Targeted development and optimization of small-molecule ice recrystallization inhibitors (IRIs) for the cryopreservation of biological systems

Despite the routine use of cryopreservation for the storage of biological materials, its outcomes are often sub-optimal (including reduced post-thaw viability, recovery, and functionality) due to the damage caused by uncontrolled ice growth. Traditional cryoprotective agents (CPAs), including dimethyl sulfoxide (DMSO), fail to prevent damage caused by ice growth and concerns over CPA cytotoxicity have fostered an increased interest in developing improved CPAs and cryoprotection strategies. The inhibition of ice recrystallization by natural antifreeze (glyco)proteins [AF(G)Ps] to improve cryopreservation outcomes has been examined; however, the ice binding properties of these substances and their challenging large-scale production make them poor CPA candidates. Therefore, the development and deployment of biocompatible, small-molecule ice recrystallization inhibitors (IRIs) for use as CPAs is a worthwhile objective. Extensive structure-activity relationship studies on AF(G)Ps revealed that simple carbohydrate derivatives could inhibit ice recrystallization. It was later discovered that this activity could be fine-tuned by delicately balancing the molecule's hydrophobicity and hydrophilicity. Current generation small-molecule IRIs have been meticulously designed to avoid binding to the surface of ice and subsequent biological testing (for both cytotoxicity and cryopreservation efficacy) has demonstrated significant improvements to the cryopreservation outcomes of several cell types. However, an individualized cell-specific approach for the simultaneous assessment of multiple cryopreservation outcomes is necessary to realize the full potential of IRIs as CPAs. This article provides a detailed overview of the development of small-molecule carbohydrate-based IRIs and highlights the crucial cell-specific biological considerations that must be taken into account when assessing cryopreservation outcomes. https://doi.org/10.54680/fr24210110112.

Independent Impact of Eat, Sleep, Console Assessment on Neonatal Opioid Withdrawal Syndrome

Compared with the Finnegan Neonatal Abstinence Scoring System (FNASS), the Eat, Sleep, Console (ESC) approach reduces pharmacotherapy and length of stay (LOS) for neonatal opioid withdrawal syndrome (NOWS) infants. The independent outcome contribution of ESC is unknown as the approach combines ESC assessment with additional management changes. Our objective was to evaluate ESC assessment's independent impact on outcomes compared with FNASS. We conducted a retrospective cohort study of in utero opioid-exposed infants ≥35 weeks gestation managed with FNASS versus ESC. Outcomes included pharmacotherapy initiation, LOS, length of pharmacotherapy, and emergency department visit/readmissions. Among 151 FNASS and 100 ESC managed infants, pharmacotherapy initiation (P = .47), LOS for all infants (P = .49), and LOS for pharmacologically treated infants (P = .68) were similar. Length of pharmacotherapy did not differ (P = .84). Emergency department evaluation/NOWS readmission was equally rare (P = .65). Using equivalent models of care, comparison of ESC and FNASS assessment tools showed no difference in NOWS outcomes.

NICU Versus Mother/Baby Unit Admission for Low-Acuity Infants Born at 35 Weeks' Gestation

OBJECTIVES

To estimate the effect of NICU admission of low-acuity infants born at 35 weeks' gestation versus care in a mother/baby unit, on inpatient and outpatient medical outcomes.

METHODS

This retrospective cohort study included 5929 low-acuity infants born at 350/7 to 356/7 weeks' gestation at 13 Kaiser Permanente Northern California hospitals with level II or level III NICUs between January 1, 2011, and December 31, 2021. Exclusion criteria included congenital anomalies and early respiratory support or antibiotics. We used multivariable regression and regression discontinuity analyses to control for confounding variables.

RESULTS

Infants admitted to the NICU within 2 hours of birth (n = 862, 14.5%) had a 58 hour adjusted (98-hour unadjusted) longer length of stay. NICU admission was associated with an increased probability of a length of stay ≥96 hours (67% vs 21%; adjusted odds ratio [aOR], 4.94; 95% confidence interval [CI], 3.96-6.16). Regression discontinuity results suggested a similar (57 hour) increase in length of stay. Readmission risk, primarily for jaundice, was lower for those admitted to the NICU (3% vs 6%; aOR, 0.43; 95% CI, 0.27-0.69). Infants admitted to the NICU were slightly less likely to be receiving exclusive breast milk at 6-month follow-up (15% vs 25%; aOR, 0.73; 95% CI, 0.55-0.97; adjusted marginal risk difference -5%).

CONCLUSIONS

Admitting low-acuity infants born at 35 weeks' gestation to the NICU was associated with decreased readmission, but with longer length of stay and decreased exclusive breast milk feeding at 6 months. Routine NICU admission may be unnecessary for low-acuity infants born at 35 weeks' gestation.

Time to positivity of blood cultures in neonatal late-onset bacteraemia

OBJECTIVE

To determine the time to positivity (TTP) of blood cultures among infants with late-onset bacteraemia and predictors of TTP >36 hours.

DESIGN

Retrospective cohort study.

SETTING

16 birth centres in two healthcare systems.

PATIENTS

Infants with positive blood cultures obtained >72 hours after birth.

OUTCOME

The main outcome was TTP, defined as the time interval from specimen collection to when a neonatal provider was notified of culture growth. TTP analysis was restricted to the first positive culture per infant. Patient-specific and infection-specific factors were analysed for association with TTP >36 hours.

RESULTS

Of 10 235 blood cultures obtained from 3808 infants, 1082 (10.6%) were positive. Restricting to bacterial pathogens and the first positive culture, the median TTP (25th-75th percentile) for 428 cultures was 23.5 hours (18.4-29.9); 364 (85.0%) resulted in 36 hours. Excluding coagulase-negative staphylococci (CoNS), 275 of 294 (93.5%) cultures were flagged positive by 36 hours. In a multivariable model, CoNS isolation and antibiotic pretreatment were significantly associated with increased odds of TTP >36 hours. Projecting a 36-hour empiric duration at one site and assuming that all negative evaluations were associated with an empiric course of antibiotics, we estimated that 1164 doses of antibiotics would be avoided in 629 infants over 10 years, while delaying a subsequent antibiotic dose in 13 infants with bacteraemia.

CONCLUSIONS

Empiric antibiotic administration in late-onset infection evaluations (not targeting CoNS) can be stopped at 36 hours. Longer durations (48 hours) should be considered when there is pretreatment or antibiotic therapy is directed at CoNS.

Use of Complete Blood Cell Count Components to Screen for Hereditary Spherocytosis in Neonates

BACKGROUND AND OBJECTIVES

The neonatal hereditary spherocytosis (HS) index, defined as the mean corpuscular hemoglobin concentration divided by the mean corpuscular volume, has been proposed as a screening tool for HS in neonates. In a population of mostly white infants, an HS Index >0.36 was 97% sensitive and >99% specific. We evaluated the utility of the HS Index among a more racially and ethnically diverse population and determined if its discrimination varies with total serum bilirubin (TSB) levels.

METHODS

Infants born at ≥35 weeks' gestation at 15 Kaiser Permanente Northern California hospitals from 1995 to 2015 were eligible (N = 670 272). Erythrocyte indices from the first complete blood count drawn at ≤7 days and TSB levels drawn at ≤30 days were obtained. Diagnoses of HS were confirmed via chart review.

RESULTS

HS was confirmed in 79 infants, 1.2 per 10 000. HS was more common among infants of white and "other" race or ethnicity and among those with higher peak TSB levels. The area under the receiver operating characteristic curve for the HS Index was 0.84 (95% confidence interval 0.78-0.90). Likelihood ratios ranged from 10.1 for an HS Index ≥0.380 to 0.1 for an HS Index <0.310. Dichotomized at 0.36, the HS Index was 56% sensitive and 93% specific. Discrimination of the HS Index appeared best among infants with TSB levels <10 mg/dL.

CONCLUSIONS

The HS Index, when obtained from a CBC drawn within the first week after birth, had only modest ability to alter the probability of HS.

