Risk for cerebral palsy in infants with total serum bilirubin levels at or above the exchange transfusion threshold: a population-based study

IMPORTANCE

Exchange transfusion is recommended for newborns with total serum bilirubin (TSB) levels thought to place them at risk for cerebral palsy (CP). However, the excess risk for CP among these infants is unknown.

OBJECTIVE

To quantify the risks for CP and CP consistent with kernicterus that are associated with high TSB levels based on the 2004 American Academy of Pediatrics exchange transfusion threshold (ETT) guidelines.

DESIGN, SETTING, AND PARTICIPANTS

We enrolled 2 cohorts from a population of 525,409 infants in the Late Impact of Getting Hyperbilirubinemia or Phototherapy (LIGHT) birth cohort. Eligible infants were born at a gestational age of at least 35 weeks at 15 hospitals within the Kaiser Permanente Northern California integrated medical care delivery system from January 1, 1995, through December 31, 2011.

EXPOSURES

The exposed cohort included all 1833 infants with at least 1 TSB measurement at or above the ETT based on age at testing, gestational age, and results of direct antiglobulin testing. The unexposed cohort was a 20% random sample of 104 716 infants with TSB levels below the ETT.

MAIN OUTCOMES AND MEASURES

A pediatric neurologist blinded to the TSB levels reviewed medical records to determine the presence of CP, defined as a nonprogressive congenital motor dysfunction with hypertonia or dyskinesia. Cerebral palsy was judged to be consistent with kernicterus if magnetic resonance imaging of the brain revealed bilateral globus pallidus injury in the setting of dyskinetic CP.

RESULTS

We identified CP in 7 of 1833 exposed (0.4%) vs 86 of 104 716 unexposed (0.1%) infants (relative risk, 4.7 [95% CI, 2.2-10.0]). Absolute risk differences were 0.2% (95% CI, 0%-0.5%) for a TSB level 0 to 4.9 mg/dL above the ETT (n = 1705), 0.9% (95% CI, 0.1%-5.3%) for a TSB level 5.0 to 9.9 mg/dL above the ETT (n = 102), and 7.6% (95% CI, 2.1%-24.1%) for a TSB level 10 mg/dL or more above the ETT (n = 26). Cerebral palsy consistent with kernicterus occurred in 3 infants (incidence, 0.57 per 100,000 births); all 3 had TSB levels of more than 5.0 mg/dL above the ETT and at least 2 risk factors for neurotoxicity, such as prematurity, glucose-6-phosphate dehydrogenase deficiency, or hypoxia-ischemia.

CONCLUSIONS AND RELEVANCE

Cerebral palsy consistent with kernicterus occurred only in infants with 2 or more risk factors for neurotoxicity and TSB levels of more than 5 mg/dL above the ETT. Among infants with lower degrees of TSB level elevation, the excess risk for CP is minimal.

Care practices and traditional beliefs related to neonatal jaundice in northern Vietnam: a population-based, cross-sectional descriptive study

BACKGROUND

The National Hospital of Pediatrics in Vietnam performed >200 exchange transfusions annually (2006-08), often on infants presenting encephalopathic from lower-level hospitals. As factors delaying care-seeking are not known, we sought to study care practices and traditional beliefs relating to neonatal jaundice in northern Vietnam.

METHODS

We conducted a prospective, cross-sectional, population-based, descriptive study from November 2008 through February 2010. We prospectively identified mothers of newborns through an on-going regional cohort study. Trained research assistants administered a 78-item questionnaire to mothers during home visits 14-28 days after birth except those we could not contact or whose babies remained hospitalized at 28 days.

RESULTS

We enrolled 979 mothers; 99% delivered at a health facility. Infants were discharged at a median age of 1.35 days. Only 11% received jaundice education; only 27% thought jaundice could be harmful. During the first week, 77% of newborns were kept in dark rooms. Only 2.5% had routine follow-up before 14 days. Among 118 mothers who were worried by their infant's jaundice but did not seek care, 40% held non-medical beliefs about its cause or used traditional therapies instead of seeking care. Phototherapy was uncommon: 6 (0.6%) were treated before discharge and 3 (0.3%) on readmission. However, there were no exchange transfusions, kernicterus cases, or deaths.

CONCLUSIONS

Early discharge without follow-up, low maternal knowledge, cultural practices, and use of traditional treatments may limit or delay detection or care-seeking for jaundice. However, in spite of the high prevalence of these practices and the low frequency of treatment, no bad outcomes were seen in this study of nearly 1,000 newborns.

