Integrating Data Across Multiple Sites in the Northeastern United States to Examine Associations Between a Prenatal Metal Mixture and Child Cognition

We applied a novel hierarchical Bayesian weighted quantile sum (HBWQS) regression to combine data across 3 study sites to examine associations between prenatal exposure to metals and cognitive functioning in childhood. Data from 326 mother-child dyads enrolled in an ongoing cohort study, the Programming of Intergenerational Stress Mechanisms (PRISM) Study, based in New York, New York (recruitment in 2013-2020) and Boston, Massachusetts (recruitment 2011-2013), and the First Thousand Days of Life (FTDL) cohort study (recruitment 2012-2019), based in northern Virginia, were used. Arsenic, cadmium, manganese, lead, and antimony were measured in urine collected during pregnancy. Cognitive functioning was assessed in children aged 3-11 years using the National Institutes of Health Toolbox Cognition Battery. The HBWQS regression showed a negative association between the urinary metal mixture and the Cognition Early Childhood Composite Score in the PRISM New York City (β = -3.67, 95% credible interval (CrI): -7.61, -0.01) and FTDL (β = -3.76, 95% CrI: -7.66, -0.24) samples, with a similar trend in the PRISM Boston sample (β = -3.24, 95% CrI: -6.77, 0.144). We did not detect these associations in traditionally pooled models. HBWQS regression allowed us to account for site heterogeneity and detect associations between prenatal metal-mixture exposure and cognitive outcomes in childhood. Given the ubiquity of metals exposure, interventions aimed at reducing prenatal exposure may improve cognitive outcomes in children. This article is part of a Special Collection on Environmental Epidemiology.

Prenatal exposure to PM2.5 and childhood cognition: Accounting for between-site heterogeneity in a pooled analysis of ECHO cohorts in the Northeastern United States

BACKGROUND

Emerging studies have investigated the adverse health effects of PM_2.5 using data from multiple cohorts, and results often are not generalizable across cohorts. We aimed to assess associations between prenatal PM_2.5 and childhood cognition in two U.S. cohorts while accounting for between-site heterogeneity.

METHODS

Analyses included 348 mother-child dyads enrolled in the dual site (New York City and Boston) PRogramming of Intergenerational Stress Mechanisms (PRISM) cohort and in the First Thousand Days of Life (FTDL) study (Northern Virginia) participating in the Environmental influences on Child Health Outcomes (ECHO) national consortium. Residential prenatal PM_2.5 exposure was estimated using a validated satellite-based model and childhood cognition was measured using the NIH Toolbox Cognition Battery at three to eight years of age. We used a log-linear model applied to contingency tables formed by cross-classifying covariates by site to examine between-site heterogeneity using 3^rd trimester PM_2.5 exposure, age-corrected cognition scores, and covariates potentially causing heterogeneities. Multivariable linear regression models informed by the combinability analysis were used to estimate the coefficients and 95% confidence intervals (CIs) for the association between 3^rd trimester PM_2.5 exposure and age-corrected cognition scores (mean = 100, SD = 15).

RESULTS

The log-linear model indicated that inter-study associations were similar between PRISM-NYC and FTDL, which were different from those in PRISM-Boston. Accordingly, we combined the data of PRISM-NYC and FTDL cohorts. We observed associations between 3^rd trimester PM_2.5 and cognition scores, findings were varying by site, childsex, and test. For example, a 1 μg/m³ increase of 3^rd trimester PM_2.5 was associated with -4.35 (95% CI = -8.73, -0.25) mean early childhood cognition scores in females in PRISM-Boston. In the pooled NYC + FTDL site, the association between PM_2.5 and childhood cognition may be modified by maternal education and urbanicity.

CONCLUSIONS

We found associations between prenatal PM_2.5 and impaired childhood cognition. Since multi-site analyses are increasingly conducted, our findings suggest the needed awareness of between-site heterogeneity.