Predicting the Need for Phototherapy After Discharge

BACKGROUND AND OBJECTIVES

Bilirubin screening before discharge is performed to identify neonates at risk for future hyperbilirubinemia. The American Academy of Pediatrics recommends using a graph of bilirubin levels by age (the Bhutani Nomogram) to guide follow-up and a different graph to determine phototherapy recommendations. Our objective was to evaluate predictive models that incorporate the difference between the last total serum bilirubin (TSB) before discharge and the American Academy of Pediatrics phototherapy threshold (Δ-TSB) to predict a postdischarge TSB above the phototherapy threshold by using a single graph.

METHODS

We studied 148 162 infants born at ≥35 weeks' gestation at 11 Kaiser Permanente Northern California facilities from 2012 to 2017 whose TSB did not exceed phototherapy levels and who did not receive phototherapy during the birth hospitalization. We compared 3 logistic models (Δ-TSB; Δ-TSB-Plus, which included additional variables; and the Bhutani Nomogram) by using the area under the receiver operating characteristic curve (AUC) in a 20% validation subset.

RESULTS

A total of 2623 infants (1.8%) exceeded the phototherapy threshold postdischarge. The predicted probability of exceeding the phototherapy threshold after discharge ranged from 56% for a predischarge Δ-TSB 0 to 1 mg/dL below the threshold to 0.008% for Δ-TSB >7 mg/dL below the threshold. Discrimination was better for the Δ-TSB model (AUC 0.93) and the Δ-TSB-Plus model (AUC 0.95) than for the Bhutani Nomogram (AUC 0.88).

CONCLUSIONS

The use of Δ-TSB models had excellent ability to predict postdischarge TSB above phototherapy thresholds and may be simpler to use than the Bhutani Nomogram.

A simplified CD34+ based preharvest prediction tool for HPC(A) collection

BACKGROUND

Hematopoietic stem cell transplantation is an important treatment that is dependent on the collection of sufficient CD34+ hematopoietic progenitor cells. The peripheral blood CD34 count (PB CD34+ counts) measured by flow cytometry can be used in predicting CD34+ stem cell yields hours before the completion of collection. Previously described formulas to predict the yield have used many different variables. As such, there is currently no consensus on an industry-standard algorithm or formula.

STUDY DESIGN AND METHODS

Retrospective reviews of same-day PB CD34+ counts and the ensuing absolute CD34+ yields of mobilized donors (allogeneic and autologous) were used to develop and validate a formula using regression analysis to predict the CD34+ stem cell yield. A metric of prediction correlation, using root mean square error (RMSE), was used to assess the robustness of our prediction formula in addition to comparisons with two other published formulas, as well as subset analysis.

RESULTS

A formula in the form of y = mx^b with r = 0.95 and 95% confidence intervals was generated and validated. The ratio of actual to predicted yield demonstrated a high correlation coefficient (r = 0.96) with linear regression and overall RMSE of 228.4, which was lower than the two prior studies (calculated RMSE = 330.8 and 405.2). Subset analyses indicated male patients, lymphoma patients, and patients >60 years of age demonstrated lower RMSEs.

CONCLUSION

We have demonstrated a simple yet robust formula that can be used prospectively to accurately predict the CD34+ stem cell yield in both autologous and allogeneic donors, which also accounts for recipient weight.

Automated early detection of obstetric complications: theoretic and methodologic considerations

Compared with adults who are admitted to general medical-surgical wards, women who are admitted to labor and delivery services are at much lower risk of experiencing unexpected critical illness. Nonetheless, critical illness and other complications that put either the mother or fetus at risk do occur. One potential approach to prevention is to use automated early warning systems, such as those used for nonpregnant adults. Predictive models that use data extracted in real time from electronic records constitute the cornerstone of such systems. This article addresses several issues that are involved in the development of such predictive models: specification of temporal characteristics, choice of denominator, selection of outcomes for model calibration, potential uses of existing adult severity of illness scores, approaches to data processing, statistical considerations, validation, and options for instantiation. These have not been addressed explicitly in the obstetrics literature, which has focused on the use of manually assigned scores. In addition, this article provides some results from work in progress to develop 2 obstetric predictive models with the use of data from 262,071 women who were admitted to a labor and delivery service at 15 Kaiser Permanente Northern California hospitals between 2010 and 2017.

Incremental Cost of Prematurity by Week of Gestational Age

Objective  This study was aimed to compare health care costs and utilization at birth through 1 year, between preterm and term infants, by week of gestation. Methods  A cross-sectional study of infants born at ≥ 23 weeks of gestational age (GA) at Kaiser Permanente Northern California facilities between 2000 and 2011, using outcomes data from an internal neonatal registry and cost estimates from an internal cost management database. Adjusted models yielded estimates for cost differences for each GA group. Results  Infants born at 25 to 37 weeks incur significantly higher birth hospitalization costs and experience significantly more health care utilization during the initial year of life, increasing progressively for each decreasing week of gestation, when compared with term infants. Among all very preterm infants (≤ 32 weeks), each 1-week decrease in GA is associated with incrementally higher rates of mortality and major morbidities. Conclusion  We provide estimates of potential cost savings that could be attributable to interventions that delay or prevent preterm delivery. Cost differences were most extreme at the lower range of gestation (≤ 30 weeks); however, infants born moderately preterm (31-36 weeks) also contribute substantially to the burden, as they represent a higher proportion of total births.

Prevalence of infant bronchiolitis-coded healthcare encounters attributable to RSV

AIM

We sought to determine the proportion of bronchiolitis episodes attributable to respiratory syncytial virus (RSV) among ICD-9 coded infant bronchiolitis episodes which were tested for RSV.

METHODS

Bronchiolitis healthcare encounters were extracted from Kaiser Permanente Northern California databases for years 2006 to 2009. We used ICD-9 codes for bronchiolitis to capture bronchiolitis-related healthcare encounters including hospital admissions (Hospitalization), emergency department visits (EDV), and outpatient visits (OPV). We reported the monthly proportion of RSV-positive bronchiolitis episodes among tested bronchiolitis episodes. We used logistic regression to assess association between bronchiolitis episodes and patient demographic and health care characteristics. We also used logistic regression to assess association between decision to test and patient demographics and health care characteristics.

RESULTS

Among 10,411 ICD-9 coded infant bronchiolitis episodes, 29% were RSV tested. Fifty one percent of those tested were RSV positive. Between December and February, and in infants ≤6 months, the proportion of bronchiolitis episodes that were attributable to RSV was 77.2% among hospitalized episodes, 78.3% among EDV episodes, and 60.9% among OPV episodes, respectively. The proportion of RSV-positive bronchiolitis episodes varied based upon infant age at diagnosis, level of health care service used, and time of the year of the episode.

CONCLUSION

Estimation of the proportion of ICD-9 coded bronchiolitis episodes attributable to RSV is more specific when restricting to bronchiolitis episodes during peak months, younger infant age, and those requiring higher level of healthcare.

Hyperbilirubinemia, Phototherapy, and Childhood Asthma

OBJECTIVES

Our aim was to quantify the associations of both hyperbilirubinemia and phototherapy with childhood asthma using a population-based cohort with total serum bilirubin (TSB) levels.

METHODS

Retrospective cohort study of infants born at ≥35 weeks' gestation in the Kaiser Permanente Northern California health system (n = 109 212) from 2010 to 2014. Cox models were used to estimate hazard ratios (HRs) for a diagnosis of asthma.

RESULTS

In the study, 16.7% of infants had a maximum TSB level of ≥15 mg/dL, 4.5% of infants had a maximum TSB level of ≥18 mg/dL, and 11.5% of infants received phototherapy. Compared with children with a maximum TSB level of 3 to 5.9 mg/L, children with a TSB level of 9 to 11.9 mg/dL, 12 to 14.9 mg/dL, and 15 to 17.9 mg/dL were at an increased risk for asthma (HR: 1.22 [95% confidence interval (CI): 1.11-1.3], HR: 1.18 [95% CI: 1.08-1.29], and HR: 1.30 [95% CI: 1.18-1.43], respectively). Children with a TSB level of ≥18 mg/dL were not at an increased risk for asthma (HR: 1.04; 95% CI: 0.90-1.20). In propensity-adjusted analyses, phototherapy was not associated with asthma (HR: 1.07; 95% CI: 0.96-1.20).