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.

Stratification of risk of early-onset sepsis in newborns ≥ 34 weeks' gestation

OBJECTIVE

To define a quantitative stratification algorithm for the risk of early-onset sepsis (EOS) in newborns ≥ 34 weeks' gestation.

METHODS

We conducted a retrospective nested case-control study that used split validation. Data collected on each infant included sepsis risk at birth based on objective maternal factors, demographics, specific clinical milestones, and vital signs during the first 24 hours after birth. Using a combination of recursive partitioning and logistic regression, we developed a risk classification scheme for EOS on the derivation dataset. This scheme was then applied to the validation dataset.

RESULTS

Using a base population of 608,014 live births ≥ 34 weeks' gestation at 14 hospitals between 1993 and 2007, we identified all 350 EOS cases <72 hours of age and frequency matched them by hospital and year of birth to 1063 controls. Using maternal and neonatal data, we defined a risk stratification scheme that divided the neonatal population into 3 groups: treat empirically (4.1% of all live births, 60.8% of all EOS cases, sepsis incidence of 8.4/1000 live births), observe and evaluate (11.1% of births, 23.4% of cases, 1.2/1000), and continued observation (84.8% of births, 15.7% of cases, incidence 0.11/1000).

CONCLUSIONS

It is possible to combine objective maternal data with evolving objective neonatal clinical findings to define more efficient strategies for the evaluation and treatment of EOS in term and late preterm infants. Judicious application of our scheme could result in decreased antibiotic treatment in 80,000 to 240,000 US newborns each year.

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.

First-day weight loss predicts eventual weight nadir for breastfeeding newborns

OBJECTIVE

To examine the relationship between high (≥5%) weight loss during the first 24 h after birth and eventual excess weight loss (EWL) of ≥10% of birth weight.

DESIGN

Retrospective cohort study.

SETTING

Kaiser Permanente Northern California hospitals.

PATIENTS

63 096 infants born at ≥36 weeks in 2009-2010, of whom 59 761 (94.5%) had a weight subsequent to birth weight measured at <24 h.

MAIN PREDICTOR MEASURE

Per cent of birth weight lost by 24 h of age.

MAIN OUTCOME MEASURE

Weight nadir, defined as the lowest recorded inpatient or outpatient weight in the first 30 days after birth, expressed as a percentage of birth weight.

RESULTS

Among infants who breastfed at least once, mean (±SD) weight nadir was 6.3±3.5% below birth weight, and 9.6% of the newborns lost ≥10% of birth weight. Among 2670 infants who lost ≥5% of their birth weight in the first 24 h, 782 (29%) eventually developed EWL, compared with 4840 (8%) of 57 109 infants who lost <5% (p<0.0005). In multivariate analysis, ≥5% first-day weight loss predicted eventual EWL (≥10%) with an OR of 4.06 (95% CI 3.69 to 4.46) after adjusting for gestational age, method of delivery, maternal race/ethnicity and hospital of birth.

CONCLUSIONS

High first-day weight loss predicts eventual weight nadir and can be used to identify infants who might benefit from targeted interventions to support breastfeeding and prevent EWL.

Understanding the direction of bias in studies of diagnostic test accuracy

Ordering and interpreting diagnostic tests is a critical part of emergency medicine (EM). In evaluating a study of diagnostic test accuracy, emergency physicians (EPs) need to recognize whether the study uses case-control or cross-sectional sampling and account for common biases. The authors group biases in studies of test accuracy into five categories: incorporation bias, partial verification bias, differential verification bias, imperfect gold standard bias, and spectrum bias. Other named biases are either equivalent to these biases or subtypes within these broader categories. The authors go beyond identifying a bias and predict the direction of its effect on sensitivity and specificity, providing numerical examples from published test accuracy studies. Understanding the direction of a bias may permit useful inferences from even a flawed study of test accuracy.

Maternal diagnosis of obesity and risk of cerebral palsy in the child

OBJECTIVE

To examine the association between maternal hospital diagnoses of obesity and risk of cerebral palsy (CP) in the child.

STUDY DESIGN

For all California hospital births from 1991-2001, we linked infant and maternal hospitalization discharge abstracts to California Department of Developmental Services records of children receiving services for CP. We identified maternal hospital discharge diagnoses of obesity (International Classification of Diseases, 9th edition 646.1, 278.00, or 278.01) and morbid obesity (International Classification of Diseases, 9th edition 278.01), and performed logistic regression to explore the relationship between maternal obesity diagnoses and CP.