Regional and sociodemographic differences in average BMI among US children in the ECHO program

OBJECTIVE

The aim of this study was to describe the association of individual-level characteristics (sex, race/ethnicity, birth weight, maternal education) with child BMI within each US Census region and variation in child BMI by region.

METHODS

This study used pooled data from 25 prospective cohort studies. Region of residence (Northeast, Midwest, South, West) was based on residential zip codes. Age- and sex-specific BMI z scores were the outcome.

RESULTS

The final sample included 14,313 children with 85,428 BMI measurements, 49% female and 51% non-Hispanic White. Males had a lower average BMI z score compared with females in the Midwest (β = -0.12, 95% CI: -0.19 to -0.05) and West (β = -0.12, 95% CI: -0.20 to -0.04). Compared with non-Hispanic White children, BMI z score was generally higher among children who were Hispanic and Black but not across all regions. Compared with the Northeast, average BMI z score was significantly higher in the Midwest (β = 0.09, 95% CI: 0.05 to 0.14) and lower in the South (β = -0.12, 95% CI: -0.16 to -0.08) and West (β = -0.14, 95% CI: -0.19 to -0.09) after adjustment for age, sex, race/ethnicity, and birth weight.

CONCLUSIONS

Region of residence was associated with child BMI z scores, even after adjustment for sociodemographic characteristics. Understanding regional influences can inform targeted efforts to mitigate BMI-related disparities among children.

Maternal Confidence and Emergency Department Utilization Among Infants

OBJECTIVES

To determine if maternal confidence affects emergency department (ED) utilization in the first year of life.

METHODS

This retrospective cohort study examined the Maternal Confidence Questionnaire responses from a longitudinal birth cohort study and ED visits for these subjects across all Inova hospitals from January 2012 to July 2017 for full-term children 12 months or younger at the time of visit. Using logistic regression, maternal confidence, maternal race/ethnicity, age, education, parity, and insurance were evaluated against Emergency Severity Index acuity levels and ED visit frequency.

RESULTS

Of 2429 participants in the longitudinal study, 316 subjects visited the ED and met inclusion criteria. Medicaid status was the main factor associated with any ED visit. Low maternal confidence did not correlate with more frequent or nonurgent ED visits. Higher maternal confidence scores were seen in Hispanic or Latino mothers and mothers with parity greater than 1. Hispanic or Latino mothers were more likely to have Medicaid and more likely to bring their child to the ED. Mothers with college education had lower maternal confidence scores, were less likely to visit the ED, but had higher acuity level visits.

CONCLUSIONS

Low maternal confidence did not correlate with frequent ED visits or nonurgent visits. Medicaid status was the main factor associated with any ED visit. Hispanic or Latino mothers had higher maternal confidence scores, were more likely to have Medicaid and more likely to bring their child to the ED.

Racial and geographic variation in effects of maternal education and neighborhood-level measures of socioeconomic status on gestational age at birth: Findings from the ECHO cohorts

