American Academy of Pediatrics Subcommittee on Hyperbilirubinemia. Management of hyperbilirubinemia in the newborn infant 35 or more weeks of gestation

A decline in the frequency of neonatal exchange transfusions and its effect on exchange-related morbidity and mortality

OBJECTIVE

Our goal was to identify trends in patient demographics and indications for and complications related to neonatal exchange transfusion over a 21-year period in a single institution using a uniform protocol for performing the procedure.

METHODS

A retrospective chart review of 107 patients who underwent 141 single- or double-volume exchange transfusions from 1986-2006 was performed. Patients were stratified into 2 groups, 1986-1995 and 1996-2006, on the basis of changes in clinical practice influenced by American Academy of Pediatrics management guidelines for hyperbilirubinemia.

RESULTS

There was a marked decline in the frequency of exchange transfusions per 1000 newborn special care unit admissions over the 21-year study period. Patient demographics and indications for exchange transfusion were similar between groups. A significantly higher proportion of patients in the second time period received intravenous immunoglobulin before exchange transfusion. There was a higher proportion of patients in the 1996-2006 group with a serious underlying condition at the time of exchange transfusion. During that same time period, a lower proportion of patients experienced an adverse event related to the exchange transfusion. Although a similar percentage of patients in both groups experienced hypocalcemia and thrombocytopenia after exchange transfusion, patients treated from 1996-2006 were significantly more likely to receive calcium replacement or platelet transfusion. No deaths were related to exchange transfusion in either time period.

CONCLUSIONS

Improvements in prenatal and postnatal care have led to a sharp decline in the number of exchange transfusions performed. This decline has not led to an increase in complications despite relative inexperience with the procedure.

Increased hemolysis from saline pre-washing RBCs or centrifugal pumps in neonatal ECMO

OBJECTIVES

Hemolysis is a significant complication of extracorporeal membrane oxygenation (ECMO), with a reported incidence of 12.2%. The aims of this study were (1) to investigate hemolysis caused by saline-washed versus unwashed RBCs, (2) to determine in vitro the effects of saline washing on erythrocyte hemolytic markers and (3) to investigate hemolysis by centrifugal versus roller pumps.

STUDY DESIGN

(1) To evaluate the effect of pre-transfusion saline-washing versus non-washing, the peak plasma-free hemoglobin (FHb) and total bilirubin in the first 3 days versus the next 4 days of ECMO were compared (2) Pre- and postsaline-washed RBCs were analyzed for K+ hemoglobin, mean corpuscular volume, FHb and hemolysis at baseline and after 4 h of storage at 4 degrees C. (3) Over 10 000 neonatal ECMO cases were retrospectively reviewed to study the effect of pump type on hemolysis.

RESULTS

(1) The washed blood group had significantly more hemolysis within the first 3 days of ECMO. (2) Immediately after saline washing, the K+ and Hb concentrations were significantly decreased compared with unwashed blood, and these differences were maintained after 4 h. The osmotic fragility of washed RBCs after 4 h of storage at 4 degrees C was significantly higher than at baseline. (3) Hemolysis was reported more often in the centrifugal than in the roller pump group.

CONCLUSIONS

(1) Using unwashed RBCs decreased hemolysis within the first 3 days of ECMO. (2) Saline washing, while decreasing the concentration of K+ in the plasma, significantly increases RBC membrane osmotic fragility. (3) Hemolysis is linked to the use of centrifugal pumps.

Preparation for discharge, maternal satisfaction, and newborn readmission for jaundice: comparing postpartum models of care

BACKGROUND

Physiological jaundice generally appears between the third and fifth days of life. The danger of hyperbilirubinemia is therefore a major challenge when postpartum hospital stays are short, and part of the responsibility for screening for signs of jaundice is assumed by the mother. The objective of this study was to identify the model of postnatal continuity of care most likely to prepare mothers for discharge, to reduce newborn readmission for jaundice, and to enhance maternal satisfaction.

METHODS

An epidemiological study was conducted in regions operating under 3 different models of postnatal continuity of care. Eligible mothers were those who had spent less than 60 hours in hospital after an uncomplicated vaginal delivery. Of this group, 70.8 percent participated in telephone interviews conducted 1 month after their deliveries (n=1,096). Newborns who had presented with signs of jaundice were identified through statements from their mothers.

RESULTS

Of the participating newborns, 45.5 percent presented with signs of jaundice, and 3.2 percent were readmitted for jaundice during the first week of life. The follow-up procedures used in regions operating under a community-based model most closely followed the recommendations of health authorities and featured a high level of mothers' satisfaction. In the region operating under a mixed hospital model, mothers reported signs of jaundice significantly more often, and postdischarge services received by mothers were less effective at allaying their fears compared with other models. Phototherapy was offered in the home only in the region operating under a mixed ambulatory model, and no readmissions for jaundice were recorded in this region.

CONCLUSIONS

An effective coordination between community-based perinatal services and hospital-linked home phototherapy in the form of an integrated network appears to be an essential condition for improved monitoring of newborns' health since it fosters a follow-up that is focused not only on jaundice but also on mothers' and newborns' needs while reducing the costs generated by newborn readmissions.

Influence of hypoxia and ischemia preconditioning on bilirubin damage to astrocytes

Hypoxia-ischemia in the perinatal period is a common cause of neurologic disability in children and is often associated with neonatal morbidity and mortality. Another frequent condition of the newborn is hyperbilirubinemia and it is well known that deposition of unconjugated bilirubin (UCB) in the central nervous system can damage nerve cells and cause encephalopathy. Interestingly, some studies report the onset of cerebral hypoxia-ischemia as a risk factor for UCB encephalopathy, since that condition often precedes neonatal hyperbilirubinemia. However, the cellular mechanisms triggered by hypoxia-ischemia that may enforce UCB deleterious effects are not well elucidated. Therefore, we designed this study to investigate whether hypoxia (HP) or combined oxygen-glucose deprivation (OGD) followed by reoxygenation, modifies glial cell susceptibility to UCB injury. Thus, cultured astrocytes were exposed to HP or OGD for 4 h and returned to normoxic conditions for another 12 h prior to incubation with UCB for 4 h. HP and OGD effects in UCB toxicity were compared to normoxic conditions. Our results demonstrate that HP and OGD preconditioning increase the vulnerability of glial cells to UCB damage by enhancing some of the deleterious effects of UCB, namely cell death by both apoptosis and necrosis. This preconditioning also augments the UCB-induced stimulation of an inflammatory response by an effect that involves the activation of the nuclear factor kappaB activation. These findings provide a novel basis for the increased risk of brain damage in jaundiced newborns that were previously exposed to hypoxia or ischemia during the perinatal period, namely during delivery.