RESULTS

Among 6.2 million births, 67 200 (1.1%) mothers were diagnosed with obesity, and 7878 (0.1%) with morbid obesity; 8798 (0.14%) children had CP. A maternal diagnosis of obesity (relative risk [RR] 1.30, 95% CI 1.09-1.55) or morbid obesity (RR 2.70, 95% CI 1.89-3.86) was associated with increased risk of CP. In multivariable analysis adjusting for maternal race, age, education, prenatal care, insurance status, and infant sex, both obesity (OR 1.27, 95% CI 1.06-1.52) and morbid obesity (OR 2.56, 95% CI 1.79-3.66) remained independently associated with CP. On stratified analyses, the association of obesity (RR 1.72, 95% CI 1.25-2.35) or morbid obesity (RR 3.79, 95% CI 2.35-6.10) with CP was only significant among women who were hospitalized prior to the birth admission. Adjusting for potential comorbidities and complications of obesity did not eliminate this association.

CONCLUSIONS

Maternal obesity may confer an increased risk of CP in some cases. Further studies are needed to confirm this finding.

Effect of early limited formula on duration and exclusivity of breastfeeding in at-risk infants: an RCT

BACKGROUND AND OBJECTIVES

Recent public health efforts focus on reducing formula use for breastfed infants during the birth hospitalization. No previous randomized trials report the effects of brief early formula use. The objective of the study was to determine if small formula volumes before the onset of mature milk production might reduce formula use at 1 week and improve breastfeeding at 3 months for newborns at risk for breastfeeding problems.

METHODS

We randomly assigned 40 exclusively breastfeeding term infants, 24 to 48 hours old, who had lost ≥5% birth weight to early limited formula (ELF) intervention (10 mL formula by syringe after each breastfeeding and discontinued when mature milk production began) or control (continued exclusive breastfeeding). Our outcomes were breastfeeding and formula use at 1 week and 1, 2, and 3 months.

RESULTS

Among infants randomly assigned to ELF during the birth hospitalization, 2 (10%) of 20 used formula at 1 week of age, compared with 9 (47%) of 19 control infants assigned during the birth hospitalization to continue exclusive breastfeeding (P = .01). At 3 months, 15 (79%) of 19 infants assigned to ELF during the birth hospitalization were breastfeeding exclusively, compared with 8 (42%) of 19 controls (P = .02).

CONCLUSIONS

Early limited formula may reduce longer-term formula use at 1 week and increase breastfeeding at 3 months for some infants. ELF may be a successful temporary coping strategy for mothers to support breastfeeding newborns with early weight loss. ELF has the potential for increasing rates of longer-term breastfeeding without supplementation based on findings from this RCT.

Black race is not protective against hazardous bilirubin levels

Although black race is considered protective against hyperbilirubinemia, black infants appear at increased risk of kernicterus. We found that although black infants have a lower risk of developing total serum bilirubin levels ≥ 20 mg/dL than white infants, they appear at greater risk of developing levels ≥ 30 mg/dL.

Evidence basis for individualized evaluation and less imaging in febrile urinary tract infection: an editorial commentary

The past decade has seen a remarkable retreat from previous dogma regarding urinary tract infections (UTIs). Less aggressive imaging is now recommended because although vesicoureteral reflux (VUR) is frequently found in children with a history of febrile UTIs, most VUR resolves spontaneously and we do not have evidence that treatment of the rest improves outcome. Available evidence suggests urine testing for UTI can be less aggressive as well, focusing on those with the most risk factors for UTI, those with the most severe illness, and those at highest risk of complications.

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.

Cerebral palsy among Asian ethnic subgroups

OBJECTIVE

Asians have a reduced risk for cerebral palsy (CP) compared with whites. We examined whether individual Asian subgroups have a reduced risk of CP and whether differences in sociodemographic factors explain disparities in CP prevalence.

METHODS

In a retrospective cohort of 629 542 Asian and 2 109 550 white births in California from 1991 to 2001, we identified all children who qualified for services from the California Department of Health Services on the basis of CP. Asians were categorized as East Asian (Chinese, Japanese, Koreans), Filipino, Indian, Pacific Islander (Guamanians, Hawaiians, and Pacific Islanders), Samoan, or Southeast Asian (Cambodian, Laotian, Thai, Vietnamese).