Preterm birth occurs at excessively high and disparate rates in the United States. In 2016, the National Institutes of Health (NIH) launched the Environmental influences on Child Health Outcomes (ECHO) program to investigate the influence of early life exposures on child health. Extant data from the ECHO cohorts provides the opportunity to examine racial and geographic variation in effects of individual- and neighborhood-level markers of socioeconomic status (SES) on gestational age at birth. The objective of this study was to examine the association between individual-level (maternal education) and neighborhood-level markers of SES and gestational age at birth, stratifying by maternal race/ethnicity, and whether any such associations are modified by US geographic region. Twenty-six ECHO cohorts representing 25,526 mother-infant pairs contributed to this disseminated meta-analysis that investigated the effect of maternal prenatal level of education (high school diploma, GED, or less; some college, associate's degree, vocational or technical training [reference category]; bachelor's degree, graduate school, or professional degree) and neighborhood-level markers of SES (census tract [CT] urbanicity, percentage of black population in CT, percentage of population below the federal poverty level in CT) on gestational age at birth (categorized as preterm, early term, full term [the reference category], late, and post term) according to maternal race/ethnicity and US region. Multinomial logistic regression was used to estimate odds ratios (OR) and 95% confidence intervals (CIs). Cohort-specific results were meta-analyzed using a random effects model. For women overall, a bachelor's degree or above, compared with some college, was associated with a significantly decreased odds of preterm birth (aOR 0.72; 95% CI: 0.61-0.86), whereas a high school education or less was associated with an increased odds of early term birth (aOR 1.10, 95% CI: 1.00-1.21). When stratifying by maternal race/ethnicity, there were no significant associations between maternal education and gestational age at birth among women of racial/ethnic groups other than non-Hispanic white. Among non-Hispanic white women, a bachelor's degree or above was likewise associated with a significantly decreased odds of preterm birth (aOR 0.74 (95% CI: 0.58, 0.94) as well as a decreased odds of early term birth (aOR 0.84 (95% CI: 0.74, 0.95). The association between maternal education and gestational age at birth varied according to US region, with higher levels of maternal education associated with a significantly decreased odds of preterm birth in the Midwest and South but not in the Northeast and West. Non-Hispanic white women residing in rural compared to urban CTs had an increased odds of preterm birth; the ability to detect associations between neighborhood-level measures of SES and gestational age for other race/ethnic groups was limited due to small sample sizes within select strata. Interventions that promote higher educational attainment among women of reproductive age could contribute to a reduction in preterm birth, particularly in the US South and Midwest. Further individual-level analyses engaging a diverse set of cohorts are needed to disentangle the complex interrelationships among maternal education, neighborhood-level factors, exposures across the life course, and gestational age at birth outcomes by maternal race/ethnicity and US geography.

Prenatal and Peripartum Exposure to Antibiotics and Cesarean Section Delivery Are Associated with Differences in Diversity and Composition of the Infant Meconium Microbiome

The meconium microbiome may provide insight into intrauterine and peripartum exposures and the very earliest intestinal pioneering microbes. Prenatal antibiotics have been associated with later obesity in children, which is thought to be driven by microbiome dependent mechanisms. However, there is little data regarding associations of prenatal or peripartum antibiotic exposure, with or without cesarean section (CS), with the features of the meconium microbiome. In this study, 16S ribosomal RNA gene sequencing was performed on bacterial DNA of meconium samples from 105 infants in a birth cohort study. After multivariable adjustment, delivery mode (p = 0.044), prenatal antibiotic use (p = 0.005) and peripartum antibiotic use (p < 0.001) were associated with beta diversity of the infant meconium microbiome. CS (vs. vaginal delivery) and peripartum antibiotics were also associated with greater alpha diversity of the meconium microbiome (Shannon and Simpson, p < 0.05). Meconium from infants born by CS (vs. vaginal delivery) had lower relative abundance of the genus Escherichia (p < 0.001). Prenatal antibiotic use and peripartum antibiotic use (both in the overall analytic sample and when restricting to vaginally delivered infants) were associated with differential abundance of several bacterial taxa in the meconium. Bacterial taxa in the meconium microbiome were also differentially associated with infant excess weight at 12 months of age, however, sample size was limited for this comparison. In conclusion, prenatal and peripartum antibiotic use along with CS delivery were associated with differences in the diversity and composition of the meconium microbiome. Whether or not these differences in the meconium microbiome portend risk for long-term health outcomes warrants further exploration.