Guidelines on the Use of Intravenous Immune Globulin for Hematologic Conditions

Canada's per capita use of intravenous immune globulin (IVIG) grew by approximately 115% between 1998 and 2006, making Canada one of the world's highest per capita users of IVIG. It is believed that most of this growth is attributable to off-label usage. To help ensure IVIG use is in keeping with an evidence-based approach to the practice of medicine, the National Advisory Committee on Blood and Blood Products of Canada (NAC) and Canadian Blood Services convened a panel of national experts to develop an evidence-based practice guideline on the use of IVIG for hematologic conditions. The mandate of the expert panel was to review evidence regarding use of IVIG for 18 hematologic conditions and formulate recommendations on IVIG use for each. A panel of 13 clinical experts and 1 expert in practice guideline development met to review the evidence and reach consensus on the recommendations for the use of IVIG. The primary sources used by the panel were 3 recent evidence-based reviews. Recommendations were based on interpretation of the available evidence and where evidence was lacking, consensus of expert clinical opinion. A draft of the practice guideline was circulated to hematologists in Canada for feedback. The results of this process were reviewed by the expert panel, and modifications to the draft guideline were made where appropriate. This practice guideline will provide the NAC with a basis for making recommendations to provincial and territorial health ministries regarding IVIG use management. Specific recommendations for routine use of IVIG were made for 7 conditions including acquired red cell aplasia; acquired hypogammaglobulinemia (secondary to malignancy); fetal-neonatal alloimmune thrombocytopenia; hemolytic disease of the newborn; HIV-associated thrombocytopenia; idiopathic thrombocytopenic purpura; and posttransfusion purpura. Intravenous immune globulin was not recommended for use, except under certain life-threatening circumstances, for 8 conditions including acquired hemophilia; acquired von Willebrand disease; autoimmune hemolytic anemia; autoimmune neutropenia; hemolytic transfusion reaction; hemolytic transfusion reaction associated with sickle cell disease; hemolytic uremic syndrome/thrombotic thrombocytopenic purpura; and viral-associated hemophagocytic syndrome. Intravenous immune globulin was not recommended for 2 conditions (aplastic anemia and hematopoietic stem cell transplantation) and was contraindicated for 1 condition (heparin-induced thrombocytopenia). For most hematologic conditions reviewed by the expert panel, routine use of IVIG was not recommended. Development and dissemination of evidence-based guidelines may help to facilitate appropriate use of IVIG.

Evaluation of discharge management in the prediction of hyperbilirubinemia: the Jerusalem experience

OBJECTIVE

We evaluated our program for prediction and follow-up of hyperbilirubinemia in preventing plasma total bilirubin (PTB) > or = 25 mg/dL and in limiting readmission for hyperbilirubinemia.

STUDY DESIGN

Term and near-term neonates were screened before discharge for risk factors for hyperbilirubinemia. A PTB test was performed when visible jaundice was apparent. Formal postdischarge follow-up was integrated with a possibly unique religious/cultural support system complemented by ritual circumciser (mohel) home visits and a high rate of jaundice awareness in the community.

RESULTS

During 2001-2002, 18,079 term and near-term healthy neonates were cared for in our well baby nurseries. Three hundred forty-two (1.9%) were treated with phototherapy, and 4 with exchange transfusion. Seventy-four (21.6%) of these (0.41% of total) were readmitted for hyperbilirubinemia. Forty-two percent of those readmitted had not been regarded as sufficiently jaundiced to warrant a predischarge bilirubin determination. In only 1 neonate did the PTB exceed > or = 25.0 mg/dL (0.006%). No infant had signs of bilirubin encephalopathy.

CONCLUSIONS

Our practice was successful in keeping the number of readmitted neonates low and limiting those with extreme hyperbilirubinemia to the minimum. Local customs, rituals, and practices may be successfully adapted as adjuncts in the detection and prevention of hyperbilirubinemia.

Delayed cord clamping and haemoglobin levels in infancy: a randomised controlled trial in term babies

OBJECTIVES

This study was carried out to assess whether delaying umbilical cord clamping is effective in improving the haematological status of term infants living in a malaria-endemic area, and whether this is associated with complications in infants and mothers.

METHODS

We randomly assigned women delivering term babies in Mpongwe Mission Hospital, Zambia, to delayed cord clamping (DCC, n = 46) or immediate cord clamping (controls, n = 45) and followed their infants on a bi-monthly basis until the age of 6 months. We compared the haemoglobin (Hb) change from cord values and the proportion of anaemic infants. Secondary outcomes related to infant and maternal safety.

RESULTS

Throughout the observation period infant Hb levels in both groups declined, but more rapidly in controls than in the DCC group [difference in Hb change from baseline at 4 months 1.1 g/dl, 95% confidence interval (CI) 0.2; 2.1]. By 6 months, this difference had disappeared (0.0 g/dl, 95% CI -0.9; 0.8). The odds ratio for iron deficiency anaemia in the DCC group at 4 months was 0.3 (95% CI 0.1; 1.0), but no differences were found between the groups at 6 months. No adverse events were seen in infants and mothers.

CONCLUSION

Our findings indicate that DCC could help improve the haematological status of term infants living in a malaria-endemic region at 4 months of age. However, the beneficial haematological effect disappeared by 6 months. This simple, free and safe delivery procedure might offer a strategy to reduce early infant anaemia risk, when other interventions are not yet feasible.

Randomized, controlled trial of early intravenous nutrition for prevention of neonatal jaundice in term and near-term neonates

BACKGROUND

This study was undertaken to investigate the effects of early parenteral nutrition on prevention of neonatal jaundice in term and near-term neonates who could not be enterally fed.

PATIENTS AND METHODS

Seventy-two infants were randomized into 2 groups: the early parenteral nutrition group (group 1) received 1.0 g/kg/d amino acids beginning within the first day and 1.0 g/kg/d lipid added the next day. The conventional nutrition group (group 2) started on a solution containing 10% glucose and electrolytes in the first 72 hours of life, followed by 0.5 g/kg/d amino acids and lipid. Amino acids and lipid were each increased by 0.5 g/kg/d to a maximum of 3.0 g/kg/d in both groups. Main outcome measures were energy intake; serum bilirubin levels at 24, 48, and 72 hours; need for phototherapy; and duration of phototherapy.

