Risk factors for severe hyperbilirubinemia among infants with borderline bilirubin levels: a nested case-control study

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

BACKGROUND AND OBJECTIVES

Guidelines for the management of neonatal hyperbilirubinemia have helped to reduce rates of significant hyperbilirubinemia. However, recent evidence suggesting overtreatment and potential harms of phototherapy have informed the American Academy of Pediatrics clinical practice guideline revision and the accompanying increase in phototherapy thresholds. These changes are predicted to safely reduce overuse; however, to date, the exact effect of these guidelines has not been established.

METHODS

We conducted a retrospective study of newborns born at ≥35 weeks' gestation across a network of 8 hospitals between January 2022 and June 2023. Outcomes included rates of phototherapy and total serum bilirubin (TSB) measurements before and after guideline publication, as well as clinical outcomes, including length of stay, readmissions, and duration of phototherapy.

RESULTS

In our cohort of >22 000 newborns, we observed a 47% decrease in phototherapy utilization, from 3.9% to 2.1% (P < .001). TSB measurements were reduced by 23%, from 712 to 551 measurements per 1000 newborns (P < .001), without an increase in outpatient TSB measurements. We did not observe an increase in readmissions receiving phototherapy, and length of stay increased by only 1 hour (P < .001).

CONCLUSIONS

Our study reveals that the publication of the updated American Academy of Pediatrics 2022 hyperbilirubinemia guidelines has likely yielded a significant reduction in phototherapy use and serum bilirubin measurement. Dedicated quality improvement initiatives may help determine which implementation strategies are most effective. Further population-level studies are needed to confirm safety with ongoing guideline uptake.

Implementing Higher Phototherapy Thresholds for Jaundice in Healthy Infants 35 Plus Weeks

OBJECTIVES

To determine the impact of higher bilirubin thresholds on testing and treatment of healthy infants during the neonatal period.

METHODS

This quality improvement study included infants born at ≥35 weeks gestation and admitted to the well-baby nursery between July 2018 and December 2020. We assessed the transition from infants treated according to the 2004 AAP guidelines (pregroup) with those following the Northern California Neonatal Consortium guidelines (postgroup). We examined the proportion of infants receiving phototherapy and total serum bilirubin (TSB) assessments as outcome measures. We examined critical hyperbilirubinemia (TSB above 25 mg/dL or TSB within 2 mg/dL of threshold for exchange transfusion), exchange transfusion, and readmission for jaundice as balancing measures. We compared the differences in outcomes over time using Statistical Process Control p charts. Balancing measures between the pre and postgroups were compared using χ square tests and t-tests.

RESULTS

In our population of 6173 babies, there was a significant shift in the proportion receiving phototherapy from 6.4% to 4%. There were no significant changes in incidences of bilirubin >25 mg/dL (0 of 1472 vs 7 of 4709, P = .37), bilirubin within 2 mg/dL of exchange transfusion thresholds (4 of 1472 vs 5 of 4709, P = .15), exchange transfusion (0 of 1472 vs 1 of 4709, P = .70) or readmission for phototherapy (2.9% versus 2.4%, P = .30), between the 2 groups.

CONCLUSIONS

Higher thresholds for phototherapy treatment of neonatal hyperbilirubinemia can decrease the need for phototherapy without increasing critical hyperbilirubinemia or readmission rate.

Effects of Repetitive Transcranial Magnetic Stimulation on Pallidum GABAergic Neurons and Motor Function in Rat Models of Kernicterus

Kernicterus is a serious complication of hyperbilirubinemia, caused by neuronal injury due to excessive unconjugated bilirubin (UCB) in specific brain areas. This injury induced by this accumulation in the globus pallidus can induce severe motor dysfunction. Repetitive transcranial magnetic stimulation (rTMS) has shown neuroprotective effects in various neurological diseases. This study aimed to investigate the effects of rTMS on pallidal nerve damage and motor dysfunction in a rat model of kernicterus. Rats were divided into a sham group (n = 16), a model group (bilirubin with sham rTMS; n = 16) and an rTMS group (bilirubin with rTMS; n = 16). High-frequency rTMS (10 Hz) was applied starting from 24 h postmodeling for 7 days. The rotarod test, western blotting and immunohistochemical staining were performed to measure motor function and protein expression levels. The rTMS mitigated the negative effects of UCB on the general health of kernicterus-model rats and improved their growth and development. Furthermore, the rTMS alleviated UCB-induced motor dysfunction and increased the expression of GABAergic neuronal marker GAD67 in the globus pallidus. Notably, it also inhibited apoptosis-related protein caspase-3 activation. In conclusion, rTMS could alleviate motor dysfunction by inhibiting apoptosis and increasing globus pallidus GAD67 in kernicterus rat models, indicating that it may be a promising treatment for kernicterus.

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.

Human Milk for the Term Newborn

Human milk provides optimal nutrition for term newborns, but the prevalence of its use is below target, and risks have been identified. Infants of black mothers as well as term newborns admitted to the neonatal intensive care unit are at risk for not receiving human milk. To improve human milk intake, multiple individual-level interventions have been shown to be effective, but some popular system-level interventions are ineffective or harmful. Expressed milk and donor milk may be less beneficial than direct breastfeeding. Nuanced public policies can help support lactation while promoting individual choice and equity.