Association of Ancestral Genetic Admixture and Excess Weight at Twelve Months of Age

Background/Objective: Understanding the influence of genetically determined ancestry may give insight into the disparities of obesity seen in different ethnic groups beginning at a very early age. Aim: To investigate the relationship between children's ancestral genetic proportions and excess weight at 12 months of age. Methods: Eight hundred twenty-one 12-month-old children were included in this cross-sectional study. Their genetic admixture was estimated using the ancestry and kinship tool kit by projecting the samples into the 1000 Genomes principal component database. Weight-for-length percentile (WFLP) at 12 months of age was categorized as <95th percentile or ≥95th percentile. Multiple logistic regression analysis was performed to calculate odds ratios (ORs) with 95% confidence intervals (CIs) for the association of admixture proportions, including European (EUR), admixed American (AMR), African (AFR), South Asian (SAS), and East Asian (EAS) populations, with WFLP categories, adjusting for maternal education, birth weight, frequency of breastfeeding, and juice consumption. Results: Eight hundred twenty-one children were included; WFLP <95th percentile = 671 (81.7%) and WFLP ≥95th percentile = 150 (18.3%). Crude ORs showed that the EUR admixture was protective [OR 0.45 (95% CI 0.27-0.74)], whereas AMR [OR 3.85 (95% CI 1.92-7.70)] and AFR [OR 5.70 (95% CI 2.19-14.85)] admixtures were positively associated with excess weight. After adjusting for confounding variables, only the AFR admixture was associated with WFLP ≥95th percentile [OR 7.38 (95% CI 2.31-23.59)]. Conclusions: AFRs remain associated with early excess weight after accounting for confounding variables, suggesting that this ancestral genetic background may contribute to the differences seen in early childhood obesity.

Clinical and social factors associated with excess weight in Hispanic and non-Hispanic White children

BACKGROUND

Hispanic children are disproportionately affected by obesity, with this disparity starting at a young age, and there is a paucity of data comparing factors associated with excess weight in the first year of life in Hispanic vs. non-Hispanic populations.

METHODS

Excess weight was defined as weight-for-length ≥95th percentile. The associations of potential risk factors were compared by ethnicity stratification.

RESULTS

Of the 1009 children, 302 (30.0%) were Hispanic and 707 (70.0%) were non-Hispanic White. The rate of excess weight was 30.1% and 13.6% among Hispanic and non-Hispanic White children, respectively. Factors associated with excess weight for non-Hispanic White children were higher than recommended weight gain during pregnancy (odds ratio (OR) 1.8 (1.2-3.1)), higher paternal body mass index (BMI) (OR 1.1 (1.02-1.15)), higher birth weight (OR 1.001 (1.001-1.002)), and lower breast milk feedings at 6 months (OR 0.98 (0.96-0.98)). Factors associated with excess weight for Hispanic children were lower maternal education (OR 2.37 (1.1-4.5)) and lower breast milk feedings at 6 months (OR 0.98 (0.96-0.99)).

CONCLUSION

There are differential risk factors associated with excess weight at 12 months between Hispanic and non-Hispanic White children. Identification of differential factors in different ethnicities may allow for more targeted anticipatory guidance reduce obesity in at-risk populations.

Comparison of Infant Gut and Skin Microbiota, Resistome and Virulome Between Neonatal Intensive Care Unit (NICU) Environments

Background: There is a growing move to provide care for premature infants in a single family, private room neonatal intensive care unit (NICU) in place of the traditional shared space, open bay NICU. The resultant effect on the developing neonatal microbiota is unknown.

Study Design: Stool and groin skin swabs were collected from infants in a shared-space NICU (old NICU) and a single-family room NICU (new NICU) on the same hospital campus. Metagenomic sequencing was performed and data analyzed by CosmosID bioinformatics software package.

Results: There were no significant differences between the cohorts in gestational age, length of stay, and delivery mode; infants in the old NICU received significantly more antibiotics (p = 0.03). Differentially abundant antimicrobial resistance genes and virulence associated genes were found between the cohorts in stool and skin, with more differentially abundant antimicrobial resistance genes in the new NICU. The entire bacterial microbiota analyzed to the genus level significantly differed between cohorts in skin (p = 0.0001) but not in stool samples. There was no difference in alpha diversity between the two cohorts. DNA viruses and fungi were detected but did not differ between cohorts.