RESULTS

Higher energy intake was achieved after the first day in group 1. Daily serum bilirubin levels did not significantly differ between groups. Nine patients in each group required phototherapy. The initiation times of phototherapy were 92.9 hours +/- 25.5 in group 1 and 83.1 hours +/- 28.5 in group 2. Durations of phototherapy were 37.3 hours +/- 11.1 in group 1 and 52.0 hours +/- 20.7 in group 2. There were no significant differences in the requirement, initiation time, and duration of phototherapy.

CONCLUSIONS

Early parenteral nutrition has no proven benefit in terms of therapy requirement or severity and duration of neonatal jaundice compared with conventional parenteral nutrition in term and near-term infants who could not be enterally fed.

Effects of sample dilution, peroxidase concentration, and chloride ion on the measurement of unbound bilirubin in premature newborns

OBJECTIVES

To assess the effects of sample dilution, peroxidase concentration, and chloride ion (Cl(-)) on plasma unbound bilirubin (B(f)) measurements made using a commercial peroxidase methodology (UB Analyzer) in a study population of ill, premature newborns.

DESIGN AND METHODS

B(f) was measured with a UB Analyzer in 74 samples at the standard 42-fold sample dilution and compared with B(f) measured at a 2-fold sample dilution using a FloPro Analyzer. B(f) was measured at two peroxidase concentrations to determine whether the peroxidase steady state B(f) (B(fss)) measurements were significantly less than the equilibrium B(f) (B(feq)), in which case it was necessary to calculate B(feq) from the two B(fss) measurements. B(f) was also measured before and after adding 100 mmol/L Cl(-) to the UB Analyzer assay buffer.

RESULTS

B(feq) at the 42-fold dilution was nearly 10-fold less than but it correlated significantly with B(feq) at the 2-fold dilution (mean 8.2+/-5.2 nmol/L versus 73.5+/-70 nmol/L, respectively, p<0.0001; correlation r=0.6). The two UB Analyzer B(fss) measurements were significantly less than B(feq) in 42 of 74 (57%) samples, and Cl(-) increased B(feq) in 66 of 74 (89%) samples by a mean of 82+/-67%.

CONCLUSIONS

B(fss) measured by the UB Analyzer at the standard 42-fold sample dilution using assay buffer without Cl(-) and a single peroxidase concentration is significantly less than the B(feq) in undiluted plasma. Accurate B(f) measurements can be made only in minimally diluted serum or plasma.

Critical overview of the management of neonatal jaundice in the UK

AIM

To determine the current management of early neonatal jaundice in the UK and to evaluate whether the current practices are evidence based.

METHODS

A questionnaire survey was carried out among identified lead paediatricians of neonatal intensive care units.

RESULTS

The survey found markedly differing practices for the recognition, investigation and treatment of neonatal jaundice. This applies particularly to confirmation of the clinical suspicion of jaundice; use of invasive and non-invasive technologies for diagnosis; preferred wavelength and intensity of light used for treatment; and whether birth weight, gestational age and postnatal age should influence treatment.

CONCLUSION

The study found a lack of consistency in the management of jaundiced infants in the UK. The evidence-based practice currently available does not appear to have been incorporated into treatment protocols.

Apoptosis and impairment of neurite network by short exposure of immature rat cortical neurons to unconjugated bilirubin increase with cell differentiation and are additionally enhanced by an inflammatory stimulus

Nerve cell injury induced by unconjugated bilirubin (UCB) has been implicated in brain damage during severe neonatal hyperbilirubinemia, although the molecular mechanisms underlying UCB neurotoxicity are still not clarified. It has been suggested recently that there is an association between hyperbilirubinemia and long-term neurologic dysfunctions. We incubated immature neurons with UCB to evaluate the short- and long-term effects of UCB on apoptotic death and on neuritic outgrowth and ramification. We also evaluated whether mature neurons, exposed previously to UCB in an early stage of differentiation, are more sensitive to apoptosis or to neuritic breakdown when treated with inflammatory agents, such as lipopolysaccharide and tumor necrosis factor-alpha. Results show that exposure of immature neurons to UCB increased apoptosis and provoked a reduction of both neurite extension and number of nodes. These injurious effects observed in immature cells treated with UCB were increasingly perpetuated along cell differentiation, as compared to neurons incubated in the absence of UCB. In addition, neurons that were exposed to UCB when immature showed an increased susceptibility to death by apoptosis, as well as an additional decrease in neurite outgrowth when incubated with an inflammatory agent afterward. This work shows, for the first time, that UCB induces neurite changes consistent with neurodevelopment abnormalities. Furthermore, pre-exposure to UCB followed by an inflammatory stimulus leads to an enhanced susceptibility to long-term apoptosis, as well as a greater neuritic breakdown. These data support the association between neonatal hyperbilirubinemia and the later development of mental illness, such as schizophrenia.

Benefits and risks of breastfeeding

In the absence of significant, unpreventable risks, breastfeeding should be the norm for the nourishment of human infants and should, therefore, be encouraged for populations in all countries. Continued efforts of international and national agencies and healthcare professionals to aid and abet breastfeeding, reduce the risks that occur in some women during breastfeeding, provide the safest substitutes for human milk when that is necessary, and encourage further research into the posed questions should considerably improve the health of many children.

Effect of hyperbilirubinemia on intestinal permeability in healthy term newborns

We investigated the effect of serum bilirubin (SB) on intestinal permeability (IP) of healthy, term, birth weight appropriate for gestational age neonates before phototherapy. IP was measured by the dual probe (lactulose/mannitol) sugar absorption test (SAT) performed on the third day of life in 12 healthy jaundiced newborns (total bilirubin 249 +/- 39.75 micromol/L) and compared to that of 12 non-jaundiced newborns (total bilirubin 83.79 + 37.62 micromol/L) matched for sex, gestational age, birth weight and Apgar score. Jaundiced newborns have a significantly higher La/Ma ratio than non-jaundiced (0.31 +/- 0.28 vs. 0.053 +/- 0.043; p < 0.0004). A significant correlation was found between serum bilirubin level and La/Ma ratio (r = 0.56 p < 0.006).