Transient Effect of Infant Formula Supplementation on the Intestinal Microbiota

Breastfeeding is the gold standard for feeding infants because of its long-term benefits to health and development, but most infants in the United States are not exclusively breastfed in the first six months. We enrolled 24 infants who were either exclusively breastfed or supplemented with formula by the age of one month. We collected diet information, stool samples for evaluation of microbiotas by 16S rRNA sequencing, and blood samples for assessment of immune development by flow cytometry from birth to 6 months of age. We further typed the Bifidobacterium strains in stool samples whose 16S rRNA sequencing showed the presence of Bifidobacteriaceae. Supplementation with formula during breastfeeding transiently changed the composition of the gut microbiome, but the impact dissipated by six months of age. For example, Bifidobacterium longum, a bacterial species highly correlated with human milk consumption, was found to be significantly different only at 1 month of age but not at later time points. No immunologic differences were found to be associated with supplementation, including the development of T-cell subsets, B cells, or monocytes. These data suggest that early formula supplementation, given in addition to breast milk, has minimal lasting impact on the gut microbiome or immunity.

Bilirubin Induced Encephalopathy

Hyperbilirubinemia is one of the most common neonatal disorders. Delayed diagnosis and treatment of the pathologic and progressive indirect hyperbilirubinemia lead to neurological deficits, defined as bilirubin induced encephalopathy (BIE) (2). The incidence of this disorder in underdeveloped countries is much more than developed areas. All neonates with the risk factors for increased the blood level of indirect bilirubin are at risk for BIE, especially preterm neonates which are prone to low bilirubin kernicterus . BIE can be transient and acute (with early, intermediate and advanced phases)or be permanent, chronic and lifelong ( with tetrad of symptoms including visual (upward gaze palsy), auditory (sensory neural hearing loss), dental dysplasia abnormalities, and extrapyramidal disturbances (choreoathetosis cerebral palsy).Beside the abnormal neurologic manifestations of the jaundiced neonates ,brain MRI is the best imaging modality for the confirmation of the diagnosis. Although early treatment of extreme hyperbilirubinemia by phototherapy and exchange transfusion can prevent the BIE, unfortunately the chronic bilirubin encephalopathy does not have definitive treatment.

The Choice of Population and Outcomes in Neonatal Trials on Hyperbilirubinemia: Are They Relevant? An Analysis of Cochrane Neonatal Reviews

BACKGROUND

Neonates with jaundice are usually managed according to their serum bilirubin despite an unclear overall correlation between bilirubin levels and patient-important outcomes (PIOs) such as kernicterus spectrum disorder (KSD).

OBJECTIVES

We examined data from Cochrane Neonatal reviews to assess whether conditions that constituted KSD were included as key outcomes and how commonly they occurred in the population studied.

METHODS

We identified Cochrane reviews, published till November 2017 that evaluated interventions for neonatal jaundice (NNJ). We extracted the following information at the review and study levels: included population, outcomes assessed (in particular, whether PIOs such as KSD were listed as the primary outcomes), as well as their cumulative incidence in the reviews.

RESULTS

Out of 311 reviews, 11 evaluated interventions for NNJ with 78 randomized controlled trials (RCTs) included. Among the reviews, a total number of 148 outcomes were predefined and 30 (20.3%) were PIOs related to KSD, with 11 (36.7%) listed as primary outcomes. Among the 78 included RCTs (total participants = 8,232), 38 (48.7%) enrolled predominantly high-risk and 40 (51.3%) enrolled predominantly low-risk population. A total number of 431 outcomes were reported, and 40 (9.2%) were PIOs related to KSD (of which 37 were from studies with high-risk infants), with 13 (32.5%) listed as primary outcome. Cumulatively, no infant developed KSD across all studies.

CONCLUSIONS

There is suboptimal representation of PIOs such as KSD in neonatal trials and Cochrane reviews on NNJ. Over half of the trials included populations with very low risk of KSD, which does not represent judicious use of resources. Amidst our continued search for a more reliable surrogate marker for NNJ, studies should evaluate the whole spectrum KSD alongside serum bilirubin in high-risk populations with sufficiently significant event rates, as this will make the trial methodologically feasible, with findings that will impact the population concerned.

High unbound bilirubin for age: a neurotoxin with major effects on the developing brain

Neonatal hyperbilirubinemia is one of the most frequent diagnoses made in neonates. A high level of unconjugated bilirubin that is unbound to albumin is neurotoxic when the level exceeds age-specific thresholds or at lower levels in neonates with neurotoxic risk factors. Lower range of unbound bilirubin results in apoptosis, while moderate-to-high levels result in neuronal necrosis. Basal ganglia and various brain stem nuclei are more susceptible to bilirubin toxicity. Proposed mechanisms of bilirubin-induced neurotoxicity include excessive release of glutamate, mitochondrial energy failure, release of proinflammatory cytokines, and increased intracellular calcium concentration. These mechanisms are similar to the events that occur following hypoxic-ischemic insult in neonates. Severe hyperbilirubinemia in term neonates has been shown to be associated with increased risk for autism spectrum disorders. The neuropathological finding of bilirubin-induced neurotoxicity also includes cerebellar injury with a decreased number of Purkinje cells, and disruption of multisensory feedback loop between cerebellum and cortical neurons which may explain the clinical characteristics of autism spectrum disorders. Severe hyperbilirubinemia occurs more frequently in infants from low- and middle-income countries (LMIC). Simple devices to measure bilirubin, and timely treatment are essential to reduce neurotoxicity, and improve outcomes for thousands of neonates around the world.