CONCLUSIONS

Modest levels of hyperbilirubinemia were associated with an increased risk of asthma, but an association was not seen at higher levels. No dose-response relationship was seen. Using phototherapy to prevent infants from reaching these modest TSB levels is unlikely to be protective against asthma.

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.

Effectiveness of Respiratory Syncytial Virus Immunoprophylaxis in Reducing Bronchiolitis Hospitalizations Among High-Risk Infants

We sought to determine the real-world effectiveness of respiratory syncytial virus (RSV) immunoprophylaxis in a population-based cohort to inform policy. The study population included infants born during 1996-2008 and enrolled in the Kaiser Permanente Northern California integrated health-care delivery system. During the RSV season (November-March), the date of RSV immunoprophylaxis administration and the following 30 days were defined as RSV immunoprophylaxis protected period(s), and all other days were defined as unprotected period(s). Numbers of bronchiolitis hospitalizations were determined using International Classification of Diseases, Ninth Revision, codes during RSV season. We used a proportional hazards model to estimate risk of bronchiolitis hospitalization when comparing infants' protected period(s) with unprotected period(s). Infants who had ever received RSV immunoprophylaxis had a 32% decreased risk of bronchiolitis hospitalization (adjusted hazard ratio = 0.68, 95% confidence interval: 0.46, 1.00) when protected periods were compared with unprotected periods. Infants with chronic lung disease (CLD) had a 52% decreased risk of bronchiolitis hospitalization (adjusted hazard ratio = 0.48, 95% confidence interval: 0.25, 0.94) when protected periods were compared with unprotected periods. Under the new 2014 American Academy of Pediatrics (AAP) guidelines, 48% of infants eligible for RSV immunoprophylaxis on the basis of AAP guidelines in place at birth would no longer be eligible, but nearly all infants with CLD would remain eligible. RSV immunoprophylaxis is effective in decreasing hospitalization. This association is greatest for infants with CLD, a group still recommended for receipt of RSV immunoprophylaxis under the new AAP guidelines.

Accuracy of international classification of diseases, ninth revision, codes for postpartum hemorrhage among women undergoing cesarean delivery

BACKGROUND

Determining the accuracy of International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9) codes for postpartum hemorrhage (PPH) is vital for reaching valid conclusions about the epidemiology of PPH. Our primary objectives were to assess the performance characteristics of ICD-9 PPH codes against a reference standard using estimated blood loss (EBL) among a cohort undergoing Cesarean delivery.

STUDY DESIGN AND METHODS

We analyzed maternal discharge and EBL data from women who underwent Cesarean delivery at Kaiser Permanente Northern California facilities between 2010 and 2013. We defined PPH as an EBL of at least 1000 mL. In a secondary analysis, ICD-9 performance characteristics were assessed using an EBL of at least 1500 mL to classify severe PPH.

RESULTS

We identified 35,614 hospitalizations for Cesarean delivery. Using EBL of at least 1000 mL as the "gold standard," PPH codes had a sensitivity of 27.8%, specificity of 97%, positive predictive value (PPV) of 74.5%, and a negative predictive value (NPV) of 80.9%. The prevalence of a PPH code (9%) was lower than the prevalence using a blood loss of at least 1000 mL (24%). Using a reference standard of EBL of at least 1500 mL, PPH codes had a sensitivity of 61.7%, specificity of 93.8%, PPV of 34.2%, and NPV of 97.9%.

CONCLUSION

PPH ICD-9 codes have high specificity, moderately high PPVs and NPVs, and low sensitivity. An EBL of at least 1500 mL as a reference standard has higher sensitivity. Our findings suggest that, for women undergoing Cesarean delivery, quality improvement efforts are needed to enhance PPH ICD-9 coding accuracy in administrative data sets.

Is chemotherapy always required for cancer in pregnancy? An observational study

BACKGROUND

Cancer in pregnancy is relatively rare, but the incidence is increasing. Several studies show that cytotoxic agents are safe to use in pregnancy from the second trimester onwards.

AIMS

This study assesses the maternal and foetal outcomes of cancers diagnosed during pregnancy. In particular, it focuses on a subset of women who elected to defer systemic chemotherapy until after delivery. This study examines if all cancers need to be treated during pregnancy or if, in certain cases, treatment can be safely deferred until after full-term delivery.

METHODS

This is a retrospective observational study of women diagnosed with cancer during pregnancy in an Irish cancer centre over a 27-year period. All women diagnosed with cancer during pregnancy who were referred to the medical oncology department for consideration of chemotherapy were included in this study. Medical and pharmacy records were extensively reviewed.

RESULTS

Twenty-five women were diagnosed with cancer in pregnancy and referred to medical oncology for consideration of systemic chemotherapy. Sixteen women (64%) commenced chemotherapy during pregnancy, seven women (28%) did not receive chemotherapy while pregnant, but commenced treatment immediately after delivery, and two (8%) did not receive any systemic chemotherapy at all. Of the seven women who commenced chemotherapy after delivery, six (85.7%) were diagnosed before 30/40 gestation. There were three cases of Hodgkin's lymphoma, two breast cancers and one ovarian cancer. After a median follow-up of 12 years, all six mothers remain disease-free.

CONCLUSIONS

This study identified a select cohort of patients that did not receive chemotherapy during pregnancy. There were no adverse outcomes to mothers due to delayed treatment.

A Quantitative, Risk-Based Approach to the Management of Neonatal Early-Onset Sepsis

IMPORTANCE

Current algorithms for management of neonatal early-onset sepsis (EOS) result in medical intervention for large numbers of uninfected infants. We developed multivariable prediction models for estimating the risk of EOS among late preterm and term infants based on objective data available at birth and the newborn's clinical status.

OBJECTIVES

To examine the effect of neonatal EOS risk prediction models on sepsis evaluations and antibiotic use and assess their safety in a large integrated health care system.

DESIGN, SETTING, AND PARTICIPANTS

The study cohort includes 204 485 infants born at 35 weeks' gestation or later at a Kaiser Permanente Northern California hospital from January 1, 2010, through December 31, 2015. The study compared 3 periods when EOS management was based on (1) national recommended guidelines (baseline period [January 1, 2010, through November 31, 2012]), (2) multivariable estimates of sepsis risk at birth (learning period [December 1, 2012, through June 30, 2014]), and (3) the multivariable risk estimate combined with the infant's clinical condition in the first 24 hours after birth (EOS calculator period [July 1, 2014, through December 31, 2015]).

MAIN OUTCOMES AND MEASURES

The primary outcome was antibiotic administration in the first 24 hours. Secondary outcomes included blood culture use, antibiotic administration between 24 and 72 hours, clinical outcomes, and readmissions for EOS.

RESULTS

The study cohort included 204 485 infants born at 35 weeks' gestation or later: 95 343 in the baseline period (mean [SD] age, 39.4 [1.3] weeks; 46 651 male [51.0%]; 37 007 white, non-Hispanic [38.8%]), 52 881 in the learning period (mean [SD] age, 39.3 [1.3] weeks; 27 067 male [51.2%]; 20 175 white, non-Hispanic [38.2%]), and 56 261 in the EOS calculator period (mean [SD] age, 39.4 [1.3] weeks; 28 575 male [50.8%]; 20 484 white, non-Hispanic [36.4%]). In a comparison of the baseline period with the EOS calculator period, blood culture use decreased from 14.5% to 4.9% (adjusted difference, -7.7%; 95% CI, -13.1% to -2.4%). Empirical antibiotic administration in the first 24 hours decreased from 5.0% to 2.6% (adjusted difference, -1.8; 95% CI, -2.4% to -1.3%). No increase in antibiotic use occurred between 24 and 72 hours after birth; use decreased from 0.5% to 0.4% (adjusted difference, 0.0%; 95% CI, -0.1% to 0.2%). The incidence of culture-confirmed EOS was similar during the 3 periods (0.03% in the baseline period, 0.03% in the learning period, and 0.02% in the EOS calculator period). Readmissions for EOS (within 7 days of birth) were rare in all periods (5.2 per 100 000 births in the baseline period, 1.9 per 100 000 births in the learning period, and 5.3 per 100 000 births in the EOS calculator period) and did not differ statistically (P = .70). Incidence of adverse clinical outcomes, including need for inotropes, mechanical ventilation, meningitis, and death, was unchanged after introduction of the EOS calculator.