CONCLUSION

Our study demonstrates a direct effect of UCB on gut epithelial barrier of at-term newborns in whom UCB appears to be responsible for an alteration of IP that theoretically may lead to a passage of macromolecules through the intestinal epithelium increasing the risk of sensitization.

Preventable newborn readmissions since passage of the Newborns' and Mothers' Health Protection Act

BACKGROUND

Congress passed the Newborns' and Mothers' Health Protection Act in 1996, reversing the trend of shorter newborn nursery lengths of stay. Hope existed that morbidities would lessen for this vulnerable population, but some reports indicate that the timeliness and quality of postdischarge care may have worsened in recent years.

OBJECTIVE

Our goal was to determine risk factors for the potentially preventable readmissions because of jaundice, dehydration, or feeding difficulties in the first 10 days of life in Pennsylvania since passage of the Newborns' and Mothers' Health Protection Act.

PATIENTS AND METHODS

Birth records from 407,826 newborns > or = 35 weeks' gestation from 1998 to 2002 were merged with clinical discharge records. A total of 2540 newborns rehospitalized for jaundice, dehydration, or feeding difficulties in the first 10 days of life were then compared with 5080 control infants. Predictors of readmission were identified by using multiple logistic regression analysis.

RESULTS

An unadjusted comparison of baseline characteristics revealed numerous predictors of readmission. Subsequent adjusted analysis revealed that Asian mothers, those 30 years of age or older, nonsmokers, and first-time mothers were more likely to have a readmitted newborn, as were those with diabetes and pregnancy-induced hypertension. For neonates, female gender and delivery via cesarean section were protective for readmission, whereas vacuum-assisted delivery, gestational age < 37 weeks, and nursery length of stay < 72 hours were predictors of readmission in the first 10 days of life.

CONCLUSIONS

Although readmissions for jaundice, dehydration, and feeding difficulties may be less common for some minority groups and Medicaid recipients in the era of the Newborns' and Mothers' Health Protection Act compared with nonminorities or privately insured patients, several predictors of newborn readmission have established associations with inexperienced parenting and/or breastfeeding difficulty. This is one indication that this well-intentioned legislation and current practice may not be sufficiently protecting the health of newborns and suggests that additional support for mothers and newborns during the vulnerable postdelivery period may be indicated.

Neurodevelopmental outcome of the late preterm infant

There is very limited information about the developmental outcome of the late preterm infant. The developing brain is vulnerable to injury during this very active and important stage of fetal brain development; therefore, it is important to carefully monitor the neurologic outcome of these infants. This article discusses gestational brain development and complications of late preterm birth that contribute to the overall risk of brain injury.

Hyperbilirubinemia and bilirubin toxicity in the late preterm infant

Late preterm gestation is an important risk factor for the development of severe neonatal hyperbilirubinemia and kernicterus. An exaggerated hepatic immaturity contributes to the greater prevalence, severity, and duration of neonatal jaundice in late preterm infants. Breast milk feeding is almost uniformly present and large for gestational age status, male sex, and G6PD deficiency are over-represented among that cohort of late preterm infants with kernicterus. Attention to screening measures for jaundice in the newborn nursery, the provision of lactation support, parental education, timely postdischarge follow-up, and appropriate treatment when clinically indicated should help to reduce the risk of late preterm neonates developing severe neonatal jaundice or kernicterus.

Fundamentals of phototherapy for neonatal jaundice

Phototherapy is the use of visible light for the treatment of hyperbilirubinemia in the newborn. This relatively common therapy lowers the serum bilirubin level by transforming bilirubin into water-soluble isomers that can be eliminated without conjugation in the liver. The dose of phototherapy largely determines how quickly it works; the dose, in turn, is determined by the wavelength of the light, the intensity of the light (irradiance), the distance between the light and the infant, and the body surface area exposed to the light. Commercially available phototherapy systems include those that deliver light via fluorescent bulbs, halogen quartz lamps, light-emitting diodes, and fiberoptic mattresses. Proper nursing care enhances the effectiveness of phototherapy and minimizes complications. Caregiver responsibilities include ensuring effective irradiance delivery, maximizing skin exposure, providing eye protection and eye care, carefully monitoring thermoregulation, maintaining adequate hydration, promoting elimination, and supporting parent-infant interaction.

Evaluation of a new transcutaneous bilirubinometer in Chinese newborns

OBJECTIVE

To evaluate the use of a new transcutaneous bilirubinometer (JM-103 Minolta Airshields) for detection of hyperbilirubinaemia in term or near-term healthy Chinese newborns.

METHODS

Transcutaneous bilirubin (TcB) was used to screen for severe hyperbilirubinaemia in newborn infants. Blood was taken for total serum bilirubin (TSB) measurement if the initial TcB level was higher than the 40th centile in Bhutani's nomogram. Paired TcB and TSB results were then reviewed over 6 months. The correlation as well as the mean difference between the two methods were calculated. The clinical application of TcB with Bhutani's nomogram in the prediction of severe hyperbilirubinaemia in low-risk, medium-risk and high-risk thresholds for phototherapy was also analysed.

RESULTS

997 paired TcB and TSB measurements were evaluated in term or near-term newborns. TcB was significantly correlated with TSB, with a correlation coefficient of 0.83 (p<0.001). Their mean difference was 21.7 micromol/l (SD 21.2, p<0.001), with the 95% limits of agreement between -19.9 and 63.3 micromol/l. In both low-risk and medium-risk thresholds for phototherapy, using the 75th centile of Bhutani's nomogram as threshold, TcB could identify all cases and had a sensitivity and negative predictive value of 100% each, a specificity of 56% and positive predictive value of 23%. For high-risk cases, using the 75th centile as cut-off, the sensitivity and negative predictive value were reduced to 86.7% and 97.0%, respectively.

CONCLUSION

An accurate point-of-care bilirubin analyser facilitates bilirubin screening and avoids unnecessary blood tests. Although using the transcutaneous bilirubinometer JM-103 might result in a significant difference between TcB and TSB measured in Chinese newborns, combining the use of TcB and the 75th centile in Bhutani's nomogram as the cut-off level can identify all cases of significant hyperbilirubinaemia.

Cysteine, cystine or N-acetylcysteine supplementation in parenterally fed neonates

BACKGROUND

L-cysteine is thought to be a conditionally essential (i.e., essential under certain conditions) amino acid for neonates. It is a precursor of glutathione, an antioxidant that may reduce oxidation injury. The addition of cysteine to parenteral nutrition (PN) allows for the reduction of the amount of methionine in PN, thereby limiting hepatotoxicity, and acidifies the solution, thereby increasing calcium and phosphate solubility, and potentially improving bone mineralization.