Health Care Utilization in the First Month After Birth and Its Relationship to Newborn Weight Loss and Method of Feeding

OBJECTIVE

Guidelines recommend closer outpatient follow-up for exclusively breastfed newborns, especially those with pronounced weight loss, because of increased risk of hyperbilirubinemia and dehydration that might require readmission. Our objective was to determine how feeding method and weight loss are associated with neonatal health care utilization.

METHODS

A retrospective cohort study conducted at Northern California Kaiser Permanente hospitals in 2009-2013 assessed 143,889 neonates to study the inpatient method of feeding as well as inpatient and outpatient weights. The main outcome measures were inpatient and outpatient health care utilization in the 30 days after birth.

RESULTS

Newborn weight loss and feeding method were both associated with utilization. Exclusively breastfed newborns had higher readmission rates than those exclusively formula fed for both vaginal (4.3% compared to 2.1%) (P < .001) and cesarean deliveries (2.1% compared to 1.5%) (P = .025). Those exclusively breastfed also had more neonatal outpatient visits compared to those exclusively formula fed for both vaginal (means of 3.0 and 2.3, P < .001) and cesarean deliveries (means of 2.8 and 2.2, P < .001). Among vaginally delivered newborns of all feeding types, newborns with weight loss >10% at discharge had a relative risk of readmission of 1.10 (95% confidence interval [CI],1.00, 1.20) compared to those with <8% weight loss at discharge; among the subset weighed as inpatients or outpatients between 48 and 72 hours, those with >10% weight loss between 48-72 hours had a relative risk of readmission of 2.11 (95% CI, 1.95, 2.26) compared to those with <8% weight loss at 48-72 hours.

CONCLUSIONS

Exclusive breastfeeding and weight loss are associated with increased neonatal health care utilization. Improving clinical management of exclusively breastfed neonates with pronounced weight loss might reduce health care utilization.

The Effect of Early Limited Formula on Breastfeeding, Readmission, and Intestinal Microbiota: A Randomized Clinical Trial

OBJECTIVE

To determine whether using 10 mL formula after each breastfeeding before copious maternal milk production affects breastfeeding duration, readmission, and intestinal microbiota through 1 month of age.

STUDY DESIGN

In this randomized controlled trial, we enrolled 164 exclusively breastfeeding newborns, 24-72 hours old, whose weight loss was ≥75th percentile for age, and whose mothers had not yet begun mature milk production. Enrolled newborns were assigned randomly to either supplement breastfeeding with early limited formula (ELF), 10 mL of formula after each breastfeeding stopped at the onset of copious maternal milk production (intervention), or to continue exclusive breastfeeding (control). Outcomes assessed through 1 month included breastfeeding duration, readmission, and intestinal microbiota.

RESULTS

At 1 week of age, 95.8% of infants receiving ELF and 93.5% of control infants were still breastfeeding (P > .5); readmission occurred for 4 (4.8%) control infants and none of the infants receiving ELF (P = .06). At 1 month of age, 86.5% of infants receiving ELF and 89.7% of control infants were still breastfeeding (P > .5); 54.6% of infants receiving ELF and 65.8% of controls were breastfeeding without formula (P = .18). ELF did not lead to decreased abundance of Lactobacillus or Bifidobacterium and was not associated with expansion of Clostridium.

CONCLUSION

In this population of healthy newborns with weight loss ≥75th percentile, ELF did not interfere with breastfeeding at 1 month, breastfeeding without formula at 1 month, or intestinal microbiota. ELF may be an important therapeutic option for newborns with the potential to reduce readmission rates.

TRIAL REGISTRATION

Clinicaltrials.gov: NCT02313181.

Efficacy of Subthreshold Newborn Phototherapy During the Birth Hospitalization in Preventing Readmission for Phototherapy

IMPORTANCE

Treatment of jaundiced newborns with subthreshold phototherapy (phototherapy given to newborns with bilirubin levels below those recommended in American Academy of Pediatrics [AAP] guidelines) is common. However, the use of subthreshold phototherapy may have risks and increase costs, and, to date, it has not been systematically studied in newborns.

OBJECTIVES

To estimate the efficacy of subthreshold phototherapy for newborns with total serum bilirubin (TSB) levels from 0.1 to 3.0 mg/dL below the appropriate AAP phototherapy threshold during the birth hospitalization in preventing readmissions for phototherapy, and to identify predictors of readmission for phototherapy.

DESIGN, SETTING, AND PARTICIPANTS

Retrospective cohort study of 25 895 newborns born at 35 or more weeks' gestation, born in 1 of 16 Kaiser Permanente Northern California hospitals from January 1, 2010, through December 31, 2014, with at least 1 TSB level from 0.1 to 3.0 mg/dL below the appropriate AAP phototherapy threshold and not exceeding the threshold during the birth hospitalization. Data were analyzed from November 1, 2015, to November 28, 2017.

