT1A1 gene at nucleotide 211 can predict hyperbilirubinemia well in term breast-fed infants.

Should we screen newborns for glucose-6-phosphate dehydrogenase deficiency in the United States?

Glucose-6-phosphate dehydrogenase (G6PD) deficiency, a common X-linked enzymopathy can lead to severe hyperbilirubinemia, acute bilirubin encephalopathy and kernicterus in the United States. Neonatal testing for G6PD deficiency is not yet routine and the American Academy of Pediatrics recommends testing only in jaundiced newborns who are receiving phototherapy whose family history, ethnicity, or geographic origin suggest risk for the condition, or for infants whose response to phototherapy is poor. Screening tests for G6PD deficiency are available, are suitable for use in newborns and have been used in birth hospitals. However, US birth hospitals experience is limited and no national consensus has emerged regarding the need for newborn G6PD testing, its effectiveness or the best approach. Our review of current state of G6PD deficiency screening highlights research gaps and informs specific operational challenges to implement universal newborn G6PD testing concurrent to bilirubin screening in the United States.

Model to predict hyperbilirubinemia in healthy term and near-term newborns with exclusive breast feeding

BACKGROUND

The aim of this study was to identify high-risk newborns who will subsequently develop significant hyperbilirubinemia Days 4 to 10 of life by using the clinical data from the first three days of life.

METHODS

We retrospectively collected exclusively breastfeeding healthy term and near-term newborns born in our nursery between May 1, 2002, to June 30, 2005. Clinical data, including serum bilirubin were collected and the significant predictors were identified. Bilirubin level ≥15mg/dL during Days 4 to 10 of life was defined as significant hyperbilirubinemia. A prediction model to predict subsequent hyperbilirubinemia was established. This model was externally validated in another group of newborns who were enrolled by the same criteria to test its discrimination capability.

RESULTS

Totally, 1979 neonates were collected and 1208 cases were excluded by our exclusion criteria. Finally, 771 newborns were enrolled and 182 (23.6%) cases developed significant hyperbilirubinemia during Days 4 to 10 of life. In the logistic regression analysis, gestational age, maximal body weight loss percentage, and peak bilirubin level during the first 72 hours of life were significantly associated with subsequent hyperbilirubinemia. A prediction model was derived with the area under receiver operating characteristic (AUROC) curve of 0.788. Model validation in the separate study (N = 209) showed similar discrimination capability (AUROC = 0.8340).

CONCLUSION

Gestational age, maximal body weight loss percentage, and peak serum bilirubin level during the first 3 days of life have highest predictive value of subsequent significant hyperbilirubinemia. We provide a good model to predict the risk of subsequent significant hyperbilirubinemia.

Predischarge non-invasive risk assessment for prediction of significant hyperbilirubinemia in term and late preterm neonates

OBJECTIVE

To evaluate efficacy of predischarge transcutaneous bilirubin (TcB) measurement and clinical risk assessment in predicting hyperbilirubinemia needing treatment.

STUDY DESIGN

A diagnostic test was performed in a prospective cohort study conducted at a teaching hospital in North India. Subjects included healthy neonates with a gestation period of ≥35 weeks or birth weight ≥2000 g. Maternal, neonatal and delivery risk factors for hyperbilirubinemia were prospectively collected. TcB was measured in all enrolled neonates at 24±6, 72 to 96 and 96 to 144 h of postnatal age and when indicated clinically. Neonates were followed up during hospital stay and after discharge till completion of the 7th postnatal day. The key outcome was significant hyperbilirubinemia defined as need of phototherapy on the basis of modified American Academy of Pediatrics guidelines. In neonates born at ≥38 weeks of gestation and in neonates born at ≤37 completed weeks of gestation, middle line and lower line of phototherapy thresholds were used to initiate phototherapy, respectively. Variables observed to be significantly associated with significant hyperbilirubinemia on multivariate analysis were used for construction of a clinical risk assessment tool. Predictive ability of the risk assessment tool was assessed by calculating sensitivity, specificity, positive predictive value and negative predictive value, by plotting receiver-operating characteristics curve and calculating c-statistic.