OBJECTIVES

To determine the effects of supplementing parenteral nutrition with cysteine, cystine or its precursor N-acetylcysteine on neonatal growth and short and long-term outcomes.

SEARCH STRATEGY

The standard search method of the Cochrane Neonatal Review Group was used. MEDLINE (1966-December 2005), EMBASE (1974-December 2005), the Cochrane Central Register of Controlled Trials (CENTRAL, The Cochrane Library, Issue 1, 2006) and recent abstracts (until December 2005) from the Society for Pediatric Research/American Pediatric Society, Eastern Society for Pediatric Research, and Society for Parenteral and Enteral Nutrition were searched.

SELECTION CRITERIA

All randomized (RCTs) and quasi-randomized trials that examined the effects of cysteine, cystine or N-acetylcysteine supplementation of neonatal PN were reviewed. Predetermined outcome variables included growth, nitrogen retention, mortality, morbidity secondary to oxidation injury, bone accretion, acidosis, liver disease, and cysteine levels.

DATA COLLECTION AND ANALYSIS

The standard methods of the Cochrane Collaboration and its Neonatal Review Group were used. Statistical analysis included relative risk, risk difference, and weighted mean difference (WMD).

MAIN RESULTS

Six trials fulfilled entry criteria. The majority of patients in these trials were preterm. Five small trials evaluated short-term cysteine supplementation of cysteine-free PN. One large multicenter RCT evaluated short-term N-acetylcysteine supplementation of cysteine-containing PN in extremely low birth weight infants (< or = 1000 grams).

PRIMARY OUTCOMES

Growth was not significantly affected by cysteine supplementation (evaluated in one quasi-randomized trial) or by N-acetylcysteine supplementation (evaluated in one RCT). Nitrogen retention was significantly increased by cysteine supplementation (studied in four trials) (WMD 31.8 mg/kg/day, 95% confidence interval +8.2, +55.4, n = 95, including 73 preterm infants).

SECONDARY OUTCOMES

Plasma levels of cysteine were significantly increased by cysteine supplementation but not by N-acetylcysteine supplementation. N-acetylcysteine supplementation did not significantly affect the risks of death by 36 postmenstrual weeks, bronchopulmonary dysplasia (BPD), death or BPD, retinopathy of prematurity (ROP), severe ROP, necrotizing enterocolitis requiring surgery, periventricular leukomalacia, intraventricular hemorrhage (IVH), or severe IVH. No data were available on other outcomes.

AUTHORS' CONCLUSIONS

Available evidence from RCTs shows that routine short-term cysteine chloride supplementation of cysteine-free PN in preterm infants improves nitrogen balance.However, there is insufficient evidence to assess the risks of cysteine supplementation, especially regarding metabolic acidosis, which has been reported during the first two weeks of cysteine chloride administration. Available evidence from a large RCT trial does not support routine N-acetylcysteine supplementation of cysteine-containing PN in extremely low birth weight infants. A large RCT would be required to assess whether routine prolonged cysteine supplementation of cysteine-free PN affects growth and short and long-term neonatal outcomes in very low birth weight infants.

Incidence and causes of severe neonatal hyperbilirubinemia in Canada

BACKGROUND

Severe hyperbilirubinemia is the most common cause of neonatal readmission to hospital in Canada even though, in the majority of cases, risk factors can be identified before discharge. Severe neonatal hyperbilirubinemia and kernicterus continue to be reported worldwide in otherwise healthy term infants. We conducted this study to estimate the incidence of severe neonatal hyperbilirubinemia in Canada and to determine underlying causes, improved knowledge of which would be valuable to help identify strategies for risk reduction.

METHODS

Data on term infants 60 days of age and younger with unconjugated hyperbilirubinemia were collected prospectively through the Canadian Paediatric Surveillance Program from 2002 to 2004. Infants were included if they had a peak serum total bilirubin level of more than 425 micromol/L or underwent an exchange transfusion. Infants with rhesus iso-immunization or who were born at less than 36 weeks' gestation were excluded.

RESULTS

Of 367 cases reported, 258 were confirmed to be severe neonatal hyperbilirubinemia, for an estimated incidence of 1 in 2480 live births. Causes were identified in 93 cases and included ABO incompatibility (n = 48), glucose-6-phosphate dehydrogenase deficiency (n = 20), other antibody incompatibility (n = 12) and hereditary spherocytosis (n = 7). The mean peak bilirubin level reported was 471 micromol/L (standard deviation [SD] 76 micromol/L, range 156-841 micromol/L). Fifty-seven infants (22.1%) underwent an exchange transfusion. A total of 185 infants (71.7%) were readmitted to hospital, 121 (65.4%) of them within 5 days of age.

INTERPRETATION

Severe neonatal hyperbilirubinemia continues to occur frequently in Canada. In the majority of cases, the underlying cause was not identified. The high readmission rate within days after initial discharge indicates a need for a more thorough assessment of newborn infants and consideration of strategies to identify at-risk newborns, such as predischarge measurement of serum bilirubin levels.

A systems approach for neonatal hyperbilirubinemia in term and near-term newborns

OBJECTIVE

To propose and implement a family-centered systems approach to manage newborn jaundice for safer outcomes.

DESIGN

Observational study for known adverse outcomes.

SETTING

Semiprivate urban birthing hospital.

PATIENTS/PARTICIPANTS

31,059 well babies discharged as healthy from a cohort of 41,961 live births (1990-2000).

INTERVENTIONS

Incremental implementation of a systems approach that incorporated a hospital policy to (a) authorize nurses to obtain a bilirubin (total serum/transcutaneous) measurement for clinical jaundice, (b) universal predischarge total serum bilirubin (at routine metabolic screening), and (c) targeted follow-up, using the bilirubin nomogram (hour-specific, percentile-based total serum bilirubin/transcutaneous bilirubin).

MAIN OUTCOME MEASURES

Known adverse outcomes assessed for early- and late-onset severe hyperbilirubinemia before, during, and after systems approach implementation.

RESULTS

Adverse outcomes decreased for well babies: exchange transfusion, intensive phototherapy, and readmission. During the study period, there were no "never events" (total serum bilirubin greater than or equal to 30 mg/dl), while "close calls" (total serum bilirubin greater than or equal to 25 mg/dl) were 1 in 15,000 as compared to a reported incidence of 1 in 625.