EXPOSURE

Subthreshold phototherapy during the birth hospitalization.

MAIN OUTCOMES AND MEASURES

Readmission for phototherapy.

RESULTS

Among 25 895 newborns with qualifying TSB levels from 0.1 to 3.0 mg/dL below the appropriate AAP phototherapy threshold, 4956 (19.1%) received subthreshold phototherapy and 241 of these (4.9%) were readmitted for phototherapy compared with 2690 of 20 939 untreated newborns (12.8%) (unadjusted odds ratio [OR], 0.35; 95% CI, 0.30-0.40). In a logistic regression model, adjustment for confounding variables, including gestational age, race/ethnicity, formula feedings per day, and the difference between the TSB level and the phototherapy threshold, strengthened the association (OR, 0.28; 95% CI, 0.19-0.40). Estimated numbers needed to treat ranged from 60.8 in the lowest quintile of predicted risk to 6.3 in the highest quintile. Newborns who received formula feedings had lower adjusted odds of readmission for phototherapy compared with exclusively breastfed newborns (OR, 0.58; 95% CI, 0.47-0.72 for >0 to <2 formula feedings per day; OR, 0.24; 95% CI, 0.21-0.27 for ≥6 formula feedings per day). Subthreshold phototherapy was associated with a 22-hour longer length of stay (95% CI, 16-28 hours).

CONCLUSIONS AND RELEVANCE

Subthreshold phototherapy during the birth hospitalization is effective in preventing readmissions for phototherapy; however, for each readmission prevented, many newborns require phototherapy who would otherwise not need it.

Burden of severe neonatal jaundice: a systematic review and meta-analysis

CONTEXT

To assess the global burden of late and/or poor management of severe neonatal jaundice (SNJ), a common problem worldwide, which may result in death or irreversible brain damage with disabilities in survivors. Population-based data establishing the global burden of SNJ has not been previously reported.

OBJECTIVE

Determine the burden of SNJ in all WHO regions, as defined by clinical jaundice associated with clinical outcomes including acute bilirubin encephalopathy/kernicterus and/or exchange transfusion (ET) and/or jaundice-related death.

DATA SOURCES

PubMed, Scopus and other health databases were searched, without language restrictions, from 1990 to 2017 for studies reporting the incidence of SNJ.

STUDY SELECTION/DATA EXTRACTION

Stratification was performed for WHO regions and results were pooled using random effects model and meta-regression.

RESULTS

Of 416 articles including at least one marker of SNJ, only 21 reported estimates from population-based studies, with 76% (16/21) of them conducted in high-income countries. The African region has the highest incidence of SNJ per 10 000 live births at 667.8 (95% CI 603.4 to 738.5), followed by Southeast Asian, Eastern Mediterranean, Western Pacific, Americas and European regions at 251.3 (132.0 to 473.2), 165.7 (114.6 to 238.9), 9.4 (0.1 to 755.9), 4.4 (1.8 to 10.5) and 3.7 (1.7 to 8.0), respectively. The incidence of ET per 10 000 live births was significantly higher for Africa and Southeast Asian regions at 186.5 (153.2 to 226.8) and 107.1 (102.0 to 112.5) and lower in Eastern Mediterranean (17.8 (5.7 to 54.9)), Americas (0.38 (0.21 to 0.67)), European (0.35 (0.20 to 0.60)) and Western Pacific regions (0.19 (0.12 to 0.31). Only 2 studies provided estimates of clear jaundice-related deaths in infants with significant jaundice [UK (2.8%) and India (30.8%).

CONCLUSIONS

Limited but compelling evidence demonstrates that SNJ is associated with a significant health burden especially in low-income and middle-income countries.

Neonatal Jaundice in Low- and Middle-Income Countries: Lessons and Future Directions from the 2015 Don Ostrow Trieste Yellow Retreat

Severe neonatal hyperbilirubinemia, defined as total serum bilirubin (TSB) ≥20 mg/dl, is associated with a higher risk of permanent neurological sequelae and death. Jaundice can and should be promptly diagnosed and treated. Reliable methods for TSB assay are not always readily available, particularly in low- and middle-income countries, making the true incidence of severe neonatal jaundice (NNJ) difficult to estimate. To gather a more comprehensive picture, a symposium addressing NNJ worldwide was organized during the 2015 Don Ostrow Trieste Yellow Retreat. Data collected by several researchers in different regions of the world were presented and differences/similarities discussed. This report points out the need for: (1) a coordinated worldwide effort to define the burden and the causes of severe NNJ and its consequences; (2) aggressive educational programs for families and health personnel to facilitate timely care-seeking, and (3) accurate diagnostics and effective phototherapy.

Why is kernicterus still a major cause of death and disability in low-income and middle-income countries?