RESULT

A total of 997 neonates (birth weight: 2627±536 g, gestation: 37.8±1.5 weeks) were enrolled in the study, of which 931 completed follow-up. Among enrolled neonates, 344 (34.5%) were low birth weight. Overall, a total of 199 (20%) neonates developed significant hyperbilirubinemia. On stepwise logistic regression analysis, predischarge TcB percentile and gestation were significantly found to be associated with significant hyperbilirubinemia. A risk assessment graph was constructed to predict subsequent development of significant hyperbilirubinemia. Area under curve for this risk assessment strategy was 0.75.

CONCLUSION

A risk assessment graphical tool consisting of TcB and gestation accurately predicted subsequent need of phototherapy. Further studies are needed to validate performance of this risk assessment tool.

Impact of a transcutaneous bilirubinometry program on resource utilization and severe hyperbilirubinemia

OBJECTIVES

Our goal was to assess the impact of programmatic and coordinated use of transcutaneous bilirubinometry (TcB) on the incidence of severe neonatal hyperbilirubinemia and measures of laboratory, hospital, and nursing resource utilization.

METHODS

We compared the neonatal hyperbilirubinemia-related outcomes of 14 796 prospectively enrolled healthy infants ≥35 weeks gestation offered routine TcB measurements in both hospital and community settings by using locally validated nomograms relative to a historical cohort of 14 112 infants assessed by visual inspection alone.

RESULTS

There was a 54.9% reduction (odds ratio [OR]: 2.219 [95% confidence interval (CI): 1.543-3.193]; P < .0001) in the incidence of severe total serum bilirubin values (≥342 µmol/L; ≥20 mg/dL) after implementation of routine TcB measurements. TcB implementation was associated with reductions in the overall incidence of total serum bilirubin draws (134.4 vs 103.6 draws per 1000 live births, OR: 1.332 [95% CI: 1.226-1.446]; P < .0001) and overall phototherapy rate (5.27% vs 4.30%, OR: 1.241 [95% CI: 1.122-1.374]; P < .0001), a reduced age at readmission for phototherapy (104.3 ± 52.1 vs 88.9 ± 70.5 hours, P < .005), and duration of phototherapy readmission (24.8 ± 13.6 vs 23.2 ± 9.8 hours, P < .05). There were earlier (P < .01) and more frequent contacts with public health nurses (1.33 vs 1.66, P < .01) after introduction of the TcB program.

CONCLUSIONS

Integration of routine hospital and community TcB screening within a comprehensive public health nurse newborn follow-up program is associated with significant improvements in resource utilization and patient safety.

Risk of hyperbilirubinemia in breast-fed infants

OBJECTIVE

To investigate the risk factors for hyperbilirubinemia in infants who are exclusively breast-fed.

STUDY DESIGN

A prospective study was conducted to investigate the effects of birth body weight, sex, mode of delivery, glucose-6-phosphate dehydrogenase (G6PD) deficiency, variant UDP-glucuronosyltransferase 1A1 (UGT1A1) gene, and hepatic solute carrier organic anion transporter 1B1 (SLCO1B1) gene on hyperbilirubinemia in neonates who were breast-fed. Hyperbilirubinemia was diagnosed when a full term neonate had a bilirubin level ≧15.0 mg/dL (256.5 μM) in serum at 3 days old. The polymerase chain reaction-restriction fragment length polymorphism method was used as a means of detecting the known variant sites in the UGT1A1 and SLCO1B1 gene.

RESULTS

Of 252 infants born at term who were exclusively breast-fed, 59 (23.4%) had hyperbilirubinemia. The significant risk factors were a variant nucleotide 211 in UGT1A1 (2.48; 95% CI, 1.29 to 4.76; P = .006), G6PD deficiency (12.24; 95% CI, 1.08 to 138.62; P < .05), and vaginal delivery (3.55; 95% CI, 1.64 to 7.66; P < .001).