CONCLUSIONS AND RELEVANCE

Clinical care algorithms based on individual infant estimates of EOS risk derived from a multivariable risk prediction model reduced the proportion of newborns undergoing laboratory testing and receiving empirical antibiotic treatment without apparent adverse effects.

Outcomes of Admissions for Preterm Labor

Objective  This study aims to quantitate the incidence of preterm labor (PTL) admissions and determine the frequency and predictors of preterm delivery (PTD) during these admissions. Study Design  Retrospective cohort of singleton pregnancies within Kaiser Permanente Northern California, 2001 to 2011. PTL admissions were defined as inpatient encounters > 24 hours with an International Classification of Diseases, 9th Revision code for PTL. Results  Total study population was 365,897 with PTL admission rate 11%. PTD occurred in 85% of pregnancies with PTL admission. Delivery occurred within 48 hours of admission in 96% ≥34 weeks, 67% 31 to 33 weeks, and 51.9% <31 weeks. Predictors of delivery during PTL admission included gestational age 34 to 36 weeks (adjusted odds ratio [aOR], 6.90), chorioamnionitis (aOR, 105.58), and preterm rupture of membranes (aOR 19.29). Conclusion  We demonstrate a high rate of PTD per PTL admission in a highly integrated health care system. More work is needed to determine optimal practices for hospitalization and treatment of women diagnosed with PTL.

Respiratory syncytial virus immunoprophylaxis in high-risk infants and development of childhood asthma

BACKGROUND

Respiratory syncytial virus (RSV) lower respiratory tract infection is implicated in asthma development. RSV immunoprophylaxis during infancy is efficacious in preventing RSV-related hospitalizations and has been associated with decreased wheezing in the first years of life.

OBJECTIVE

We investigated whether greater adherence to immunoprophylaxis in infants at high risk for severe RSV would be associated with decreased childhood asthma.

METHODS

We conducted a retrospective cohort investigation including children born from 1996-2003 who were enrolled in Kaiser Permanente Northern California or Tennessee Medicaid and eligible to receive RSV immunoprophylaxis. Asthma was defined at 4.5 to 6 years of age by using asthma-specific health care visits and medication fills. We classified children into immunoprophylaxis eligibility groups and calculated adherence (percentage receipt of recommended doses). We used a set of statistical strategies (multivariable logistic regression and propensity score [PS]-adjusted and PS-matched analyses) to overcome confounding by medical complexity because infants with higher adherence (≥70%) have higher prevalence of chronic lung disease, lower birth weight, and longer nursery stays.

RESULTS

By using multivariable logistic regression and PS-adjusted models in the combined group, higher adherence to RSV immunoprophylaxis was not associated with decreased asthma. However, in PS-matched analysis, treated children with 70% or greater adherence had decreased odds of asthma compared with those with 20% or less adherence (odds ratio, 0.62; 95% CI, 0.50-0.78).

CONCLUSIONS

This investigation of RSV immunoprophylaxis in high-risk children primarily found nonsignificant associations on prevention of asthma in specific preterm groups. Our findings highlight the need for larger studies and prospective cohorts and provide estimates of potential preventive effect sizes in high-risk children.

Weight Change Nomograms for the First Month After Birth

OBJECTIVE

Clinicians expect newborns to surpass birth weight by age 10 to 14 days, yet few studies have examined the natural history of weight change in the weeks after birth. We sought to determine the distribution of weight loss and subsequent regain during the first month, the proportion not surpassing birth weight by 14 and 21 days, and whether findings differed by delivery mode.

METHODS

For 161 471 singleton neonates delivered at ≥36 weeks' gestation at Kaiser Permanente Northern California Medical Centers between 2009 and 2013 and weighing 2000 to 5000 g at birth, we extracted daily weights from inpatient electronic records and weights from outpatient visits in the first month. Quantile regression appropriate for repeated measures was used to estimate percentiles of weight change as a function of time after birth, stratified by delivery mode.

RESULTS

After exclusions, weight data were analyzed from 143 889 newborns (76% born vaginally). Based on percentile estimates, 50% of newborns were at or above birth weight at 9 and 10 days after vaginal and cesarean delivery, respectively. Among those delivered vaginally, 14% and 5% were not back to birth weight by 14 and 21 days, respectively. For those delivered by cesarean, 24% and 8% were not back to birth weight by 14 and 21 days, respectively.

CONCLUSIONS

It is not uncommon for newborns to be below birth weight 10 to 14 days after delivery. A larger percentage of newborns delivered by cesarean had yet to regain birth weight at every time point through 1 month.

Phototherapy and Risk of Type 1 Diabetes

BACKGROUND AND OBJECTIVE

Increases in both phototherapy use and the incidence of type 1 diabetes mellitus (DM-1) have been reported. One large study has suggested a strong association between them. Our objective was to quantify any association between neonatal phototherapy and DM-1 in a northern California integrated health care system.

METHODS

This retrospective cohort study included 499 642 children born at ≥35 weeks' gestation in 15 Kaiser Permanente Northern California hospitals from 1995 to 2011 and followed until March 31, 2014. We ascertained phototherapy, bilirubin levels, and other covariates from electronic records. We identified DM-1 cases using a diabetes registry and inpatient and outpatient diagnoses. We used traditional and propensity-adjusted Cox models to quantify associations.

RESULTS

Phototherapy use increased from 2.7% in 1995 to 16.0% in 2011. DM-1 was diagnosed in 37 of 39 406 children who had received phototherapy (15.1 per 100 000 person-years; mean follow-up 6.2 years) and 712 of 460 236 who had not (18.8 per 100 000 person-years; mean follow-up 8.2 years). There was no evidence of increasing diabetes incidence. We found no association between phototherapy and DM-1 in either unadjusted analyses (incidence rate ratio 0.81; 95% confidence interval, 0.56 to 1.12) or analyses adjusted for hyperbilirubinemia and other covariates (hazard ratio 1.06; 95% confidence interval, 0.78 to 1.45). DM-1 incidence was most strongly associated with race and ethnicity, with whites at highest risk (25.6 per 100 000) and Asians at lowest risk (8.9 per 100 000).

CONCLUSIONS

We found no evidence of increased DM-1 risk in children who had received phototherapy.

Risk of Autism Associated With Hyperbilirubinemia and Phototherapy

OBJECTIVE

Whether neonatal hyperbilirubinemia and/or phototherapy increase the risk of autism spectrum disorder (ASD) is unclear. We sought to quantify the risk of ASD associated with elevated total serum bilirubin (TSB) levels and with phototherapy.

METHODS

In a retrospective cohort study of 525 409 infants born at ≥35 weeks' gestation in 15 Kaiser Permanente Northern California (KPNC) hospitals, 1995-2011, we obtained all TSB levels and determined which infants received phototherapy. From the KPNC Autism Registry, we identified patients with ASD diagnosed at a KPNC Autism Center, by a clinical specialist, or by a pediatrician. We calculated Cox proportional hazard ratios (HRs) for time to diagnosis of ASD, adjusting for confounding factors.