Neonatal jaundice is predominantly a benign condition that affects 60%-80% of newborns worldwide but progresses to potentially harmful severe hyperbilirubinaemia in some. Despite the proven therapeutic benefits of phototherapy for preventing extreme hyperbilirubinaemia, acute bilirubin encephalopathy or kernicterus, several low-income and middle-income countries (LMIC) continue to report high rates of avoidable exchange transfusions, as well as bilirubin-induced mortality and neurodevelopmental disorders. Considering the critical role of appropriate timing in treatment effectiveness, this review set out to examine the contributory factors to the burden of severe hyperbilirubinaemia and kernicterus based on the 'three delays model' described by Thaddeus and Maine in the 91 most economically disadvantaged LMICs with Gross National Income per capita ≤US$6000 and median human development index of 0.525 (IQR: 0.436-0.632). Strategies for addressing these delays are proposed including the need for clinical and public health leadership to curtail the risk and burden of kernicterus in LMICs.

Incidence, etiology, and outcomes of hazardous hyperbilirubinemia in newborns

BACKGROUND AND OBJECTIVES

Total serum bilirubin (TSB) levels ≥ 30 mg/dL are rare but potentially hazardous. A better understanding of their incidence, causes, and outcomes could help inform preventive efforts.

METHODS

We identified infants born ≥ 35 weeks' gestational age from 1995-2011 in Kaiser Permanente Northern California (n = 525409) and examined the medical records of infants with a TSB ≥ 30 mg/dL to determine etiology and the occurrence of acute bilirubin encephalopathy. We reviewed inpatient and outpatient encounters through 2013 for evidence of sensorineural hearing loss (SNHL) or cerebral palsy (CP).

RESULTS

We identified 47 infants with TSB ≥ 30 mg/dL (8.6 per 100000 births). In 44 infants (94%), the hyperbilirubinemia occurred after the initial birth hospitalization. The etiology was not identified in 33 (70%). Glucose-6-phosphate dehydrogenase (G6PD) activity was measured in only 25 (53%) of whom 10 (40%) were deficient. Four children had acute bilirubin encephalopathy of whom 2 developed both CP and SNHL, and 1 developed isolated SNHL. These 3 infants all had G6PD deficiency and TSB >40 mg/dL. One additional 35-week infant with TSB 38.2 mg/dL had SNHL.

CONCLUSIONS

Hazardous (≥ 30 mg/dL) hyperbilirubinemia is a rare event. No etiology could be identified from the clinical record in most cases. G6PD deficiency was the leading cause of hazardous hyperbilirubinemia when an etiology was identified, but many were not tested. Chronic, bilirubin-induced neurotoxicity was uncommon and occurred only in the setting of additional risk factors and TSB values well over (>15 mg/dL) the American Academy of Pediatrics exchange transfusion thresholds.

Severe neonatal hyperbilirubinemia leading to exchange transfusion

BACKGROUND

Severe neonatal hyperbilirubinemia is associated with significant morbidity and mortality. This study was conducted to investigate the causes of severe hyperbilirubinemia leading to Exchange Transfusion (ET) from March 2009 to March 2011 in Bahrami children hospital, Tehran, Iran in order to establish guidelines to prevent profound jaundice & ET.

METHODS

94 neonates underwent ET for severe hyperbilirubinemia data for demographic data, and onset of jaundice, history of severe hyperbilirubinemia in siblings, blood group of both mother and neonate, G6PD activity, hemoglobin, hematocrite, reticulocyte count, peripheral blood smear, total and direct bilirubin before and after ET, direct and indirect Coombs, times of transfusion and the cause of hyperbilirubinemia were all recorded for analysis.

RESULTS

Ninety four neonates (56.4% boys and 43.6% girls) underwent ET with a mean birth weight of 1950±40 g and a mean gestational age of 35.2±1.4 weeks. Premature labor, breastfeeding jaundice, ABO incompatibility and G6PDD with the frequency of 59(63%), 33(35%), 25(24/5%) and 12(12.8%) were of major causes of ET.

CONCLUSIONS

Predisposing factors for severe hyperbilirubinemia in this study were premature labor, breastfeeding jaundice, ABO incompatibility and G6PDD. The authors recommend prevention of premature labor, reevaluation of successful breastfeeding education for mothers and screening infants for blood group and G6PD In the first of life. Arranging earlier and continuous visits in neonates with these risk factors during the first four days of life is also recommended.

Comparison of two transcutaneous bilirubinometers in term and near-term neonates

PURPOSE

Determination of bilirubin levels is performed for many newborns in the first days of life, and several different transcutaneous bilirubinometers are available. We aimed to determine whether transcutaneous bilirubin measurement, as performed using Jaundice Detector JH20-1C, a new device, correlates with Minolta/Hill-Rom Air-Shields Transcutaneous Jaundice Meter model JM-103.

DESIGN AND SAMPLE

The study was performed on term or near-term newborn infants who underwent transcutaneous bilirubin measurements as part of their normal care. The study group consisted of 585 newborn infants with gestational ages ranging from 35 to 42 weeks, coming from an uneventful pregnancy. In this prospective study, bilirubin concentrations were determined with two different transcutaneous bilirubinometers.

MAIN OUTCOME VARIABLE

In 585 infants, the correlation coefficient for Jaundice Detector JH20-1C versus Minolta Air-Shields Jaundice Meter model JM-103 was .965 (p < .0001). The mean (± standard deviation) difference between the Jaundice Detector JH20-1C versus Minolta Air-Shields Jaundice Meter model JM-103 was 0.26 ± 0.95 mg/dL. Results showed the Jaundice Detector JH20-1C to have an acceptable level of intradevice imprecision (r = .978, p < .0001, mean differences .0158 ± .871 mg/dL).