CONCLUSION

Breast-fed neonates who are 211 variants in the UGT1A1, G6PD deficiency, and vaginal delivery are at high-risk for hyperbilirubinemia.

A global need for affordable neonatal jaundice technologies

Globally, health care providers worldwide recognize that severe neonatal jaundice is a "silent" cause of significant neonatal morbidity and mortality. Untreated neonatal jaundice can lead to death in the neonatal period and to kernicterus, a major cause of neurologic disability (choreo-athetoid cerebral palsy, deafness, language difficulty) in children who survive this largely preventable neonatal tragedy. Appropriate technologies are urgently needed. These include tools to promote and enhance visual assessment of the degree of jaundice, such as simpler transcutaneous bilirubin measurements and readily available serum bilirubin measurements that could be incorporated into routine treatment and follow-up. Widespread screening for glucose-6-phoshate dehydrogenase deficiency is needed because this is often a major cause of neonatal jaundice and kernicterus worldwide. Recognition and treatment of Rh hemolytic disease, another known preventable cause of kernicterus, is critical. In addition, effective phototherapy is crucial if we are to make kernicterus a "never-event." Finally it is essential that we conduct appropriate population-based studies to accurately elucidate the magnitude of the problem. However, knowledge alone is not sufficient. If we are to implement these and other programs and technologies to relegate severe neonatal jaundice and its sequelae to the history books, screening and interventions must be low cost and technologically appropriate for low and middle income nations.

UGT1A1 sequence variants and bilirubin levels in early postnatal life: a quantitative approach

Background

Fundamental to definitively identifying neonates at risk of developing significant hyperbilirubinemia is a better understanding of the genetic factors associated with early bilirubin rise. Previous genetic studies have focused on the UGT1A1 gene, associating common variation in the coding or promoter regions with qualitative assessments of bilirubin (i.e. significantly elevated or not). These studies have had conflicting results and limited success. We chose to approach the problem by focusing on the quantitative (absolute) change in bilirubin levels early in post-natal life. We apply this approach to the UGT1A1 gene - exploring the contribution of both rare and common variants to early bilirubin changes.

Methods

We sequenced the exons, PBREM, 5'-, and 3'- regions of the UGT1A1 gene in 80 otherwise healthy term neonates who had repeat bilirubin levels measured within the first five days of life.

Results

Three novel coding variants were observed, but there was no clear relationship between rare coding variants and bilirubin rise. Adjusted linear regression models fit to evaluate the relationship between changing bilirubin levels and common UGT1A1variants found that among 39 neonates whose bilirubin was resampled within 33 hours, individuals homozygous for the mutant allele of a 3'UTR SNP had significantly smaller changes in bilirubin (P = 0.003) than individuals carrying the wild-type allele.

Conclusions

Collectively, rare UGT1A1 coding variants do not appear to play a prominent role in determining early bilirubin levels; however common variants in the 3' UTR of UGT1A1 may modulate the early bilirubin rise. A quantitative approach to evaluating early bilirubin kinetics provides a more robust framework in which to better understand the genetics of neonatal hyperbilirubinemia.