RESULTS

Among infants in the birth cohort, 2% had at least 1 TSB level ≥20 mg/dL, and 8% received phototherapy. The rate of ASD was 13 per 1000 births. Crude analyses revealed an association between TSB ≥20 and ASD (relative risk: 1.4; 95% confidence interval [CI]: 1.1-1.6), and between phototherapy and ASD (relative risk: 1.7; 95% CI: 1.5-1.8). After adjusting for confounders, TSB ≥20 (HR: 1.09; 95% CI: 0.89-1.35) and phototherapy (HR: 1.10; 95% CI: 0.98-1.24) were no longer significantly associated with ASD. Independent risk factors for ASD included maternal and paternal age; maternal and paternal higher education; male sex; birth weight <2500 g or ≥4200 g; and later year of birth.

CONCLUSIONS

After adjustment for the effects of sociodemographic factors and birth weight, neither hyperbilirubinemia nor phototherapy was an independent risk factor for ASD.

Patterns and predictors of severe postpartum anemia after Cesarean section

BACKGROUND

Postpartum anemia is associated with maternal and perinatal morbidity. Population-level data may inform guideline development for postpartum anemia screening. Our objectives were to evaluate the associations between potential predictors (predelivery anemia and postpartum hemorrhage [PPH]) with severe postpartum anemia after Cesarean section.

STUDY DESIGN AND METHODS

Data were collected from 70,939 hospitalizations for Cesarean section performed at Kaiser Permanente Northern California facilities between 2005 and 2013. Severe postpartum anemia was defined as a hemoglobin (Hb) level of less than 8 g/dL before hospital discharge. Using multivariable logistic regression, we assessed the associations between predelivery anemia and PPH with severe postpartum anemia. Distributions of these characteristics among women with severe postpartum anemia were evaluated.

RESULTS

The overall rate of severe postpartum anemia was 7.3% (95% confidence interval [CI], 7.1%-7.4%). Severe postpartum anemia was strongly associated with a predelivery Hb level between 10 and 10.9 g/dL (adjusted odds ratio [aOR], 5.4; 95% CI, 4.89-5.91), predelivery Hb level of less than 10 g/dL (aOR, 30.6; 95% CI, 27.21-34.6), and PPH (aOR, 8.45; 95% CI, 7.8-9.16). The proportions of women with severe postpartum anemia were highest for those experiencing PPH but no predelivery anemia (12.2%; 95% CI, 11.0%-13.6%) and those who did not incur PPH nor predelivery anemia (10.7%; 95% CI, 9.6%-12.0%).

CONCLUSIONS

Our findings suggest that PPH and predelivery anemia are strong independent risk factors for severe postpartum anemia. Optimization of patients' Hb before delivery may reduce the incidence of severe anemia after Cesarean section.

Association Between Laboratory Calibration of a Serum Bilirubin Assay, Neonatal Bilirubin Levels, and Phototherapy Use

IMPORTANCE

The American Academy of Pediatrics treatment recommendations for neonatal jaundice are based on age-specific total serum bilirubin (TSB) levels. In May 2012, Ortho Clinical Diagnostics adjusted the calibrator values for Vitros Chemistry Products BuBc Slides (Ortho Clinical Diagnostics), a widely used method to quantify TSB, after concerns of positively biased results.

OBJECTIVE

To investigate the association between recalibration of a reflectance spectrophotometry serum bilirubin assay and TSB levels and phototherapy use among newborns.

DESIGN, SETTING, AND PARTICIPANTS

Descriptive study comparing TSB levels and phototherapy use before and after recalibration at Kaiser Permanente Northern California, a large, integrated health care delivery system. The study evaluated live births at or after 35 weeks' gestation at 12 facilities that used universal serum bilirubin screening before (January 1, 2010, through April 30, 2012; n = 61 677) and after (July 1, 2012, through December 31, 2013; n = 42 571) recalibration. The analysis took place in December 2015.

INTERVENTION

Recalibration of bilirubin testing instruments.

MAIN OUTCOMES AND MEASURES

Proportions of newborns with (1) at least 1 TSB value at or above 15 mg/dL; (2) at least 1 TSB level exceeding the American Academy of Pediatrics phototherapy threshold; (3) phototherapy during the birth hospitalization; and (4) at least 1 readmission for phototherapy.

RESULTS

In 104 420 infants (61 677 in the prerecalibration period and 42 511 in the postrecalibration period), a TSB was obtained in 99.2% of infants during birth and in 99.5% of infants within the first 30 days after birth. The postrecalibration period was associated with a 1.25 mg/dL (95% CI, 1.19-1.31; P < .001) decrease in mean maximum TSB, which led to a 39% relative reduction (from 20.4% to 12.4%) in infants with a TSB level of 15 mg/dL or more and a 51% relative reduction (from 9.3% to 4.5%) in infants with a TSB level that was at or above the American Academy of Pediatrics phototherapy threshold. Phototherapy during birth hospitalizations was reduced by 59% (absolute risk reduction, 5.5%; 95% CI, 4.7%-6.1%) and readmissions for phototherapy by 53% (absolute risk reduction, 1.8%; 95% CI, 1.4%-2.3%).

CONCLUSIONS AND RELEVANCE

Modest recalibration-induced reductions in mean TSB concentrations was associated with a significant reduction in the percentage of infants with clinically significant hyperbilirubinemia. Current laboratory accuracy standards are insufficient to detect biases that can have significant clinical effect. These data underline the need for increased integration of laboratory expertise into clinical guidelines and to support international initiatives to standardize laboratory measurements.

Retrospective Cohort Study of Phototherapy and Childhood Cancer in Northern California

OBJECTIVE

To investigate the association between neonatal phototherapy use and childhood cancer.

METHODS

This retrospective cohort study included 499 621 children born at ≥35 weeks' gestation from 1995 to 2011 in Kaiser Permanente Northern California hospitals, who survived to hospital discharge and were followed ≥60 days. We obtained data on home and inpatient phototherapy, covariates, and cancer incidence from electronic records. We used propensity-adjusted Cox and Poisson models to control for confounding and unequal follow-up times.

RESULTS

There were 60 children with a diagnosis of cancer among 39 403 exposed to phototherapy (25 per 100 000 person-years), compared with 651 of 460 218 unexposed children (18 per 100 000 person-years; incidence rate ratio [IRR] 1.4; P = .01). Phototherapy was associated with increased rates of any leukemia (IRR 2.1; P = .0007), nonlymphocytic leukemia (IRR 4.0; P = .0004), and liver cancer (IRR 5.2; P = .04). With adjustment for a propensity score that incorporated bilirubin levels, chromosomal disorders, congenital anomalies, and other covariates, associations were no longer statistically significant: Adjusted hazard ratios (95% confidence intervals) were 1.0 (0.7-1.6) for any cancer, 1.6 (0.8-3.5) for any leukemia, 1.9 (0.6-6.9) for nonlymphocytic leukemia, and 1.4 (0.2-12) for liver cancer. Upper limits of 95% confidence intervals for adjusted 10-year excess risk were generally <0.1% but reached 4.4% for children with Down syndrome.

CONCLUSIONS

Although phototherapy use was associated with increased cancer rates (particularly nonlymphocytic leukemia), control for confounding variables eliminated or attenuated the associations. Nonetheless, the possibility of even partial causality suggests that avoiding unnecessary phototherapy may be prudent.

External Validation of Early Weight Loss Nomograms for Exclusively Breastfed Newborns

INTRODUCTION

Nomograms that show hour-by-hour percentiles of weight loss during the birth hospitalization were recently developed to aid clinical care of breastfeeding newborns. The nomograms for breastfed neonates were based on a sample of 108,907 newborns delivered at 14 Kaiser Permanente medical centers in Northern California (United States). The objective of this study was to externally validate the published nomograms for newborn weight loss using data from a geographically distinct population.

MATERIALS AND METHODS

Data were compiled from the Penn State Milton S. Hershey Medical Center located in Hershey, PA. For singleton neonates delivered at ≥36 weeks of gestation between January 2013 and September 2014, weights were obtained between 6 hours and 48 hours (vaginal delivery) or 60 hours (cesarean delivery) for neonates who were exclusively breastfeeding. Quantile regression methods appropriate for repeated measures were used to estimate 50th, 75th, 90th, and 95th percentiles of weight loss as a function of time after birth. These percentile estimates were compared with the published nomograms.