RESULTS

Jaundice Detector JH20-1C showed the good performances of intradevice and interdevice imprecision in comparison with Minolta/Hill-Rom Air-Shields Transcutaneous Jaundice Meter model JM-103. Jaundice Detector JH20-1C may be suitable for screening term or near-term newborn infants for jaundice in the well-baby nursery or maternity ward.

Invited commentary: does neonatal hyperbilirubinemia cause asthma?

In an analysis of data from the US Collaborative Perinatal Project, Huang et al. (Am J Epidemiol. 2013;178(12):1691-1697) report an association between neonatal total serum bilirubin levels and childhood asthma. To consider the implications of this finding, we need to evaluate whether the association is causal. The results do not appear to be due to chance or any obvious biases. It is likely that the observed association is the result of a common cause of both hyperbilirubinemia and asthma (confounding). Polymorphisms in the glutathione S-transferase gene are a potential genetic confounder. The glutathione S-transferase M1-null phenotype has been linked to both neonatal hyperbilirubinemia and asthma in several studies. Before making any changes in practice aimed at lowering peak bilirubin levels to reduce asthma risk, it is vital to determine not only whether the association between higher bilirubin levels and asthma risk is causal, but also whether interventions to reduce peak bilirubin levels (or their duration) are associated with decreased risk of asthma (without evidence of other adverse effects). The study by Huang et al. should encourage further investigation of these questions.

Hospital readmissions and emergency department visits in moderate preterm, late preterm, and early term infants

The increased vulnerability of late preterm infants is no longer a novel concept in neonatology, with many studies documenting excess morbidity and mortality in these infants during the birth hospitalization. Because outcomes related to gestational age constitute a continuum, it is important to analyze data from the gestational age groups that bookend late preterm infants infants-moderate preterm infants (31-32 weeks) and early term infants (37-38 weeks). This article evaluates hospital readmissions and emergency department visits in the first 30 days after discharge from birth hospitalization in a large cohort of infants greater than or equal to 31 weeks' gestation.

Applying data mining techniques to improve diagnosis in neonatal jaundice

Background

Hyperbilirubinemia is emerging as an increasingly common problem in newborns due to a decreasing hospital length of stay after birth. Jaundice is the most common disease of the newborn and although being benign in most cases it can lead to severe neurological consequences if poorly evaluated. In different areas of medicine, data mining has contributed to improve the results obtained with other methodologies.

Hence, the aim of this study was to improve the diagnosis of neonatal jaundice with the application of data mining techniques.

Methods

This study followed the different phases of the Cross Industry Standard Process for Data Mining model as its methodology.

This observational study was performed at the Obstetrics Department of a central hospital (Centro Hospitalar Tâmega e Sousa – EPE), from February to March of 2011. A total of 227 healthy newborn infants with 35 or more weeks of gestation were enrolled in the study. Over 70 variables were collected and analyzed. Also, transcutaneous bilirubin levels were measured from birth to hospital discharge with maximum time intervals of 8 hours between measurements, using a noninvasive bilirubinometer.

Different attribute subsets were used to train and test classification models using algorithms included in Weka data mining software, such as decision trees (J48) and neural networks (multilayer perceptron). The accuracy results were compared with the traditional methods for prediction of hyperbilirubinemia.

Results

The application of different classification algorithms to the collected data allowed predicting subsequent hyperbilirubinemia with high accuracy. In particular, at 24 hours of life of newborns, the accuracy for the prediction of hyperbilirubinemia was 89%. The best results were obtained using the following algorithms: naive Bayes, multilayer perceptron and simple logistic.

Conclusions

The findings of our study sustain that, new approaches, such as data mining, may support medical decision, contributing to improve diagnosis in neonatal jaundice.

Trends of transcutaneous bilirubin in neonates who develop significant hyperbilirubinemia

OBJECTIVES

To provide data on the natural course of transcutaneous bilirubin (TcB) levels in neonates before the development of significant hyperbilirubinemia, and to assess the effect of different demographic and perinatal factors on the rate of TcB increase.

METHODS

We analyzed 2454 TcB measurements from 419 neonates before the development of significant hyperbilirubinemia. Mean TcB values and TcB percentiles for designated times were calculated, and the effect of different risk factors on the rate of TcB increase was assessed. TcB percentile curves were plotted for comparison on a population-based TcB nomogram.

RESULTS

Blood incompatibilities and glucose-6-phosphate dehy-drogenase deficiency were associated with higher rates of TcB in-crease during the first 36 to 48 postnatal hours, whereas smaller gestational age, increased weight loss, and exclusive breastfeeding had a similar but later effect. Compared with general population norms, a different pattern of TcB increase was noted in neonates who developed significant hyperbilirubinemia, but with a sub-stantial overlap of TcB values during the first 24 to 48 postnatal hours.