Conclusion: Differences were seen in the resistome and virulome between the two cohorts with more differentially abundant antimicrobial resistance genes in the new NICU. This highlights the influence that different NICU environments can have on the neonatal microbiota. Whether the differences were due to the new NICU being a single-family NICU or located in a newly constructed building warrants exploration. Long term health outcomes from the differences observed must be followed longitudinally.

Clinical, Social, and Genetic Factors Associated with Obesity at 12 Months of Age

OBJECTIVE

To examine genomic, social, and clinical risk factors of ≥85 weight for length percentile (WFLP) at 12 months.

STUDY DESIGN

Children in this study had whole-genome sequencing, and clinical and social data were collected. WFLPs at 12 months of age were grouped as follows: (1) <85th, (2) ≥85th to <95th, (3) ≥95th to <99th, and (4) ≥99th. Whole-genome sequencing data were used to analyze rare and common variants, and association of clinical and social factors was examined.

RESULTS

A total of 690 children were included; WFLPs were 422 (61.2%) <85th, 112 (16.2%) ≥85th-<95th, 89 (12.9%) ≥95th-<99th, and 67 (9.7%) ≥99th. Family-related risk factors associated with greater WFLP were greater paternal body mass index, WFLP ≥99th OR 1.10 (1.03-1.16), and greater than recommended weight gain in pregnancy, WFLP ≥85th-<95th OR 1.90 (1.09-3.26). More breast milk at 6 months was protective factor: WFLP ≥85th-<95th, OR 0.98 (0.97-0.99), WFLP ≥95th-<99th OR 0.98 (0.97-0.99), and WFLP ≥99th OR 0.98 (0.96-0.99). Although none of the variants reached genome-wide significance, there was a trend toward increased prevalence of genetic variants within or near genes previously associated with obesity in children with WFLP ≥99th.

CONCLUSION

This cross-sectional study identified several modifiable factors, including increased weight gain in pregnancy and decreased breast milk at 6 months, associated with greater WFLP at 12 months. Strong genetic factors were not identified.

Prenatal exposure to PM2.5 and birth weight: A pooled analysis from three North American longitudinal pregnancy cohort studies

A common practice when analyzing multi-site epidemiological data is to include a term for 'site' to account for unmeasured effects at each location. This practice should be carefully considered when site can have complex relationships with important demographic and exposure variables. We leverage data from three longitudinal North American pregnancy cohorts to demonstrate a novel method to assess study heterogeneity and potential combinability of studies for pooled analyses in order to better understand how to consider site in analyses. Results from linear regression and fixed effects meta-regression models run both prior to and following the proposed combinability analyses were compared. In order to exemplify this approach, we examined associations between prenatal exposure to particulate matter and birth weight. Analyses included mother-child dyads (N=1966) from the Asthma Coalition on Community Environment and Social Stress (ACCESS) Project and the PRogramming of Intergenerational Stress Mechanisms (PRISM) study in the northeastern United States, and the Programming Research in Obesity, Growth, Environment and Social Stressors (PROGRESS) study in Mexico City. Mothers' daily third trimester exposure to particulate matter≤2.5μm in diameter (PM_2.5) was estimated using a validated satellite-based spatio-temporally resolved model in all studies. Fenton birth weight for gestational age z-scores were calculated. Linear regression analyses within each cohort separately did not find significant associations between PM_2.5 averaged over the third trimester and Fenton z-scores. The initial meta-regression model also did not find significant associations between prenatal PM_2.5 and birthweight. Next, propensity scores and log linear models were used to assess higher order interactions and determine if sites were comparable with regard to sociodemographics and other covariates; these analyses demonstrated that PROGRESS and ACCESS were combinable. Adjusted linear regression models including a 2-level site variable according to the pooling indicated by the log linear models (ACCESS and PROGRESS as one level and PRISM as another) revealed that a 5μg/m³ increase in PM_2.5 was associated with a 0.075 decrease in Fenton z-score (p<0.0001); linear models including a 3-level site variable did not reveal significant associations. By assessing the combinability of heterogeneous populations prior to combining data using a method that more optimally accounts for underlying cohort differences, we were able to identify significant associations between prenatal PM_2.5 exposure and birthweight that were not detected using standard methods.