RESULTS

Of the 1,587 newborns who met inclusion criteria, 1,148 were delivered vaginally, and 439 were delivered via cesarean section. These newborns contributed 1,815 weights for vaginal deliveries (1.6 per newborn) and 893 weights for cesarean deliveries (2.0 per newborn). Percentile estimates from this Penn State sample were similar to the published nomograms. Deviations in percentile estimates for the Penn State sample were similar to deviations observed after fitting the same model separately to each medical center that made up the Kaiser Permanente sample.

CONCLUSIONS

The published newborn weight loss nomograms for breastfed neonates were externally validated in a geographically distinct population.

Incidence of Dravet Syndrome in a US Population

OBJECTIVE

De novo mutations of the gene sodium channel 1α (SCN1A) are the major cause of Dravet syndrome, an infantile epileptic encephalopathy. US incidence of DS has been estimated at 1 in 40 000, but no US epidemiologic studies have been performed since the advent of genetic testing.

METHODS

In a retrospective, population-based cohort of all infants born at Kaiser Permanente Northern California during 2007-2010, we electronically identified patients who received ≥2 seizure diagnoses before age 12 months and who were also prescribed anticonvulsants at 24 months. A child neurologist reviewed records to identify infants who met 4 of 5 criteria for clinical Dravet syndrome: normal development before seizure onset; ≥2 seizures before age 12 months; myoclonic, hemiclonic, or generalized tonic-clonic seizures; ≥2 seizures lasting >10 minutes; and refractory seizures after age 2 years. SCN1A gene sequencing was performed as part of routine clinical care.

RESULTS

Eight infants met the study criteria for clinical Dravet syndrome, yielding an incidence of 1 per 15 700. Six of these infants (incidence of 1 per 20 900) had a de novo SCN1A missense mutation that is likely to be pathogenic. One infant had an inherited SCN1A variant that is unlikely to be pathogenic. All 8 experienced febrile seizures, and 6 had prolonged seizures lasting >10 minutes by age 1 year.

CONCLUSIONS

Dravet syndrome due to an SCN1A mutation is twice as common in the United States as previously thought. Genetic testing should be considered in children with ≥2 prolonged febrile seizures by 1 year of age.

Early weight loss nomograms for formula fed newborns

OBJECTIVES

To develop nomograms depicting percentiles of weight loss by hour of age for both vaginal and cesarean-delivered newborns who are exclusively formula fed.

METHODS

Data regarding delivery mode, race/ethnicity, feeding type, and weights were extracted from electronic medical records of the birth hospitalization at 14 Kaiser Permanente Northern California hospitals between 2009 and 2013. Newborns whose first feeding was formula from a cohort of 161 471 healthy, term, singleton neonates born at ≥36 weeks' gestation between 2009 and 2013 were identified. Quantile regression was used to create nomograms stratified according to delivery mode; percentiles of weight loss were estimated as a function of time among formula-fed neonates. Weights measured subsequent to any breast milk feeding were excluded. Percentiles were determined through 48 and 72 hours of age for those born vaginally and via cesarean delivery, respectively.

RESULTS

A total of 7075 formula-fed newborns had weights recorded; 4525 were delivered vaginally, and 2550 were born via cesarean delivery. The median weight loss was 2.9% at 48 hours after vaginal delivery; weight loss>7% was rare. For cesarean-delivered neonates, median weight losses at 48 and 72 hours were 3.7% and 3.5%, respectively; weight loss>8% was rare.

CONCLUSIONS

For newborns who are formula fed, these results provide nomograms depicting percentiles of weight loss according to mode of delivery. These plots can be used to classify early weight loss according to percentile and may enable early identification of feeding difficulties or other neonatal morbidities.

Risk of Sensorineural Hearing Loss and Bilirubin Exchange Transfusion Thresholds

BACKGROUND AND OBJECTIVES

High bilirubin levels are associated with sensorineural hearing loss (SNHL). However, few large studies of relative and excess risk exist. We sought to quantify the risk of SNHL in newborns who had bilirubin levels at or above American Academy of Pediatrics exchange transfusion thresholds (ETT).

METHODS

Infants born at ≥35 weeks gestation in 15 Kaiser Permanente Northern California hospitals from 1995-2011 were eligible (N = 525 409). We used a nested double cohort design. The exposed cohort included subjects with ≥1 bilirubin level at or above ETT. The unexposed cohort was a 3.6% random sample of subjects with all bilirubin levels below ETT (10 unexposed per exposed). An audiologist, blinded to bilirubin levels, reviewed the charts of children in whom SNHL had been diagnosed before age 8 years to confirm the diagnosis. We calculated Cox proportional hazard ratios for time to diagnosis of SNHL.

RESULTS

SNHL was confirmed in 11 (0.60%) of the 1834 exposed subjects and in 43 (0.23%) of the 19 004 unexposed. Only bilirubin levels ≥10 mg/dL above ETT were associated with a statistically significant increased risk of SNHL (hazard ratio: 36 [95% confidence interval (CI): 13 to 101]). Likewise, only bilirubin levels ≥35 mg/dL were associated with a statistically significant increased risk of SNHL (hazard ratio: 91 [95% CI: 32 to 255]). For subjects with total serum bilirubin levels 0 to 4.9 mg/dL above ETT, the upper limit of the 95% CI for excess risk was 0.5%.

CONCLUSIONS

Only bilirubin levels well above ETT were associated with SNHL. At lower bilirubin levels, the excess risk of SNHL was low.

Perioperative chemotherapy in the treatment of osteosarcoma: a 26-year single institution review

Background

Chemotherapy in the multimodality treatment of osteosarcoma has improved survival. Reported outcomes on adult patients are limited. Poor necrosis rates post neoadjuvant chemotherapy (NAC) is considered an adverse prognostic factor and attempts have been made to improve survival in this group.

Patients and methods

Adult and young adult patients diagnosed with osteosarcoma between January 1986 and August 2012 were retrospectively reviewed. Patients identified were stratified according to stage (localised or metastatic) and age (≤40 and >40 years). Event free survival (EFS) and overall survival (OS) outcomes were determined. In patients with localised disease ≤40 years, survival was assessed according to necrosis rates post NAC (<90 and ≥90%). NAC consisted of two cycles of methotrexate alternating with doxorubicin/cisplatin (MAP) followed by definitive surgery. Those with ≥90% tumour necrosis continued on MAP. Patients with <90% necrosis received ifosfamide and etoposide (IE) post operatively.

Results

A total of 108 patients were reviewed and 97 were included. Median age was 23 years (range 16–75) and 70% of patients were male. Five year EFS and OS across all groups was 57% and 63% respectively. Of the patients with localised disease (N = 81), 5-year overall survival (OS), with a median follow up of 7 years (2–26) was 70% (p < 0.0001). Patients aged 16–40 (N = 68) with localised osteosarcoma had a significantly improved 5-year OS (74%) compared to those >40 years (N = 13) (42%) (p = 0.004). Of the 68 patients with localised osteosarcoma ≤40 years, 62 were evaluated according to necrosis rates post MAP. In 33 patients who achieved ≥90% necrosis and continued MAP, 5-year OS was 82%. In 29 patients who had <90% tumour necrosis and received adjuvant IE, 5-year OS was 68% (p = 0.15). Multivariate analysis confirmed age and stage as prognostic factors but not poor necrosis rates in our treated population.

Conclusions

Long-term survival outcomes in a predominantly adult Irish population are similar to large reported trials. Age and stage at diagnosis are prognostic. Postoperative ifosfamide/etoposide alone in patients with poor necrosis rates is a feasible regimen, but its role in the adjuvant setting remains uncertain.

Electronic supplementary material

The online version of this article (doi:10.1186/s13569-015-0032-0) contains supplementary material, which is available to authorized users.

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.

Breast cancer detection among Irish BRCA1 & BRCA2 mutation carriers: a population-based study

BACKGROUND

High-risk breast cancer screening for BRCA1/2 mutation carriers with clinical breast exam, mammography and MRI has reported sensitivity of 100 %, but BRCA1/2 mutation carriers still present with interval cancers.