CONCLUSIONS

We provide data on the natural course of TcB levels before the development of significant hyperbilirubinemia in a white population of term and near-term neonates. Smaller gestational age, blood incompatibilities, glucose-6-phosphate dehydrogenase deficiency, increased weight loss, and exclusive breastfeeding significantly affected the rate of TcB increase in a time-dependent manner. These findings may assist in assessing the risk for significant hyperbilirubinemia and planning appropriate follow-up strategies for neonates with borderline bilirubin levels.

Total serum bilirubin exceeding exchange transfusion thresholds in the setting of universal screening

OBJECTIVE

To describe the incidence and predictors of total serum bilirubin (TSB) levels that meet or exceed American Academy of Pediatrics (AAP) exchange transfusion (ET) thresholds in the setting of universal screening.

STUDY DESIGN

We conducted a retrospective cohort analysis of electronic data on 18 089 newborns ≥35 weeks gestation born at Northern California Kaiser Permanente Medical Care Program hospitals implementing universal TSB screening in 2005 to 2007, with chart review for subjects with TSB levels reaching the AAP threshold for ET.

RESULTS

The outcome developed in 22 infants (0.12%); 14 (63.6%) were <38 weeks gestation. Only one infant received an ET; none of the infants had documented sequelae. The first TSB was at least high-intermediate risk on the AAP risk-nomogram for all 22 infants and high-risk for those ≥38 weeks, but was less than the phototherapy level in 15 infants (68%). Of these 15 infants, 2 failed phototherapy and 13 did not have a TSB repeated in <24 hours. However, re-testing all infants at high-intermediate risk or greater would have required 2166 additional bilirubin tests.

CONCLUSION

Screening was sensitive but not specific for predicting exchange threshold.

Efficacy of phototherapy for newborns with hyperbilirubinemia: a cautionary example of an instrumental variable analysis

BACKGROUND

Use of instrumental variables is gaining popularity as a method of controlling for confounding by indication in observational studies of treatments.

OBJECTIVES

To illustrate how unmeasured instrument-level treatment substitution can distort effect size estimates using as an example an instrumental variable analysis of phototherapy for neonatal jaundice.

DESIGN

Retrospective cohort study.

SETTING

Northern California Kaiser Permanente Hospitals.

PATIENTS

The authors studied 20,731 newborns ≥ 2000 g and ≥ 35 weeks' gestation born 1995-2004 with a "qualifying" total serum bilirubin (TSB) level within 3 mg/dL of the 2004 American Academy of Pediatrics (AAP) phototherapy threshold who did not have a positive direct antiglobulin test.

MEASUREMENTS

The intervention was inpatient phototherapy within 8 hours of the qualifying TSB. The outcome was a TSB level exceeding the AAP exchange transfusion threshold <48 hours from the qualifying TSB. The instrumental variable was a measure of the frequency of phototherapy use at the newborn's birth hospital. The unmeasured substituted treatment was supplementation with infant formula, assessed by chart review in a sample from the same cohort.

RESULTS

In total, 128 infants (0.62%) exceeded the exchange transfusion threshold. Logistic and propensity analyses yielded crude odds ratios of ~0.5 for phototherapy efficacy, decreasing to ~0.2 with control for confounding by indication. Instrumental variable analyses suggested much greater phototherapy efficacy (e.g., odds ratios of 0.02-0.05). However, chart reviews revealed greater use of infant formula (which also lowers bilirubin levels) in hospitals that used more phototherapy (r = 0.56; P = 0.02), an association not present at the individual level (r = 0.13).

CONCLUSIONS

Instrumental variable analyses may provide biased estimates of treatment efficacy if there are cointerventions or confounders associated with treatment at the level of the instrument, although even when these associations may not exist in individuals.

Assessing jaundice in infants of 35-week gestation and greater

PURPOSE OF REVIEW

In 2004, the American Academy of Pediatrics officially recommended universal predischarge risk assessment for severe neonatal hyperbilirubinemia with the goal of minimizing subsequent risk of chronic bilirubin encephalopathy (formerly known as kernicterus). In this article, we review recent research regarding jaundice predischarge risk assessment, current expert recommendations for universal predischarge bilirubin screening, and concerns expressed in the literature regarding these recommendations.

RECENT FINDINGS

A group of experts have recently recommended universal predischarge bilirubin screening to identify newborns at risk for developing severe neonatal hyperbilirubinemia. In contrast, the United States Preventive Services Task Force states that there is insufficient evidence to make this recommendation. Transcutaneous bilirubinometry has emerged as a noninvasive, quick method to screen for neonatal hyperbilirubinemia, although refinement and validation of transcutaneous bilirubin nomograms are needed. Newer studies suggest that the combined use of a predischarge bilirubin and gestational age risk assessment offers a simple, objective, and accurate way to identify infants at risk for subsequent, severe hyperbilirubinemia.

SUMMARY

All newborns should be systematically assessed for risk of developing severe hyperbilirubinemia prior to hospital discharge. Although limited data exist to recommend its use universally, predischarge bilirubin screening should be considered given recent expert opinion. The role of transcutaneous bilirubinometry remains promising, although further research evaluating and validating its use in varied and diverse populations is imperative. Combined models of risk assessment may offer the best approach to identifying infants at risk for subsequent, severe hyperbilirubinemia.