RESULTS

Overall, CP prevalence was lower in Asians than whites (1.09 vs 1.36 per 1000; relative risk = 0.80, 95% confidence interval [CI] = 0.74-0.87) and ranged from 0.61/1000 in Thai children to 2.08/1000 in Samoan children. Several Asian subgroups had low risk profiles with respect to maternal age, educational attainment, and birth weight. However, after we adjusted for maternal age and education, infant gender, and birth weight, the adjusted risk of CP remained lower in East Asians (odds ratio [OR] = 0.75, 95% CI = 0.65-0.87), Filipinos (OR = 0.87, 95% CI = 0.75-0.99), Indians (OR = 0.59, 95% CI = 0.44-0.80), Pacific Islanders (OR = 0.62, 95% CI = 0.40-0.97), and Southeast Asians (OR = 0.68, 95% CI = 0.57-0.82) compared with whites.

CONCLUSIONS

Most Asian national origin subgroups have a lower rate of CP than whites, and this disparity is unexplained. Additional studies that focus on the cause of ethnic disparities in CP may provide new insights into pathogenesis and prevention.

Randomised trial comparing hand expression with breast pumping for mothers of term newborns feeding poorly

OBJECTIVE

Breast pumping or hand expression may be recommended when newborns latch or suck poorly. A recent trial found worse outcomes among mothers who used a breast pump in the early postpartum period. The objective of this study was to compare bilateral electric breast pumping to hand expression among mothers of healthy term infants feeding poorly at 12-36 h after birth.

DESIGN

Randomised controlled trial.

SETTING

Well-baby nursery and postpartum unit.

PATIENTS

68 mothers of newborns 12-36 h old who were latching or sucking poorly were randomly assigned to either 15 min of bilateral electric pumping or 15 min of hand expression.

MAIN OUTCOME MEASURES

Milk transfer, maternal pain, breastfeeding confidence and breast milk expression experience (BMEE) immediately after the intervention, and breastfeeding rates at 2 months after birth.

RESULTS

The median volume of expressed milk (range) was 0.5 (0-5) ml for hand expressing mothers and 1 (0-40) ml for pumping mothers (p=0.07). Maternal pain, breastfeeding confidence and BMEE did not differ by intervention. At 2 months, mothers assigned to hand expression were more likely to be breastfeeding (96.1%) than mothers assigned to breast pumping (72.7%) (p=0.02).

CONCLUSIONS

Hand expression in the early postpartum period appears to improve eventual breastfeeding rates at 2 months after birth compared with breast pumping, but further research is needed to confirm this. However, in circumstances where either pumping or hand expression would be appropriate for healthy term infants 12-36 h old feeding poorly, providers should consider recommending hand expression.

Estimating the probability of neonatal early-onset infection on the basis of maternal risk factors

OBJECTIVE

To develop a quantitative model to estimate the probability of neonatal early-onset bacterial infection on the basis of maternal intrapartum risk factors.

METHODS

This was a nested case-control study of infants born at ≥34 weeks' gestation at 14 California and Massachusetts hospitals from 1993 to 2007. Case-subjects had culture-confirmed bacterial infection at <72 hours; controls were randomly selected, frequency-matched 3:1 according to year and birth hospital. We performed multivariate analyses and split validation to define a predictive model based only on information available in the immediate perinatal period.

RESULTS

We identified 350 case-subjects from a cohort of 608,014 live births. Highest intrapartum maternal temperature revealed a linear relationship with risk of infection below 100.5°F, above which the risk rose rapidly. Duration of rupture of membranes revealed a steadily increasing relationship with infection risk. Increased risk was associated with both late-preterm and postterm delivery. Risk associated with maternal group B Streptococcus colonization is diminished in the era of group B Streptococcus prophylaxis. Any form of intrapartum antibiotic given >4 hours before delivery was associated with decreased risk. Our model showed good discrimination and calibration (c statistic = 0.800 and Hosmer-Lemeshow P = .142 in the entire data set).

CONCLUSIONS

A predictive model based on information available in the immediate perinatal period performs better than algorithms based on risk-factor threshold values. This model establishes a prior probability for newborn sepsis, which could be combined with neonatal physical examination and laboratory values to establish a posterior probability to guide treatment decisions.

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.

Evidence suggests there was not a "resurgence" of kernicterus in the 1990s

BACKGROUND

Although some have suggested that kernicterus disappeared in the United States in the 1970s to 1980s and dramatically reappeared in the 1990s, population-based data to support such a resurgence are lacking.