Universal bilirubin screening for severe neonatal hyperbilirubinemia

To reduce the incidence of severe neonatal hyperbilirubinemia affecting newborns with jaundice in the United States and to prevent kernicterus, there is a need to implement proven prevention strategies for severe neonatal hyperbilirubinemia as recommended in the 2004 American Academy of Pediatrics Guidelines for newborns >35 weeks gestational age. The purpose of universal predischarge bilirubin screening is to identify infants with bilirubin levels >75th percentile for age in hours and track those with rapid rates of bilirubin rise (>0.2 mg per 100 ml per h). Early identification has been reported to predict severe hyperbilirubinemia and allow for evidence-based targeted interventions. A systems approach is likely to reduce the preventable causes of acute bilirubin encephalopathy. To do so, highest priority should be given to (i) designating extreme hyperbilirubinemia (total serum bilirubin >427 μmol l(-1) or >25 mg per 100 ml) as a reportable condition by laboratories and health-care providers through public health mandates; (ii) implementation of Joint Commission's Sentinel Report for kernicterus; (iii) nursing outreach to communities for education of prospective parents; (iv) development of clinical pathways to monitor, evaluate and track infants with extreme hyperbilirubinemia; and (v) societal awareness. These efforts should be monitored by a state and national surveillance system in order to critically improve the timeliness and completeness of notifications and to allow evaluation and interventions at the policy and individual family level.

Transcutaneous bilirubin levels in healthy term and late preterm Indian neonates

OBJECTIVE

To provide normative data for transcutaneous bilirubin (TcB) measurements in healthy term and late-preterm Indian neonates during first 72 h of age using a multiwavelength reflectance transcutaneous bilimeter.

METHODS

TcB measurements were performed in healthy neonates (gestation 35 wk), in a well-baby ward, using a multiwavelength transcutaneous bilimeter (BiliCheck, SpectRx Inc, Norcross, GA). Age-specific percentiles values for each 6-h epoch starting at 0 h of age were calculated and an age-specific TcB nomogram was developed using different percentile values. Diagnostic ability of each percentile curve for prediction of hyperbilirubinemia, defined as requirement of phototherapy, was calculated.

RESULTS

We performed 925 TcB measurements on 625 healthy newborn infants (gestation: 35 to 41 wk; age: 0 to 72 h; mean birth weight: 2808+/-437 g). TcB increased in a linear manner with maximum rate of rise observed during first 24 h of age (50th percentile: 0.22 mg/dL/h). 50th percentile curve of age-specific TcB nomogram had high negative predictive value (99.8%) and acceptable positive predictive value (16.4%) for prediction of hyperbilirubinemia.

CONCLUSION

We provided age-specific nomogram of TcB for first 72 h of age in healthy term and late-preterm Indian neonates. Percentile curves and rate of rise in TcB may help in identification of neonates at low-risk of development of hyperbilirubinemia facilitating their safer discharge from the hospital. Diagnostic utility of this nomogram for predicting hyperbilirubinemia needs to be tested in a separate validation cohort.

False-negative results of pre-discharge neonatal bilirubin screening to predict severe hyperbilirubinemia: a need for caution

Routine bilirubin screening prior to newborn hospital discharge, using an hour-specific bilirubin nomogram, has been advocated to assess risk for subsequent severe hyperbilirubinemia. However, the false-negative rate has never been adequately studied. Our objective was to determine false-negative results of pre-discharge bilirubin screening. After routine pre-discharge, bilirubin screening was in place for over 4 years, we performed a retrospective chart review to identify infants readmitted for total bilirubin levels > 17 mg/dl (>290.7 micromol/l). We documented each infant's pre-discharge bilirubin level, risk-zone assignment by nomogram, the presence or absence of risk factors for severe hyperbilirubinemia, co-morbidities upon readmission, treatment received, and ultimate disposition. Readmitted infants whose pre-discharge bilirubin was in the low-risk (<40th percentile) and low-intermediate (40-75th percentile) risk zones of the nomogram, were considered false-negatives. Of the 6,220 infants discharged from the newborn nursery during the 51-month study period, 28 (0.45%) were readmitted for treatment of serum bilirubin levels > 17 mg/dl (>290.7 micromol/l). All received phototherapy and none required exchange transfusion. Pre-discharge bilirubin values were <40th percentile (low-risk zone) in one infant (3.6%), and between 40-75th percentiles (low-intermediate risk zone) in twelve infants (43%). Risk factors for the development of severe hyperbilirubinemia were present in 27 (96%) readmitted infants. In conclusion, nearly half of readmitted infants had pre-discharge bilirubin values in zones considered at lower risk. The use of pre-discharge bilirubin screening alone to assign future risk for severe hyperbilirubinemia may provide false reassurance. Rigorous research is required to determine the test characteristics of pre-discharge bilirubin screening before widespread acceptance and implementation. Universal early post-discharge follow-up should remain the cornerstone of preventing severe hyperbilirubinemia.

