Updated Strategies for Pulse Oximetry Screening for Critical Congenital Heart Disease

Seven years after its addition to the US Recommended Uniform Screening Panel, newborn screening for critical congenital heart disease (CCHD) using pulse oximetry became mandatory in the United States. Although CCHD newborn screening reduces morbidity and mortality, there remain important opportunities to improve. An expert panel convened for a 1-day meeting in September 2018, including subject matter experts and representatives from stakeholder organizations. Presentations on CCHD outcomes, variations in approach to screening, and data and quality improvement helped identify improvement opportunities. The expert panel concluded that sufficient evidence exists to recommend modifying the current American Academy of Pediatrics algorithm by (1) requiring an oxygen saturation of at least 95% in both (formerly either) the upper and lower extremities to pass and (2) requiring only 1 repeat screen instead of 2 for cases that neither pass nor fail initially. The panel underscored the importance of improving public health reporting by further specifying the targets of screening and criteria for reporting outcomes (false-negative and false-positive cases). The panel also highlighted the need to ensure sufficient public health funding for CCHD newborn screening and opportunities for education and global implementation. Newborn screening for CCHD using pulse oximetry has led to significant improvements in child health outcomes. However, further important work is required to understand and improve the effectiveness and efficiency of screening.

Metabolite-related dietary patterns and the development of islet autoimmunity

The role of diet in type 1 diabetes development is poorly understood. Metabolites, which reflect dietary response, may help elucidate this role. We explored metabolomics and lipidomics differences between 352 cases of islet autoimmunity (IA) and controls in the TEDDY (The Environmental Determinants of Diabetes in the Young) study. We created dietary patterns reflecting pre-IA metabolite differences between groups and examined their association with IA. Secondary outcomes included IA cases positive for multiple autoantibodies (mAb+). The association of 853 plasma metabolites with outcomes was tested at seroconversion to IA, just prior to seroconversion, and during infancy. Key compounds in enriched metabolite sets were used to create dietary patterns reflecting metabolite composition, which were then tested for association with outcomes in the nested case-control subset and the full TEDDY cohort. Unsaturated phosphatidylcholines, sphingomyelins, phosphatidylethanolamines, glucosylceramides, and phospholipid ethers in infancy were inversely associated with mAb+ risk, while dicarboxylic acids were associated with an increased risk. An infancy dietary pattern representing higher levels of unsaturated phosphatidylcholines and phospholipid ethers, and lower sphingomyelins was protective for mAb+ in the nested case-control study only. Characterization of this high-risk infant metabolomics profile may help shape the future of early diagnosis or prevention efforts.

Lessons Learned From Newborn Screening for Critical Congenital Heart Defects

Newborn screening for critical congenital heart defects (CCHD) was added to the US Recommended Uniform Screening Panel in 2011. Within 4 years, 46 states and the District of Columbia had adopted it into their newborn screening program, leading to CCHD screening being nearly universal in the United States. This rapid adoption occurred while there were still questions about the effectiveness of the recommended screening protocol and barriers to follow-up for infants with a positive screen. In response, the Centers for Disease Control and Prevention partnered with the American Academy of Pediatrics to convene an expert panel between January and September 2015 representing a broad array of primary care, neonatology, pediatric cardiology, nursing, midwifery, public health, and advocacy communities. The panel's goal was to review current practices in newborn screening for CCHD and to identify opportunities for improvement. In this article, we describe the experience of CCHD screening in the United States with regard to: (1) identifying the target lesions for CCHD screening; (2) optimizing the algorithm for screening; (3) determining state-level challenges to implementation and surveillance of CCHD; (4) educating all stakeholders; (5) performing screening using the proper equipment and in a cost-effective manner; and (6) implementing screening in special settings such as the NICU, out-of-hospital settings, and areas of high altitude.