METHODS

We used diagnosis codes on data collection forms from the California Department of Developmental Services (DDS) to identify kernicterus cases among children born from 1988 to 1997. We examined kernicterus mortality trends in the United States from 1979 to 2006 using death certificate data from the National Center for Health Statistics.

RESULTS

We identified 25 cases of physician-diagnosed kernicterus. This figure was augmented to reflect estimates of cases lost to infant mortality, yielding incidence estimates of 1 in 200 000 California live births, 1 in 2500 among children who received services from DDS, and 1 in 400 children with cerebral palsy. There was no significant trend in kernicterus incidence from 1988 to 1997 (P = .77). Incidence before and after the 1994 publication of the AAP practice parameter for hyperbilirubinemia in healthy term infants was not significantly different (P = .92). Nationally, there were 3 reported infant deaths from kernicterus in 1994 and 2 or fewer in the other 28 years from 1979 to 2006 (0.28 deaths per million live births): there was no significant increase in kernicterus mortality over this period.

CONCLUSION

Data from California do not support a resurgence of kernicterus in the 1990s. Deaths from kernicterus in the United States have remained rare, with no apparent increase during the last 25 years.

Does this coughing adolescent or adult patient have pertussis?

CONTEXT

Pertussis is often overlooked as a cause of chronic cough, especially in adolescents and adults. Several symptoms are classically thought to be suggestive of pertussis, but the diagnostic value of each of them is uncertain.

OBJECTIVE

To systematically review the evidence regarding the diagnostic value of 3 classically described symptoms of pertussis: paroxysmal cough, posttussive emesis, and inspiratory whoop.

DATA SOURCES, STUDY SELECTION, AND DATA EXTRACTION

We searched MEDLINE (January 1966-April 2010), EMBASE (January 1969 to April 2010), and the bibliographies of pertinent articles to identify relevant English-language studies. Articles were selected that included children older than 5 years, adolescents, or adults and confirmed the diagnosis of pertussis among patients with cough illness (of any duration) with an a priori-defined accepted reference standard. Two authors independently extracted data from articles that met selection criteria and resolved any discrepancies by consensus.

DATA SYNTHESIS

Five prospective studies met inclusion criteria; 3 were used in the analysis. Presence of posttussive emesis (summary likelihood ratio [LR], 1.8; 95% confidence interval [CI], 1.4-2.2) or inspiratory whoop (summary LR, 1.9; 95% CI, 1.4-2.6) increases the likelihood of pertussis. Absence of paroxysmal cough (summary LR, 0.52; 95% CI, 0.27-1.0) or posttussive emesis (summary LR, 0.58; 95% CI, 0.44-0.77) reduced the likelihood. Absence of inspiratory whoop was less useful (summary LR, 0.78; 95% CI, 0.66-0.93). No studies evaluated combinations of findings.

CONCLUSIONS

In a nonoutbreak setting, data to determine the diagnostic usefulness of symptoms classically associated with pertussis are limited and of relatively weak quality. The presence or absence of posttussive emesis or inspiratory whoop modestly change the likelihood of pertussis; therefore, clinicians must use their overall clinical impression to decide about additional testing or empirical treatment.

First-day newborn weight loss predicts in-hospital weight nadir for breastfeeding infants

BACKGROUND

Exclusive breastfeeding reduces infant infectious disease. Losing > or =10% birth weight may lead to formula use. The predictive value of first-day weight loss for subsequent weight loss has not been studied. The objective of the present study was to evaluate the relationship between weight loss at <24 hours and subsequent in-hospital weight loss > or =10%.

METHODS

For 1,049 infants, we extracted gestational age, gender, delivery method, feeding type, and weights from medical records. Weight nadir was defined as the lowest weight recorded during birth hospitalization. We used multivariate logistic regression to assess the effect of first-day weight loss on subsequent in-hospital weight loss.

RESULTS

Mean in-hospital weight nadir was 6.0 +/- 2.6%, and mean age at in-hospital weight nadir was 38.7 +/- 18.5 hours. While in the hospital 6.4% of infants lost > or =10% of birth weight. Infants losing > or =4.5% birth weight at <24 hours had greater risk of eventual in-hospital weight loss > or =10% (adjusted odds ratio 3.57 [1.75, 7.28]). In this cohort, 798 (76.1%) infants did not have documented weight gain while in the hospital.