Utilization of genomic sequencing for population screening of immunodeficiencies in the newborn

PurposeImmunodeficiency screening has been added to many state-directed newborn screening programs. The current methodology is limited to screening for severe T-cell lymphopenia disorders. We evaluated the potential of genomic sequencing to augment current newborn screening for immunodeficiency, including identification of non-T cell disorders.MethodsWe analyzed whole-genome sequencing (WGS) and clinical data from a cohort of 1,349 newborn-parent trios by genotype-first and phenotype-first approaches. For the genotype-first approach, we analyzed predicted protein-impacting variants in 329 immunodeficiency-related genes in the WGS data. As a phenotype-first approach, electronic health records were used to identify children with clinical features suggestive of immunodeficiency. Genomes of these children and their parents were analyzed using a separate pipeline for identification of candidate pathogenic variants for rare Mendelian disorders.ResultsWGS provides adequate coverage for most known immunodeficiency-related genes. 13,476 distinct variants and 8,502 distinct predicted protein-impacting variants were identified in this cohort; five individuals carried potentially pathogenic variants requiring expert clinical correlation. One clinically asymptomatic individual was found genomically to have complement component 9 deficiency. Of the symptomatic children, one was molecularly identified as having an immunodeficiency condition and two were found to have other molecular diagnoses.ConclusionNeonatal genomic sequencing can potentially augment newborn screening for immunodeficiency.

Investigating the accuracy of parentally reported weights and lengths at 12 months of age as compared to measured weights and lengths in a longitudinal childhood genome study

BACKGROUND

Childhood obesity studies rely on parentally reported anthropometrics. However, the accuracy of such data has not been evaluated for 12-month-old children. Moreover, methods to improve the accuracy of reported data have not been assessed in prior studies.

METHODS

A total of 185 children enrolled in a northern Virginia childhood longitudinal cohort genomic study had parentally completed surveys at 12 months. Measured weights and lengths were recorded for the same children from their 12-month paediatrician visit. Weight for length percentiles were calculated using World Health Organization gender-specific growth charts. The agreement between reported and measured values was examined using Pearson's correlation, paired t-test and κ statistics. The interquartile outlier rule was used to detect and remove outliers.

RESULTS

Parentally reported weight was strongly associated with measured weight at 12 months (r=0.90). There was only a moderate correlation between parentally reported and measured lengths (r=0.52) and calculated weight for length percentiles (r=0.65). After removing outliers from parentally reported data, there was an increase in correlation between parentally reported and measured data for weight (r=0.93), length (r=0.69) and weight for length percentiles (r=0.76). Outliers removed compared to all children included were more likely to have maternal education less than a bachelor's degree (p=0.007).

CONCLUSIONS

After removal of outliers from reported data, there is a strong correlation between calculated reported and measured weight for length percentiles suggesting that this may be an effective method to increase accuracy when conducting large-scale obesity studies in young children where study costs benefit from using parentally reported data.

Abstract IA18: Large-scale familial whole genome sequencing to evaluate genetic risk

Whole genome sequencing (WGS) technology and analysis is quickly approaching the stage of development where it can become a medically recognized procedure for prognostics as well as diagnostics. Critical to the development of medical-grade whole genome sequencing is the ability to recognize and minimize technological and biological variation in WGS data. The Inova Translational Medicine Institute (ITMI) has completed a study that generated 1500 whole genome sequences in 15 months and recently launched a study that will generate 20,000 WGS over the next two years. The 1500 sequenced genomes were from individuals from 53 countries, representing four major ancestral groups and many minor sub-groups. ITMI used these data to generate a database of ancestral-specific variants. This database can be used to identify single nucleotide variants in patients with a specific ancestral background as ancestral-specific sequences instead of mutations. This ancestral information was applied to the 487 cancer genes identified in the Wellcome Trust Sanger Institute's Cancer Gene Census, in an attempt to identify germline mutations in these genes, in our cohort of 1500 participants. The result of this analysis identifies the incidence and type of germline mutations in various ethnic groups. The ethical question that remains is what to do with incidental finding of this type as medical whole genome sequencing becomes a common tool in the practice of medicine.