CONCLUSIONS

Reduced adverse events, significant reduction in close calls, and no never events met family expectations for safer experiences with this approach.

Does intensive phototherapy produce hemolysis in newborns of 35 or more weeks gestation?

OBJECTIVE

Because there is some in vivo and in vitro evidence that standard phototherapy might produce hemolysis, we wished to know whether intensive phototherapy produces hemolysis.

STUDY DESIGN

We measured end-tidal carbon monoxide (CO) concentration corrected for ambient CO (ETCOc) in 27 newborn infants > or =35 weeks gestation receiving intensive phototherapy (average irradiance 43 microW/cm2/nm).

RESULTS

There was a steady decrease in the mean ETCOc over the course of the phototherapy.

CONCLUSION

Intensive phototherapy did not produce hemolysis in infants > or =35 weeks gestation.

Unconjugated bilirubin modulates the intestinal epithelial barrier function in a human-derived in vitro model

Unconjugated bilirubin promotes intestinal secretion without affecting nutrient digestion or absorption. In the current study, the effects of unconjugated bilirubin (UCB) on the barrier function of the intestinal epithelium were investigated. The apical side of human intestinal cell line Caco-2 monolayers was challenged with purified UCB. Transepithelial electrical resistance and paracellular fluxes of 10 kD Cascade blue conjugate dextran were measured. Cell monolayer viability was studied using LDH release and trypan blue exclusion tests. Redistribution of enterocyte tight junction occludin was studied by confocal microscopy. Bilirubin induced a dose-dependent decrease of transepithelial electrical resistance (TEER). This effect was maximal at 6 h and tended to be reversed at 48 h. Oxidated bilirubin was ineffective. Bilirubin significantly increased fluorescent dextran paracellular passage. Cell viability was not affected by UCB over the 5-200 nmol/L concentration range. Finally, bilirubin triggered a reversible redistribution of tight junctional occludin. UCB increases the permeability of intestinal epithelium. This effect is reversible, dependent on the redox status of the molecule and the rearrangement of the tight junction. These data attribute to bilirubin a novel role of functional modulator of intestinal paracellular permeability in vitro.

Neonatal hyperbilirubinemia in African American males: the importance of glucose-6-phosphate dehydrogenase deficiency

OBJECTIVE

To perform risk factor analysis for the prediction of hyperbilirubinemia in an African American male neonatal cohort.

STUDY DESIGN

A database of 500 previously published term and near-term African American male neonates was further analyzed to determine the role of risk factors for hyperbilirubinemia. Factors studied included birth weight >/=4.0 kg, gestational age /=75(th) percentile. Hyperbilirubinemia was defined as any bilirubin value >/=95(th) percentile on the hour-of-life-specific bilirubin nomogram.

RESULTS

Forty-three (8.6%) neonates developed hyperbilirubinemia. At 48 +/- 12 hours, median transcutaneous bilirubin was 8.3 mg/dL, 75(th) percentile 10.0 mg/dL, and 95(th) percentile 12.6 mg/dL. Of the risk factors, only exclusive breast-feeding, G-6-PD deficiency and predischarge bilirubin >/=75(th) percentile were significant (Adjusted Odds Ratios [95% Confidence Intervals; CI] 3.15 [1.39-7.14], P = .006; 4.96 [2.28-10.80], P = .001; and 7.47 [3.50-15.94], P < .0001, respectively). G-6-PD-deficient neonates who were also premature and breast-feeding had the highest incidence of hyperbilirubinemia (60%).

CONCLUSIONS

African American male neonates may be at higher risk for hyperbilirubinemia than previously thought. Screening for G-6-PD deficiency and predischarge bilirubin determination may be useful adjuncts in hyperbilirubinemia prediction in these newborns.

Bilirubin toxicity to human erythrocytes: a review

Neonatal jaundice, a physiologic condition reflecting the interplay between developmentally modulated changes in bilirubin production and metabolism, affects virtually all newborn infants. Usually, it is an entirely benign process that is resolved at the end of the first week of life without treatment or sequelae. However, in a small percentage of neonates, unconjugated hyperbilirubinemia can pose a neurotoxic risk especially in the presence of aggravating conditions such as a diminished albumin binding capacity and/or affinity, acidosis, displacing drugs and prematurity. Although neuronal cells are considered the main target for unconjugated bilirubin (UCB) toxicity, circulating cells are also affected during neonatal hyperbilirubinemia. Moreover, the UCB ability to cause hemolysis shall further aggravate neonatal jaundice through a vicious circle. In this review, we summarize the most relevant data obtained by our group regarding UCB toxicity and the role of some risk factors for kernicterus. In order to improve the risk assessment of neurotoxicity it is essential to understand the underlying mechanisms of UCB pathophysiology.

Which phototherapy system is most effective in lowering serum bilirubin in very preterm infants?

OBJECTIVE

To compare the effectiveness of various phototherapy systems in lowering serum bilirubin levels in preterm infants.

METHODS

This randomized clinical trial enrolled 140 preterm infants with gestational age < or =30 weeks and presenting nonhemolytic hyperbilirubinemia. When total serum bilirubin level reached 6.0 mg/dl (102.6 micromol/l), eligible infants were randomly assigned to four study groups: conventional, fiberoptic Wallaby, fiberoptic Biliblanket, and combined phototherapy. Efficacy was assessed by comparing highest serum bilirubin levels, duration of treatment, and number of infants requiring exchange transfusion.

RESULTS

Our results confirm that fiberoptic phototherapy, both Wallaby and Biliblanket, had the same effectiveness of conventional phototherapy. The best results have been obtained using combined phototherapy, which allowed to reach lower serum bilirubin levels, a shorter duration of treatment and a significant reduction of exchange transfusions.

CONCLUSION

Our data suggest that combined phototherapy should be the method of choice in treating hyperbilirubinemia in very preterm infants.

Immunizations, neonatal jaundice and animal-induced injuries

PURPOSE OF REVIEW

To review the literature published within the last year on three topics essential to clinical pediatrics: immunizations, neonatal jaundice, and animal-induced injuries.