CONCLUSIONS

Early weight loss predicts higher risk of > or =10% in-hospital weight loss. Infants with high first-day weight loss could be targeted for further research into improved interventions to promote breastfeeding.

Effect of neonatal jaundice and phototherapy on the frequency of first-year outpatient visits

OBJECTIVE

The objective of this study was to determine whether either hyperbilirubinemia or inpatient phototherapy is associated with increased subsequent outpatient visit rates, a possible effect of the "vulnerable child syndrome."

METHODS

We compared 3 groups of otherwise well term and late-preterm infants who were born between 1995 and 2004 in Northern California Kaiser hospitals: group 1 never had a documented total serum bilirubin (TSB) level > or =12 mg/dL (n = 128 417); group 2 had a TSB level > or =17 and <23 mg/dL as outpatients between 48 hours and 7 days of age and did not receive inpatient phototherapy (n = 6777); and group 3 met criteria for group 2 but did receive inpatient phototherapy (n = 1765). We compared outpatient visit rates from 15 to 364 days of age adjusting for other predictors of visit rates by using Poisson and linear regression.

RESULTS

The mean total number of visits between 15 and 364 days was 9.83. Compared with group 1, adjusted total first-year visit rates were slightly increased in group 2 (adjusted incidence rate ratio: 1.04 [95% confidence interval: 1.02-1.05]) and group 3 (incidence rate ratio: 1.07 [95% confidence interval: 1.05-1.10]). The increases in visit rates were greatest for visits from 15 to 59 days of age, for specialty visits, and for unspecified diagnoses. These rates correspond to adjusted increases in total first-year visits (compared with group 1) of 0.36 visits in group 2 and 0.73 visits in group 3.

CONCLUSIONS

Neonatal jaundice and inpatient phototherapy are associated with only small increases in first-year outpatient visit rates, consistent with mild or infrequent contribution to the vulnerable child syndrome in this population.

After-school program to reduce obesity in minority children: a pilot study

This study explored a community-based after-school program's effect on obesity in minority children. Study participants included 178 third through fifth graders (47% Latino, 25% Asian, and 18% African-American) enrolled in America SCORES Bay Area. Outcomes were attendance, change in fitness (20-meter shuttle test), and body mass index (BMI) z-score over eight months. At baseline, 52 percent of children were overweight or obese. Children attended SCORES > 4 days/week and fitness significantly improved (p < 0.01). BMI z-score decreased by 0.04 (p = 0.10) overall, and by 0.05 (p = 0.08) among obese children, but increased among African-American children. These results suggest that SCORES increases fitness and may improve BMI in some minority children. Effect modification by race may relate to differential growth patterns or engagement in SCORES. These findings suggest community-based programs could effectively address obesity. A randomized trial of the SCORES program is warranted to rigorously examine this type of after-school program's impact on child health.

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.

Use of the motor performance checklist to study motor outcomes in 5-year-olds

AIM

To report findings about the Motor Performance Checklist (MPC) for 5-year-olds, a simple 12-item instrument for assessing gross and fine motor skills, in a research study of neurodevelopmental outcomes after neonatal events.

METHODS

We trained 10 examiners to use the MPC in a study of the outcomes of neonatal jaundice and dehydration in 339 5-year-old children. We compared MPC scores with those on the Wechsler Preschool and Primary Scale of Intelligence-Revised (WPPSI-R), the Beery-Buktenica Developmental Test of Visual-Motor Integration-Fourth Edition (VMI-4), and a standard neurological examination, and compared failure rates on each MPC item across examiners. Parent concerns about their child's development were addressed using the Parent Evaluation of Developmental Status (PEDS).

RESULTS

Children who 'failed' the MPC had 7-10 points lower mean scores on the WPPSI-R subscales (P = 0.001), 9-10 points lower mean scores on the VMI-4 subscales (P = 0.001), and were almost twice as likely to have a 'questionable' neurological examination score (adjusted OR 1.86, 95% CI 1.00-3.53, P = 0.005). On the PEDS, only the concern about the use of arms and hands was significantly associated with MPC failure. We found significant sex differences on four of the 12 MPC items. We also found differences in failure rates by different examiners.

CONCLUSIONS

MPC scores correlated with other measures of neurodevelopment. Because of different failure rates across examiners, examiner terms need to be included if it is used in research studies.

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.