Citation Format: Joseph Vockley, Ramaswamy Iyer, Kathi Huddleston, John Niederhuber. Large-scale familial whole genome sequencing to evaluate genetic risk. [abstract]. In: Proceedings of the AACR Special Conference on Post-GWAS Horizons in Molecular Epidemiology: Digging Deeper into the Environment; 2012 Nov 11-14; Hollywood, FL. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2012;21(11 Suppl):Abstract nr IA18.

Neonatal Torulopsis glabrata fungemia

Torulopsis glabrata is a yeastlike fungus that has recently become recognized as an important opportunistic pathogen. Only four cases of T glabrata infection in neonates have been reported. We report two cases of fungemia caused by this organism in premature infants. Both patients were treated with amphotericin B and survived the fungemia, but one patient later died of bacterial sepsis. Both patients had been treated with surfactant, artificial ventilation, intravascular catheters (arterial and venous), broad spectrum antibiotics, and hyperalimentation, which appear to be risk factors for T glabrata fungemia. A review of the literature indicates that T glabrata is susceptible to amphotericin B and 5-fluorocytosine and is resistant to fluconazole. In addition, it is less susceptible to ketoconazole, clotrimazole, and itraconazole than is Candida albicans. We recommend that T glabrata infections be treated initially by reducing iatrogenic risk factors and beginning amphotericin B therapy. If necessary, 5-fluorocytosine should be added to the drug regimen.

A comparison of infusion devices at 1 ml/hr

Delivery of medications by some infusion devices is irregular. This study investigated instantaneous flow in several infusion devices set at a rate of 1 ml/hr. The following devices were tested: Infusion Pumps: IMED 956A, IVAC 570, IVION "Kids Pump." Syringe Pumps: Medfusion, Baxter, Baxter OR. Tests were performed using a Bio-Tek Infusion Device Analyzer (Model IDA-1). Instantaneous flow rate was defined as Q1/T1 where: Q=sample volume and T=time required to deliver sample volume. The infusion devices were received directly from their respective manufacturers and had not seen clinical service before testing. The units were fully charged and were tested while on AC power. The tests were conducted by the authors, using standard infusion sets and commercially prepared 5% dextrose and 0.45% sodium chloride solution. Each pump was tested for several hours and multiple trials were performed on each pump. The infusion pumps, IMED, IVION, and IVAC all demonstrated deviations from the desired flow rate. The IVAC pump had a greater fluctuation in flow from the set value of 1 ml/hr (p less than 0.02). Variances from mean +/- standard error for each device are shown in parenthesis. IMED 965A (0.005+/-0.014), IVION Kid's Pump (0.002+/-0.009), IVAC 570 (0.001+/-0.006). The Baxter syringe pump (0.002+/-0.009) also had a wide variance in flow. The Baxter OR (0.001+/-0.005) and the Medfusion (0.001+/-0.008) syringe pumps maintained the most consistent flow and showed less variance than the other devices tested.(ABSTRACT TRUNCATED AT 250 WORDS)

An additional case of Smith-Lemli-Opitz syndrome in a 46,XY infant with female external genitalia

Ambiguity of the external genitalia has been frequently documented in male patients classified as the Smith-Lemli-Opitz (SLO) syndrome. Four previous case reports suggest that in extreme cases of the SLO syndrome there may be complete lack of development of the male external genitalia even in the presence of a normal male 46,XY karyotype. We present an additional case of a phenotypically female infant with dysmorphic features compatible with SLO syndrome and a 46,XY chromosome complement.