RECENT FINDINGS

New vaccines that protect against meningococcus, pertussis and rotavirus are safe, effective and recommended for routine immunization. Young children remain a high priority for influenza vaccination while the world awaits further developments of avian influenza. Pneumococcal and varicella vaccinations have benefited many. Debate exists on how to screen for hyperbilirubinemia in neonates and new strategies are emerging to prevent it. There seems to be no link between hyperbilirubinemia and autism spectrum disorders. We have learned that rabies can be transmitted by transplantation; it remains a global public health problem and its incidence is frequently underestimated in developing nations. Lastly, brown recluse spider bites are often misdiagnosed.

SUMMARY

The face of pediatric infectious disease is changing as we incorporate new vaccines into our routine practice. Rotavirus vaccine has significant implications for the health of children across the globe. The management strategy for neonatal jaundice continues to focus on screening and prevention. We need to devote more energy to combating rabies in countries where it is endemic.

Early recognition of neonatal hyperbilirubinemia and its emergent management

Hyperbilirubinemia and kernicterus are re-emerging as prominent clinical concerns and have been hypothesized to be secondary to increased breast-feeding rates, early hospital discharges and overall lack of concern for the potential impact of severe hyperbilirubinemia on healthy term newborns. Although the clinical symptoms can be non-specific and vague, they could be early, insidious and heralding signs of acute bilirubin encephalopathy (ABE) or acute stage kernicterus. Because it is highly prevalent, evaluation of a jaundiced neonate requires detailed questions about specific signs, review of birth and postnatal histories, evaluation of predischarge data, and possibly an emergency clinical evaluation of the neurological status of the infant. Medical urgency to evaluate, investigate and monitor such a newborn ensues from the possibility of rapid progression that might lead to permanent sequelae of bilirubin-induced neurologic dysfunction (BIND). Early recognition of the urgency and rapid transition to treatment seem to be the major barriers leading to delay in therapy. However, because there is a well-established and relatively safe treatment for neonatal jaundice, there should be zero tolerance for kernicterus, and BIND prevention has become a national priority in the USA. This paper reviews the clinical signs and epidemiology of ABE and BIND and presents a system-based strategy for preventing their occurrence, focusing particularly on the transition from recognition of clinical jaundice to actual treatment. A novel emergency-room-based protocol is presented as an example of how to expedite and facilitate rapid progression to treatment.

Biochemistry testing associated with pregnancy and the newborn period -- a lot has changed since you were a baby!

Everyone has been a newborn, and everyone's mother has been pregnant. Despite the commonality of these events, medical care and the clinical chemistry laboratory's role in it have changed remarkably over the last 50 years. This review is a historical overview of clinical chemistry testing that is related to pregnancy and the newborn period.

Characterization of neuronopathic Gaucher disease among ethnic Poles

PURPOSE

Gaucher disease is a common lysosomal storage disease that results from inherited mutations in the gene (GBA) encoding acid beta-glucosidase (GCase). Here, the clinical and molecular findings of the subacute neuronopathic variant are delineated among ethnic Poles.

METHODS

Longitudinal studies of visceral, bony, and central nervous system involvement are delineated clinically. Complete gene GBA sequencing was used to characterize the mutations and haplotypes in this population.

RESULTS

A greater frequency of subacute neuronopathic Gaucher disease (type 3) is present among ethnic Poles compared with other European countries. Two type 3 phenotypes were found: The first was an early-onset variant with massive visceral disease, progressive kyphoscoliosis, mild cognitive deficits, and survival for three or more decades. This variant resembles the "Norrbottnian" Swedish phenotype. The other variant had more severe progressive central nervous system disease, milder visceral involvement, and absence of kyphoscoliosis. Myoclonus was present in some patients. Neither variant had bone crises and/or pain as major components. The L444P/L444P genotype was most common, but on several different haplotype backgrounds. Other alleles encoded D409H, V305L, and E326K/A446P on various haplotypes.

CONCLUSIONS

These studies provide additional expansion of the type 3 genotypes with some commonalities with and differences from other reported variants. Also, such phenotypic expansion should be expected in the other variants of Gaucher disease as the spectrum of ethnic variation becomes more fully delineated.

Outcomes among newborns with total serum bilirubin levels of 25 mg per deciliter or more

BACKGROUND

The neurodevelopmental risks associated with high total serum bilirubin levels in newborns are not well defined.

METHODS

We identified 140 infants with neonatal total serum bilirubin levels of at least 25 mg per deciliter (428 micromol per liter) and 419 randomly selected controls from a cohort of 106,627 term and near-term infants born from 1995 through 1998 in Kaiser Permanente hospitals in northern California. Data on outcomes were obtained from electronic records, interviews, responses to questionnaires, and neurodevelopmental evaluations that had been performed in a blinded fashion.

RESULTS

Peak bilirubin levels were between 25 and 29.9 mg per deciliter (511 micromol per liter) in 130 of the newborns with hyperbilirubinemia and 30 mg per deciliter (513 micromol per liter) or more in 10 newborns; treatment involved phototherapy in 136 cases and exchange transfusion in 5. Follow-up data to the age of at least two years were available for 132 of 140 children with a history of hyperbilirubinemia (94 percent) and 372 of 419 controls (89 percent) and included formal evaluation at a mean (+/-SD) age of 5.1+/-0.12 years for 82 children (59 percent) and 168 children (40 percent), respectively. There were no cases of kernicterus. Neither crude nor adjusted scores on cognitive tests differed significantly between the two groups; on most tests, 95 percent confidence intervals excluded a 3-point (0.2 SD) decrease in adjusted scores in the hyperbilirubinemia group. There was no significant difference between groups in the proportion of children with abnormal neurologic findings on physical examination or with documented diagnoses of neurologic abnormalities. Fourteen of the children with hyperbilirubinemia (17 percent) had "questionable" or abnormal findings on neurologic examination, as compared with 48 controls (29 percent; P=0.05; adjusted odds ratio, 0.47; 95 percent confidence interval, 0.23 to 0.98; P=0.04). The frequencies of parental concern and reported behavioral problems also were not significantly different between the two groups. Within the hyperbilirubinemia group, those with positive direct antiglobulin tests had lower scores on cognitive testing but not more neurologic or behavioral problems.

CONCLUSIONS

When treated with phototherapy or exchange transfusion, total serum bilirubin levels in the range included in this study were not associated with adverse neurodevelopmental outcomes in infants born at or near term.