Interaction of hemolysis and hyperbilirubinemia on neurodevelopmental outcomes in the collaborative perinatal project

OBJECTIVE

Our objective was to reanalyze data from the Collaborative Perinatal Project to investigate whether bilirubin is more neurotoxic in newborns with a positive direct antiglobulin test.

PATIENTS AND METHODS

The Collaborative Perinatal Project enrolled 54795 newborns at 12 centers in the United States between 1959 and 1966. We restricted our analysis to those with a birth weight of >/=2000 g and gestational age of >/=36 weeks who had follow-up at 7 to 8 years of age (n = 32808 for IQ testing; n = 33278 for neurologic examination, and n = 16354 for hearing testing). We examined the association between maximum total serum bilirubin levels and these 3 neurodevelopmental outcomes by using multiple linear and logistic regression models. We included interaction terms for the effect of bilirubin category and direct antiglobulin test result on the neurodevelopmental outcome.

RESULTS

Overall, maximum total serum bilirubin level was not a significant predictor of IQ scores. However, there was a statistically significant interaction between a positive direct antiglobulin test and a maximum total serum bilirubin level of >/=25 mg/dL on IQ scores (eg, full-scale IQ: -6.7 points). No similar direct antiglobulin test interaction was seen for those with those with a total serum bilirubin of 20 to 24.9 mg/dL (eg, full-scale IQ: -1.7 points). We found no evidence of an interaction between a positive direct antiglobulin test and total serum bilirubin levels on the risk of an abnormal or suspicious neurologic examination or sensorineural hearing loss.

CONCLUSIONS

In the Collaborative Perinatal Project, evidence of increased bilirubin toxicity in those with a positive direct antiglobulin test result was confined to an adverse association with IQ in those with total serum bilirubin of >/=25 mg/dL.

Office-based treatment and outcomes for febrile infants with clinically diagnosed bronchiolitis

OBJECTIVES

The goals were to describe the (1) frequency of sepsis evaluation and empiric antibiotic treatment, (2) clinical predictors of management, and (3) serious bacterial illness frequency for febrile infants with clinically diagnosed bronchiolitis seen in office settings.

METHODS

The Pediatric Research in Office Settings network conducted a prospective cohort study of 3066 febrile infants (<3 months of age with temperatures >or=38 degrees C) in 219 practices in 44 states. We compared the frequency of sepsis evaluation, parenteral antibiotic treatment, and serious bacterial illness in infants with and without clinically diagnosed bronchiolitis. We identified predictors of sepsis evaluation and parenteral antibiotic treatment in infants with bronchiolitis by using logistic regression models.

RESULTS

Practitioners were less likely to perform a complete sepsis evaluation, urine testing, and cerebrospinal fluid culture and to administer parenteral antibiotic treatment for infants with bronchiolitis, compared with those without bronchiolitis. Significant predictors of sepsis evaluation in infants with bronchiolitis included younger age, higher maximal temperature, and respiratory syncytial virus testing. Predictors of parenteral antibiotic use included initial ill appearance, age of <30 days, higher maximal temperature, and general signs of infant distress. Among infants with bronchiolitis (N = 218), none had serious bacterial illness and those with respiratory distress signs were less likely to receive parenteral antibiotic treatment. Diagnoses among 2848 febrile infants without bronchiolitis included bacterial meningitis (n = 14), bacteremia (n = 49), and urinary tract infection (n = 167).

CONCLUSIONS

In office settings, serious bacterial illness in young febrile infants with clinically diagnosed bronchiolitis is uncommon. Limited testing for bacterial infections seems to be an appropriate management strategy.

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

OBJECTIVE

To estimate the effect of phototherapy and other predictors on the risk of total serum bilirubin (TSB) >or= 25 mg/dL in infants with a TSB of 17 to 22.9 mg/dL at age >or= 48 hours.

STUDY DESIGN

From a cohort of 285295 infants >or= 34 weeks gestation and >or= 2000 g born between 1995 and 2004 in northern California Kaiser hospitals, we identified 17986 with a TSB of 17 to 22.9 mg/dL at age >or= 48 hours. All infants exhibiting a TSB >or= 25 mg/dL were selected as cases for the study. Four randomly selected controls were matched to each case based on the difference between their qualifying TSB and the American Academy of Pediatrics' phototherapy threshold.