AIMS

We investigated the presentation and screening patterns of an Irish cohort of BRCA1/2 mutation carriers with breast cancer.

MATERIALS AND METHODS

BRCA1/2 mutation carriers with breast cancer were identified in this retrospective cohort study. Records were reviewed for BRCA1/2 mutation status, demographics, screening regimen, screening modality, stage and histology at diagnosis.

RESULTS

Fifty-three cases of breast cancer were diagnosed between 1968 and 2010 among 60 Irish hereditary breast ovarian cancer (HBOC) families. In 50 of 53 women, the diagnosis of breast cancer predated the identification of BRCA1/2 mutations. Breast cancer detection method was identified in 47 % of patients (n = 25): 80 % (n = 20) by clinical breast exam (CBE), 12 % by mammography (n = 3), 8 % by MRI (n = 2). Fourteen women (26 %) developed a second breast cancer. Ten of these patients (71 %) were involved in regular screening; 50 % were detected by screening mammography, 20 % by MRI and 30 % by CBE alone. Six patients (43 %) had a change in morphology from first to second breast cancers. There was no change in hormone receptor status between first and second breast cancers.

CONCLUSION

In this cohort of Irish BRCA1/2 mutation carriers, compliance with screening was inconsistent. There was a 30 % incidence of interval cancers occurring in women in high-risk screening. Preventive surgery may be a more effective risk reduction strategy for certain high-risk women.

Early weight loss nomograms for exclusively breastfed newborns

BACKGROUND

The majority of newborns are exclusively breastfed during the birth hospitalization, and weight loss is nearly universal for these neonates. The amount of weight lost varies substantially among newborns with higher amounts of weight loss increasing risk for morbidity. No hour-by-hour newborn weight loss nomogram exists to assist in early identification of those on a trajectory for adverse outcomes.

METHODS

For 161 471 term, singleton neonates born at ≥36 weeks' gestation at Northern California Kaiser Permanente hospitals in 2009-2013, data were extracted from the birth hospitalization regarding delivery mode, race/ethnicity, feeding type, and weights from electronic records. Quantile regression was used to create nomograms stratified by delivery mode that estimated percentiles of weight loss as a function of time among exclusively breastfed neonates. Weights measured subsequent to any nonbreastmilk feeding were excluded.

RESULTS

Among this sample, 108 907 newborns had weights recorded while exclusively breastfeeding with 83 433 delivered vaginally and 25 474 delivered by cesarean. Differential weight loss by delivery mode was evident 6 hours after delivery and persisted over time. Almost 5% of vaginally delivered newborns and >10% of those delivered by cesarean had lost ≥10% of their birth weight 48 hours after delivery. By 72 hours, >25% of newborns delivered by cesarean had lost ≥10% of their birth weight.

CONCLUSIONS

These newborn weight loss nomograms demonstrate percentiles for weight loss by delivery mode for those who are exclusively breastfed. The nomograms can be used for early identification of neonates on a trajectory for greater weight loss and related morbidities.

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.

ΔNp63α activates CD82 metastasis suppressor to inhibit cancer cell invasion

P63 is a p53 family member involved in multiple facets of biology, including embryonic development, cell proliferation, differentiation, survival, apoptosis, senescence and aging. The p63 gene encodes multiple protein isoforms either with (TAp63) or without (ΔNp63) the N-terminal transactivation domain. Amounting evidence suggests that p63 can function as a tumor suppressor, yet the precise molecular mechanisms, and particularly the specific roles of TAp63 and ΔNp63 in cancer progression, are still largely unclear. Here, we demonstrated that ΔNp63α, the predominant isoform expressed in epithelial cells and squamous cell carcinomas, inhibits cell invasion. Affymetrix gene expression profiling, combined with gain- and loss-of-function analyses and chromatin immunoprecipitation, indicated that cluster of differentiation 82 (CD82), a documented metastasis suppressor, is a direct transcriptional target of ΔNp63α. Expression of ΔNp63α inhibited outgrowth in Matrigel and cancer cell invasion, which was largely reversed by specific ablation of CD82. Conversely, ΔNp63α knockdown led to increased cell invasion, which was reversed by ectopic expression of CD82. Moreover, inhibition of glycogen synthase kinase-3β (GSK3β) by either pharmacological inhibitors or by RNA interference resulted in the downregulation of ΔNp63α and CD82 expression, concomitant with increased cell invasion, independently of β-catenin. Furthermore, decreased expression of p63 and CD82 is correlated with cancer progression. Taken together, this study reveals that ΔNp63α upregulates CD82 to inhibit cell invasion, and suggests that GSK3β can regulate cell invasion by modulating the ΔNp63α–CD82 axis.

Prevalence and neonatal factors associated with autism spectrum disorders in preterm infants

OBJECTIVES

To determine the prevalence of autism spectrum disorders (ASD) across gestational age, examine the risk of ASD by gestational age controlling for other risk factors, and identify potential risk factors in the neonatal intensive care unit.

STUDY DESIGN

A retrospective cohort of infants born at ≥ 24 weeks between January 1, 2000, and December 31, 2007 at 11 Kaiser Permanente Northern California hospitals (n = 195,021). ASD cases were defined by a diagnosis made at a Kaiser Permanente ASD evaluation center, by a clinical specialist, or by a pediatrician. Cox proportional hazards regression models were used to evaluate the association between gestational age and ASD as well as potential risk factors in the neonatal intensive care unit and ASD.

RESULTS

The prevalence of ASD in infants <37 weeks was 1.78% compared with 1.22% in infants born ≥ 37 weeks (P < .001). Compared with term infants, infants born at 24-26 weeks had an adjusted hazard ratio (HR) for a diagnosis of ASD of 2.7 (95% CI 1.5-5.0). Infants born at 27-33 weeks (adjusted HR 1.4, 95% CI 1.1-1.8) and 34-36 weeks (adjusted HR 1.3, 95% CI 1.1-1.4) were also at increased risk. High frequency ventilation and intracranial hemorrhage were associated with ASD in infants < 34 weeks.

CONCLUSIONS

ASD was ~ 3 times more prevalent in infants <27 weeks compared with term infants. Each week of shorter gestation was associated with an increased risk of ASD. High frequency ventilation and intracranial hemorrhage were associated with ASD among infants <34 weeks.

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.

Adherence to Immunoprophylaxis Regimens for Respiratory Syncytial Virus Infection in Insured and Medicaid Populations

BACKGROUND

Immunoprophylaxis is the only pharmaceutical intervention for mitigating respiratory syncytial virus (RSV) infection. Patient level data on adherence to American Academy of Pediatrics (AAP) immunoprophylaxis recommendations are limited. This study characterizes adherence to AAP guidelines in privately insured and Medicaid populations.

METHODS

We performed a retrospective birth cohort study of 211 174 privately insured children in Northern California; and 458 837 publicly insured children in Tennessee born between January 1, 1996 and December 31, 2008. Adherence to the AAP guideline was defined for eligible infants as the number of doses of RSV immunoprophylaxis administered over the number recommended for 4 mutually exclusive eligibility groups: chronic lung disease, prematurity <29 weeks, prematurity <32 weeks, and other eligibility.

RESULTS

We identified 3456 California (Kaiser Permanente Northern California [KPNC]) and 12 251 Tennessee (Tennessee Medicaid [TennCare]) infants meeting AAP eligibility criteria. Immunoprophylaxis administration increased over the study period, from 15% for all eligible groups in 1998 to 54% in 2007. Adherence was highest among babies with chronic lung disease (KPNC 67% and TennCare 55%). Nonadherence (0% adherence) was greatest among infants of African American mothers (adjusted odds ratio [AOR] = 1.32; 95% confidence interval [CI] = .98-1.78); those with mothers with less than a high school education (AOR = 1.58; CI = 1.09-2.30) in KPNC; and in infants of Hispanic mothers in TennCare (AOR = 1.65; CI = 1.24-2.20). In KPNC, 0.11% of ineligible term infants and 5% of ineligible premature infants received immunoprophylaxis; the corresponding proportions in TennCare were 1% and 11%.