The effect of instituting a prehospital-discharge newborn bilirubin screening program in an 18-hospital health system

OBJECTIVE

Kernicterus is a rare but devastating condition. The prevention of bilirubin-induced brain injury is based on the detection of infants at risk for developing severe hyperbilirubinemia. In an 18-hospital health system, Intermountain Health Care (IHC), we initiated a program of predischarge bilirubin screening of all neonates and coupled this with a results assessment using a percentile-based nomogram. Data during 2 periods of time, before versus after initiating the program, were compared to assess the effect of the program on significant hyperbilirubinemia and rehospitalization.

METHODS

We conducted a historic cohort study involving all neonates delivered at > or =35 weeks' gestation, within IHC's 18-hospital system, during 2 periods of time: March 1, 2001, to December 31, 2002, versus January 1, 2003, to December 31, 2004. A bilirubin screening program, instituted in December 2002, called for a total serum bilirubin (TSB) or transcutaneous bilirubin measurement to be performed on every neonate either at the recognition of clinical jaundice or before discharge regardless of whether jaundice was observed. For nonjaundiced neonates, the nursery staff was encouraged to obtain the screening TSB at the same time they obtained the state-mandated newborn screen for inborn errors of metabolism. Bilirubin values were plotted on an hour-specific nomogram and the corresponding percentile was used to guide evaluation, therapy, and follow-up. This study compared TSB data and readmission data for a 2-year period before versus a 2-year period after implementing the program.

RESULTS

The study involved 101272 neonates: 48789 in period 1 and 52483 in period 2. Before the program, 1 in every 77 neonates born at an IHC hospital had 1 or more serum bilirubin levels >20 mg/dL. After initiating the program, the incidence fell to 1 in 142 and the number of neonates with a level >25 mg/dL fell from 1 in 1522 before to 1 in 4037 after. The rate of hospital readmission with a primary diagnosis of jaundice fell from 0.55% in period 1 to 0.43% in period 2.

CONCLUSIONS

Initiating a program of bilirubin screening in a multihospital health system, coupled with evaluating the results using a percentile-based nomogram, reduced the proportion of neonates with significant hyperbilirubinemia and reduced the rate of hospital readmissions with jaundice.

Management of hyperbilirubinemia and prevention of kernicterus in 20 patients with Crigler-Najjar disease

We summarize the treatment of 20 patients with Crigler-Najjar disease (CND) managed at one center from 1989 to 2005 (200 patient-years). Diagnosis was confirmed by sequencing the UGTA1A gene. Nineteen patients had a severe (type 1) phenotype. Major treatment goals were to maintain the bilirubin to albumin concentration ratio at <0.5 in neonates and <0.7 in older children and adults, to avoid drugs known to displace bilirubin from albumin, and to manage temporary exacerbations of hyperbilirubinemia caused by illness or gallstones. A variety of phototherapy systems provided high irradiance over a large body surface. Mean total bilirubin for the group was 16+/-5 mg/dl and increased with age by approximately 0.8 mg/dl per year. The molar ratio of bilirubin to albumin ranged from 0.17 to 0.75 (mean: 0.44). The overall non-surgical hospitalization rate was 0.12 hospitalizations per patient per year; one-half of these were for neonatal hyperbilirubinemia and the remainder were for infectious illnesses. Ten patients (50%) underwent elective laproscopic cholecystectomy for cholelithiasis. No patient required invasive bilirubin removal or developed bilirubin-induced neurological damage under our care. Visual acuity and color discrimination did not differ between CND patients and age-matched sibling controls. Four patients treated with orthotopic liver transplantation were effectively cured of CND, although one suffered significant transplant-related complications.Conclusions. While patients await liver transplantation for CND, hyperbilirubinemia can be managed safely and effectively to prevent kernicterus. Lessons learned from CND can be applied to screening and therapy of non-hemolytic jaundice in otherwise healthy newborns.

A Concept Analysis of Effective Breastfeeding

OBJECTIVE

To provide a concept analysis of effective breastfeeding.

DATA SOURCES

Medline and CINAHL electronic databases, reference lists from selected articles, and 7 breastfeeding assessment tools. Search terms included the following: breastfeeding and effective, adequate, successful.

STUDY SELECTION

Literature was selected according to whether the concept of effective breastfeeding was defined or described.

DATA EXTRACTION

Literature was reviewed and data organized as definitions or descriptions, with descriptions grouped into categories sharing similar characteristics.

DATA SYNTHESIS

Four characteristics were chosen as essential attributes of effective breastfeeding: positioning, latch, sucking, and milk transfer.

CONCLUSIONS

The concept of effective breastfeeding requires further concept development to define and describe effective positioning, latch, sucking, and milk transfer. Future research is needed to determine the relationships between the antecedents, attributes, and consequences of effective breastfeeding.

The changing face of race: risk factors for neonatal hyperbilirubinemia

OBJECTIVES

Race is a predictor of health outcomes and risk for some clinical conditions, for example, mother's race predicts risk for hyperbilirubinemia in newborns, with blacks at lowest risk. Little is known about the correlation of race as recorded in medical records with self-reported race. Also, use of maternal race to predict newborn risk for hyperbilirubinemia has not been tested for multiracial mothers and newborns. We sought to examine how maternal race documented in medical records correlates with self-reported race and to examine the correlation between mothers' and newborns' race in the context of risk for neonatal hyperbilirubinemia, focusing on multiracial mothers and newborns.

DESIGN

A cohort study with 3021 newborns at > or =35 weeks gestation discharged from normal nursery between January 2001 and October 2002 with a telephone survey of their mothers within 6 months of birth.

SETTING

The study was conducted in the Neonatology Department of Henry Ford Hospital.

PATIENTS

There were 1773 mothers (58%) with incorrect telephone numbers. Of 1248 mothers contacted, 866 (69%) completed the interview.

OUTCOME MEASURES

We measured mother's race in hospital database and mother's reported race for herself, her newborn, and the father, allowing < or =5 responses for each.

RESULTS

Of mothers documented in the medical record as white, 64% self-reported as white. Among mothers recorded as black, 70% self-reported as black. Mothers identified 93 newborns as > or =2 races with primary race matching both parents for 41%, father for 25%, mother for 23%, and neither parent for 11%. Of 70 newborns whose parents were not the same race, mothers identified 45 (64%) as > or =2 races.

CONCLUSIONS

There is incomplete overlap between racial identification in medical records versus self-report. Given 1 choice, mothers of multiracial infants overselect black in their newborns' ancestry. Because black race is the lowest risk category for neonatal hyperbilirubinemia, this may lead to underestimating their risk.

Main Report

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