Significant weight loss in breastfed term infants readmitted for hyperbilirubinemia

Background

Weight loss of greater than 7% from birth weight indicates possible feeding problems. Inadequate oral intake causes weight loss and increases the bilirubin enterohepatic circulation. The objective of this study was to describe the association between total serum bilirubin (TSB) levels and weight loss in healthy term infants readmitted for hyperbilirubinemia after birth hospitalization.

Methods

We reviewed medical records of breastfed term infants who received phototherapy according to TSB levels readmitted to Caja Petrolera de Salud Clinic in La Paz, Bolivia during January 2005 through October 2008.

Results

Seventy-nine infants were studied (64.6% were males). The hyperbilirubinemia readmission rate was 5% among breastfed infants. Term infants were readmitted at a median age of 4 days. Mean TSB level was 18.6 ± 3 mg/dL. Thirty (38%) had significant weight loss. A weak correlation between TSB levels and percent of weight loss was identified (r = 0.20; p < 0.05). The frequency of severe hyperbilirubinemia (> 20 mg/dL) was notably higher among infants with significant weight loss (46.7% vs. 18.4%; p < 0.05). The risk of having severe hyperbilirubinemia was approximately 4 times greater for infants with significant weight loss (OR: 3.9; 95% CI: 1.4-10.8; p < 0.05).

Conclusions

Significant weight loss could be a useful parameter to identify breastfed term infants at risk of severe hyperbilirubinemia either during birth hospitalization or outpatient follow-up visits in settings where routine pre-discharge TSB levels have not been implemented yet.

Impact of universal bilirubin screening on severe hyperbilirubinemia and phototherapy use

OBJECTIVE

The goal was to assess the impact of universal bilirubin screening on severe hyperbilirubinemia and phototherapy use.

METHODS

In this retrospective cohort study of 358086 infants of > or =35 weeks and > or =2000 g born between January 1, 1995, and June 30, 2007, we obtained demographic data, bilirubin levels, and codes for inpatient phototherapy from existing databases. We compared the incidence of high total serum bilirubin (TSB) levels and phototherapy before and after implementation of universal screening and examined risk factors for high TSB levels.

RESULTS

A total of 38182 infants (10.6%) were born at facilities that had implemented universal bilirubin screening. Compared with infants born at facilities that were not screening, these infants had a 62% lower incidence of TSB levels exceeding the American Academy of Pediatrics exchange guideline (0.17% vs 0.45%; P < .001), received twice the inpatient phototherapy (9.1% vs 4.2%; P < .001), and had slightly longer birth hospitalization lengths of stay (50.9 vs 48.7 hours; P < .001). Of those receiving phototherapy, 56% after initiation of universal screening had TSB levels at which phototherapy was recommended by the guideline, compared with 70% before screening. The adjusted odds ratio for developing TSB levels exceeding the guideline value was 0.28 (95% confidence interval: 0.20-0.40) for those born at a facility using TSB screening and 0.28 (95% confidence interval: 0.19-0.42) for those born at a facility using transcutaneous bilirubin screening.

CONCLUSIONS

Universal bilirubin screening was associated with a significantly lower incidence of severe hyperbilirubinemia but also with increased phototherapy use.

Numbers needed to treat with phototherapy according to American Academy of Pediatrics guidelines

OBJECTIVES

Our aims were to estimate the efficacy of hospital phototherapy for neonatal jaundice and the number needed to treat to prevent one infant from reaching the exchange transfusion level.

METHODS

From a cohort of 281 898 infants weighing > or =2000 g born at > or =35 weeks' gestation at 12 Northern California Kaiser hospitals from 1995 to 2004, we identified 22 547 who had a "qualifying total serum bilirubin level" within 3 mg/dL of the American Academy of Pediatrics 2004 guideline phototherapy threshold. We used multiple logistic regression to estimate the efficacy of hospital phototherapy within 8 hours at preventing the bilirubin level from exceeding the 2004 guideline's exchange transfusion threshold within 48 hours. We combined this efficacy estimate with other predictors of risk to estimate the numbers needed to treat at different values of covariates.

RESULTS

Of the 22 547 eligible newborns, 5251 (23%) received hospital phototherapy within 8 hours of their qualifying bilirubin level. Only 354 (1.6%) ever exceeded the guideline exchange transfusion threshold; 187 (0.8%) did so within 48 hours. Among infants who did not have a positive direct antiglobulin test, hospital phototherapy within 8 hours was highly effective (adjusted odds ratio, 0.16; 95% confidence interval, 0.07-0.34). For infants with bilirubin levels 0-0.9 mg/dL above the phototherapy threshold, the estimated number needed to treat at mean values of covariates was 222 (95% CI: 107-502) for boys and 339 (95% CI: 154-729) for girls, ranging from 10 (95% CI: 6-19) for <24-hour-old, 36-week gestation boys to 3,041 (95% CI: 888-11 096) for > or =3-day-old 41-week girls. Hospital phototherapy was less effective for infants direct antiglobulin test-positive infants (adjusted odds ratio 0.55; 95% CI: 0.21-1.45; P = 0.01 for the direct antiglobulin test x phototherapy interaction).

CONCLUSIONS

While hospital phototherapy is effective, the number needed to treat according to current guidelines varies considerably across different infant subgroups.