CONCLUSIONS

Overall adherence with AAP guidelines has increased over time. Considerable overuse and underuse of immunoprophylaxis are evident with identifiable risk groups to target for improvement.

Policy challenges for child welfare in the new century

Recent changes in public policy reflect increased efforts to scapegoat poor women and children and to polarize the objectives of child protection and family preservation. This article challenges various stakeholders in the child welfare field to move beyond the quick-fix solutions and bureaucratic overregulation precipitated by horror stories of child abuse in the media. The new century presents an opportunity to pursue differential intervention strategies that protect children while empowering poor families and communities.

Intravital microscopy: a new in vivo technique for visualizing and quantifying effects of regulatory peptides on choledochoduodenal junction motility

Using intravital microscopy, we studied the in vivo effects of regulatory peptides on choledochoduodenal junction motility in guinea pigs. During basal and hormone-stimulated periods, intravital microscopy documented rhythmic, asymmetrical, "milking" contractions of the sphincter ductus choledochi (SDC) which occurred independent of sphincter ampullae (SA) contractions or were followed by SA contractions. Cholecystokinin octapeptide (CCK-8) (greater than or equal to 0.01 micrograms/kg) increased the frequency of SDC contractions and at higher doses (greater than or equal to 0.1 microgram/kg) increased the frequency of SA contractions. Pentagastrin (greater than or equal to 1.0 microgram/kg) and secretin (10 micrograms/kg) decreased the contraction frequencies of both sphincters. Biliary manometry demonstrated similar effects of these peptides on the frequency of the SDC and SA contractions, but also showed that CCK-8 (0.1 microgram/kg) increased the amplitude of SDC and SA contractions while pentagastrin (1 microgram/kg) decreased the amplitude of only SDC contractions. Tetrodotoxin and atropine did not affect hormone-induced changes in frequency, but tetrodotoxin reduced the increase in amplitude of contraction caused by CCK-8. We concluded that intravital microscopy provides a sensitive, in vivo technique to visualize and quantify the complex motility of a small structure like the choledochoduodenal junction.

Biliary motility: postnatal changes in guinea pigs

Intravital microscopy, a new in vivo technique, documented age-dependent changes in choledochoduodenal junction motility in male guinea pigs. In the guinea pig, the choledochoduodenal junction served as a pump that actively emptied its luminal contents into the duodenum. In the neonates (less than or equal to 1 wk old), this choledochoduodenal junction pump was not fully developed. Unlike the older guinea pigs, some neonates had an incompetent sphincter ductus choledochi (SDC) allowing retrograde flow of bile during ampullary contractions. While fasting, neonates had decreased frequency of SDC (1.2 +/- 0.4 contractions/min) and ampullary (0.1 +/- 0.1 contractions/min) contractions as compared to juveniles (4-6 wk old) (SDC = 6.4 +/- 1.0; ampulla = 1.2 +/- 0.2 contractions/min) and adults (greater than 1 yr old) (SDC = 6.7 +/- 1.6; 0.8 +/- 0.2 contractions/min). Following a meal (Ensure), unlike older guinea pigs, the neonate did not have a significant increased duration and decreased frequency of SDC contractions. Altered neonatal SDC motility correlated with an incompletely developed SDC including decreased muscle mass and mucosal thickness. By 4 wk of age, choledochoduodenal junction motility was similar to that of the adult. These developmental alterations in junctional motility and structure may affect the flow of bile into the duodenum contributing to physiologic cholestasis and decreased intraduodenal bile acids seen in neonates.

The functional competence of uterine-derived polymorphonuclear neutrophils (PMN) from mares resistant and susceptible to chronic uterine infection: a sequential migration analysis

The functional competence of uterine-derived polymorphonuclear neutrophils (PMNs) from 28 mares was measured for migration responsiveness by use of a chamber (filter) assay. Uterine infection was induced with Streptococcus zooepidemicus in mares considered resistant to chronic uterine infection (Grade I). In sequential analysis of uterine flushings obtained from these mares 5, 12, 15, 20, and 25 h after infection was induced, PMNs showed an initial rise at 12 h (from 5), then a general decline in migration response and in concentration of cells per ml from 12 through 25 h post-inoculation. In contrast, PMNs obtained from the uterine flushings from mares considered susceptible to chronic uterine infection (Grade III) demonstrated premature migration dysfunction 12 h after infection. Subsequent increases in functional competence of the PMNs were demonstrated at 15 and again at 25 h after induced infection. The concentration of uterine PMNs per ml from mares considered susceptible to chronic endometritis remained elevated from 12 through 25 h after inoculation, which suggests a possible continued recruitment of new PMNs from the peripheral circulation. The results of this study suggest that uterine-derived PMNs obtained from mares susceptible to chronic uterine infection have a compromised ability to migrate. This dysfunction may play an important role in rendering the endometrium (uterus) susceptible to chronic endometritis.

Phagocytic and killing capacities of uterine-derived polymorphonuclear leukocytes from mares resistant and susceptible to chronic endometritis

The host defense competence of uterine-derived polymorphonuclear leukocytes (PMN) from mares considered resistant (grade I uteri) and susceptible (grade III uteri) to chronic endometritis was evaluated for phagocytic and killing (bactericidal) capacities, using a fluorochrome assay. Peripheral blood PMN from noncategorized mares and from grade I and grade III mares were used as controls. Uterine-derived PMN from mares with grade I uteri were functionally competent for phagocytosis and killing of Candida albicans, whereas uterine-derived PMN from mares with grade III uteri had significantly less phagocytic and killing capacities (P greater than or equal to 0.0001). Results of the present study, together with data obtained from chemotactic responsiveness and deformability assays of a previous study, indicated an overall deficiency in the host defense mechanism of uterine-derived PMN from mares with grade III uteri obtained 12 hours after induced Streptococcus zooepidemicus infection. This deficiency may account for the susceptibility of mares with grade III uteri to chronic endometritis.

Comparison of peripheral blood and uterine-derived polymorphonuclear leukocytes from mares resistant and susceptible to chronic endometritis: chemotactic and cell elastimetry analysis

The functional competence of peripheral blood and uterine-derived polymorphonuclear leukocytes (PMN) from 12 mares were analyzed for chemotactic responsiveness using a chemotactic chamber (filter) assay and for deformability by cell elastimetry analysis. Peripheral blood PMN obtained from control mares and from 8 mares experimentally inoculated via the uterus with 1 x 10(9) Streptococcus zooepidemicus had similar normal chemotactic responsiveness and were highly deformable before and at 12 hours after inoculation. Uterine PMN obtained 12 hours after uterine inoculation with S zooepidemicus from resistant mares were not as deformable as peripheral blood PMN, but were within normal functional limits. The chemotactic responsiveness of uterine PMN from these mares was normal. Uterine PMN obtained from mares considered susceptible to endometritis 12 hours after uterine infection did not have chemotactic responsiveness and were nondeformable. The results indicated profound differences in the functional competence of uterine PMN between mares considered resistant and susceptible to chronic endometritis.

Abnormal maturation of sleep states in infants with aborted sudden infant death syndrome

The time spent in REM, quiet, and indeterminate sleep was computed in 13 aborted SIDS infants and compared to that spent in the same sleep states, in 19 normal infants. Aborted sudden infant death syndrome (SIDS) infants were studied within a week of their aborted SIDS episode and subsequently at monthly intervals through the age of 4 months. Normal infants were studied at 1, 2, 3, and 4 months of age. Sleep staging was performed by two independent observers using electroencephalogram, electrooculogram, electromyogram and behavioral criteria. Although there was an increase in the percentage of time spent in quiet sleep with age in both normal and aborted SIDS infants, the significantly greater regression coefficients in normal infants (6.3 versus 2.9; P less than 0.01) indicate that there are differences in the two groups and suggest a maturational abnormality or delay in sleep state distribution in the aborted SIDS infants.