Systematic review of screening for bilirubin encephalopathy in neonates

CONTEXT

Severe neonatal hyperbilirubinemia is associated with chronic bilirubin encephalopathy (kernicterus).

OBJECTIVE

To systematically review the effectiveness of specific screening modalities to prevent neonatal bilirubin encephalopathy.

METHODS

We identified studies through Medline searches, perusing reference lists and by consulting with US Preventive Services Task Force lead experts. We included English-language publications evaluating the effects of screening for bilirubin encephalopathy using early total serum bilirubin (TSB), transcutaneous bilirubin (TcB) measurements, or risk scores. Severe hyperbilirubinemia was used as a surrogate for possible chronic bilirubin encephalopathy, because no studies directly evaluated the latter as an outcome. We calculated the sensitivity and specificity of early TSB, TcB measurements, or risk scores in detecting hyperbilirubinemia.

RESULTS

Ten publications (11 studies) were eligible. Seven (2 prospective) studies evaluated the ability of risk factors (n = 3), early TSB (n = 3), TcB (n = 2), or combinations of risk factors and early TSB (n = 1) to predict hyperbilirubinemia (typically TSB > 95th hour-specific percentile 24 hours to 30 days postpartum). Screening had good ability to detect hyperbilirubinemia: reported area-under-the-curve values ranged between 0.69 and 0.84, and reported sensitivities and specificities suggested similar diagnostic ability. Indirect evidence from 3 descriptive uncontrolled studies suggests favorable associations between initiation of screening and decrease in hyperbilirubinemia rates, and rates of treatment or readmissions for hyperbilirubinemia compared with the baseline of no screening. No study assessed harms of screening.

CONCLUSIONS

Effects of screening on the rates of bilirubin encephalopathy are unknown. Although screening can predict hyperbilirubinemia, there is no robust evidence to suggest that screening is associated with favorable clinical outcomes.

Screening of infants for hyperbilirubinemia to prevent chronic bilirubin encephalopathy: US Preventive Services Task Force recommendation statement

DESCRIPTION

Recommendation on screening newborn infants, based on a recent supplemental review of a 2003 Agency for Healthcare Research and Quality evidence report on the effectiveness of various screening strategies for preventing the development of chronic bilirubin encephalopathy, performed at the request of the US Preventive Services Task Force (USPSTF). This topic has not been previously considered by the USPSTF.

METHODS

The USPSTF reviewed experimental and observational studies that included comparison groups. For harms associated with phototherapy, case reports or case series were also included.

CONCLUSION

The evidence is insufficient to assess the balance of benefits and harms of screening for hyperbilirubinemia to prevent chronic bilirubin encephalopathy (I statement).

Screening for severe neonatal hyperbilirubinemia

Screening for severe neonatal hyperbilirubinemia is integral to newborn care. Predischarge risk assessment relies on documentation of visual jaundice: age at onset and progression; identification of clinical risk such as late prematurity and bruising; with determination of total bilirubin (blood or transcutaneous assay) adjusted for age in hours. Along with promotion of breastfeeding, coordination between birthing hospital and medically supervised outpatient follow-up, a systems approach allows for a safer and effective means to prevent adverse effects of extreme hyperbilirubinemia.