RESULTS

A total of 62 cases were identified (0.4%). Six of these (10%) received inpatient phototherapy within 8 hours, along with 101 controls (41%) (adjusted odds ratio [AOR] 0.15; 95% confidence interval [CI] 0.06 to 0.40). Cases more often had lower gestational age (AOR 3.24; 95% CI 1.24 to 8.47 for 38 to 39 weeks and AOR = 3.70; 95% CI 0.61 to 22.4 for 34 to 37 weeks compared with >or= 40-week infants), bruising, (AOR 2.52; 95% CI 1.16 to 5.50), exclusive breast-feeding (AOR 2.09; 95% CI 1.05 to 4.03), and TSB increase of >or= 6 mg/dL/day (AOR 2.39; 95% CI 1.18 to 4.85).

CONCLUSIONS

Phototherapy was 85% effective in preventing TSB >or= 25 mg/dL. The strongest predictors of TSB >or= 25 mg/dL were gestational age, bruising, family history, and rapid rise in TSB.

Predicting significant hyperbilirubinaemia using birth weight

BACKGROUND

A recent study proposed a risk factor scoring system for prediction of hyperbilirubinaemia that assigned increased risk to infants of higher birth weight.

OBJECTIVE

To investigate this novel finding in a large, retrospective cohort analysis.

METHODS

105 384 newborns (> or =2000 g and > or =36 weeks) were analysed, and the effect of higher birth weight on total serum bilirubin (TSB) > or =342 micromol/l was reported using logistic regression to control for gestational age, scalp injury diagnosis, maternal diabetes, method of delivery and other confounders.

RESULTS

The odds ratio for the effect of an additional 500 g of birth weight on TSB > or =342 micromol/l declined with increasing gestational age from 1.55 (95% CI 1.28 to 1.87) at 36 weeks to 1.30 (95% CI 1.12 to 1.50) at 37 weeks and 1.14 (95% CI 1.01 to 1.29) at 38 weeks. There was no association for infants > or =39 weeks.

CONCLUSION

Higher birth weight predicts TSB > or =342 micromol/l in 36-38 week infants, but not in infants > or =39 weeks. Further research should explore the causal mechanism for the association in less-mature infants.

Taking a stand against nuclear proliferation: the pediatrician's role

Nuclear weapons pose a grave threat to the health of children. The Nuclear Nonproliferation Treaty, which for almost 40 years has limited the spread of nuclear weapons, is in danger of unraveling. At the 2000 Nuclear Nonproliferation Treaty Review Conference, 180 countries, including the United States, agreed on 13 practical steps to implement Article VI of the treaty, which calls for nuclear disarmament. However, the United States has acted in contravention of several of those disarmament steps, with announced plans to develop new nuclear weapons and to maintain a large nuclear arsenal for decades to come. Pediatricians, working individually and through organizations such as the American Academy of Pediatrics and International Physicians for the Prevention of Nuclear War, can educate the public and elected officials regarding the devastating and irremediable effects of nuclear weapons on children and the need for policies that comply with and strengthen the Nuclear Nonproliferation Treaty, rather than undermining it. For the children of the world, our goal must be a nuclear weapons convention (similar to the chemical and biological weapons conventions) that would prohibit these weapons globally.

Five-year neurodevelopmental outcome of neonatal dehydration

OBJECTIVE

To determine the long-term outcome of neonatal dehydration.

STUDY DESIGN

We identified 182 newborns who were rehospitalized with dehydration (weight loss > or =12% of birth weight and/or serum sodium > or =150 mEq/L) and 419 randomly selected controls from a cohort of 106,627 term and near-term infants with birth weight > or =2000 g born between 1995 and 1998 in northern California Kaiser Permanente hospitals. Outcomes data were obtained from electronic records, interviews, questionnaire responses, and neurodevelopmental evaluations performed in a masked fashion.

RESULTS

Follow-up data to age at least 2 years were available for 173 of 182 children with a history of dehydration (95%) and 372 of 419 controls (89%) and included formal evaluation at a mean age (+/-standard deviation) of 5.1 +/- 0.12 years for 106 children (58%) and 168 children (40%), respectively. None of the cases developed shock, gangrene, or respiratory failure. Neither crude nor adjusted scores on cognitive tests differed significantly between groups. There was no significant difference between groups in the proportion of children with abnormal neurologic examinations or neurologic diagnoses. Frequencies of parental concerns and reported behavior problems also were not significantly different in the 2 groups.

CONCLUSIONS

Neonatal dehydration in this managed care setting was not associated with adverse neurodevelopmental outcomes in infants born at or near term.