The need for neonatal glucose-6-phosphate dehydrogenase screening: a global perspective

Glucose-6-phosphate dehydrogenase (G-6-PD) deficiency is an important cause of severe neonatal hyperbilirubinemia, and is overrepresented, even in countries with a low overall incidence of the enzyme deficiency, in the etiology of kernicterus. Neonatal screening for G-6-PD deficiency before discharge from the birth hospitalization should be instrumental in increasing parental and medical caretaker awareness of the high-risk nature of an infant, thereby effecting earlier referral of hyperbilirubinemic neonates for medical evaluation and treatment. The need for global screening, timing of screening, and the pros and cons of biochemical versus molecular DNA screening were discussed at the Newborn Jaundice and Kernicterus Meeting in Siena. The participants agreed that there was a need to expand neonatal G-6-PD screening globally and that screening results should be obtained before the infants' discharge from birth hospitalization.

Is the hour-specific bilirubin nomogram suitable for predicting hyperbilirubinemia

OBJECTIVE

To demonstrate the effectiveness of the hour-specific serum bilirubin nomogram, described by Bhutani et al, in predicting significant hyperbilirubinemia in term Turkish newborns.

METHODS

A total of 217 healthy term newborns without signs of hemolysis were enrolled. Serum bilirubin levels were obtained at discharge and whenever visible jaundice was observed. According to the percentile-based hour specific bilirubin nomogram the babies were grouped into four categories (high, high/low, intermediate or low risk zone). All babies were followed up for hyperbilirubinemia and examined between 7 to 10 days of life and a bilirubin level was obtained when jaundice was observed.

RESULTS

The mean predischarge bilirubin of cases was 9.71+/-3.4mg/dl. Thirty six patients (16.6%) received phototherapy while none of the cases had an exchange transfusion. The distribution of cases according to the high risk, intermediate, low/high, and low zones and the percentage of babies who received phototherapy were, 21(63.6%), 10(38.5%), 3(4.5%) and 2(2.2%), respectively. The risk of phototherapy decreased to 0.35 times for every increasing week of gestational age. Babies in the high intermediate and high risk zones were more likely to receive phototherapy (OR:24.5 and OR:83.6)

CONCLUSION

The hour-specific serum bilirubin nomogram described by Bhutani et al. predicted clinically significant hyperbilirubinemia in Turkish term newborns.

Erythroid apoptosis in idiopathic neonatal jaundice

OBJECTIVES

The objectives of this study were to evaluate the contribution of erythroid apoptosis to neonatal idiopathic pathologic jaundice and to determine whether a measurement of the erythroid apoptosis value at birth could predict the development of hyperbilirubinemia during the first 15 days of life.

PATIENTS AND METHODS

Three groups were defined: group 1 (n = 101), healthy newborns whose erythroid apoptosis value and serum total bilirubin levels were detected from birth to day 15; group 2 (n = 24), newborns who were hospitalized for jaundice (serum total bilirubin level: > 12.9 mg/dL) without any identifiable pathologic cause; and group 3 (control group, n = 24), healthy newborns whose serum total bilirubin levels were < or = 12.9 mg/dL. Erythroid apoptosis value was assessed by flow cytometry using an annexin-V fluorescein isothiocyanate kit.

RESULTS

In group 1, there was no correlation between the erythroid apoptosis value and serum total bilirubin levels obtained at birth and at the fourth and 15th days of life; the erythrocyte apoptosis value obtained at birth was not significantly different between the neonates whose serum total bilirubin levels were > 12.9 and < or = 12.9 mg/dL and who had prolonged and nonprolonged jaundice during follow-up. The erythroid apoptosis value differed significantly between the newborns in groups 2 and 3. There was no significant correlation between the erythroid apoptosis value and serum total bilirubin levels of the infants in groups 2 and 3.

CONCLUSIONS

The erythroid apoptosis value obtained at birth could not predict the development of hyperbilirubinemia in neonates, but it was increased significantly in jaundiced neonates whose serum total bilirubin levels were > 12.9 mg/dL. In these infants, increase in the erythroid apoptosis value may be a result of the toxic effect of bilirubin or of a protective mechanism of neonates to increase heme turnover and bilirubin production to diminish oxidative stress.