State Legislation, Regulations, and Hospital Guidelines for Newborn Screening for Critical Congenital Heart Defects - United States, 2011-2014

Critical congenital heart defects (CCHD) occur in approximately two of every 1,000 live births. Newborn screening provides an opportunity for reducing infant morbidity and mortality. In September 2011, the U.S. Department of Health and Human Services (HHS) Secretary endorsed the recommendation that critical congenital heart defects be added to the Recommended Uniform Screening Panel (RUSP) for all newborns. In 2014, CDC collaborated with the American Academy of Pediatrics (AAP) Division of State Government Affairs and the Newborn Screening Technical Assistance and Evaluation Program (NewSTEPs) to assess states' actions for adopting newborn screening for CCHD. Forty-three states have taken action toward newborn screening for CCHD through legislation, regulations, or hospital guidelines. Among those 43, 32 (74%) are collecting or planning to collect CCHD screening data; however, the type of data collected by CCHD newborn screening programs varies by state. State mandates for newborn screening for CCHD will likely increase the number of newborns screened, allowing for the possibility of early identification and prevention of morbidity and mortality. Data collection at the state level is important for surveillance, monitoring of outcomes, and evaluation of state CCHD newborn screening programs.

An update on the use of health information technology in newborn screening

Newborn screening (NBS) has high-stakes health implications and requires rapid and effective communication between many people and organizations. Multiple NBS stakeholders worked together to create national guidance for reporting NBS results with HL7 (Health Level 7) messages that contain LOINC (Logical Observation Identifiers Names and Codes) and SNOMED-CT (Systematized Nomenclature of Medicine-Clinical Terms) codes, report quantitative test results, and use standardized computer-readable UCUM units of measure. This guidance (a LOINC panel and an example annotated HL7 message) enables standard HL7 v2.5.1 laboratory messages to carry the information required for reporting NBS results. Other efforts include HL7 implementation guides for reporting point-of-care (POC) NBS results as well as standardizing follow-up of patients diagnosed with conditions identified through NBS. If the guidance is used nationally, regional and national registries can aggregate results from state programs to facilitate research and quality assurance and help ensure continuity of operations following a disaster situation.

Evidence for a causal relationship between early exocrine pancreatic disease and cystic fibrosis-related diabetes: a Mendelian randomization study

Circulating immunoreactive trypsinogen (IRT), a biomarker of exocrine pancreatic disease in cystic fibrosis (CF), is elevated in most CF newborns. In those with severe CF transmembrane conductance regulator (CFTR) genotypes, IRT declines rapidly in the first years of life, reflecting progressive pancreatic damage. Consistent with this progression, a less elevated newborn IRT measure would reflect more severe pancreatic disease, including compromised islet compartments, and potentially increased risk of CF-related diabetes (CFRD). We show in two independent CF populations that a lower newborn IRT estimate is associated with higher CFRD risk among individuals with severe CFTR genotypes, and we provide evidence to support a causal relationship. Increased loge(IRT) at birth was associated with decreased CFRD risk in Canadian and Colorado samples (hazard ratio 0.30 [95% CI 0.15-0.61] and 0.39 [0.18-0.81], respectively). Using Mendelian randomization with the SLC26A9 rs7512462 genotype as an instrumental variable since it is known to be associated with IRT birth levels in the CF population, we provide evidence to support a causal contribution of exocrine pancreatic status on CFRD risk. Our findings suggest CFRD risk could be predicted in early life and that maintained ductal fluid flow in the exocrine pancreas could delay the onset of CFRD.

Trajectories of adherence to airway clearance therapy for patients with cystic fibrosis

OBJECTIVE

Although cross-sectional studies have demonstrated poor adherence to airway clearance therapy (ACT) for patients with cystic fibrosis (CF), no studies have identified longitudinal patterns of adherence. The objective was to characterize and identify predictors of ACT adherence trajectories for individuals with CF.

METHODS

Secondary data analyses were conducted for a randomized clinical trial examining differences in three ACTs. Participants (n = 153; M = 14.3 years, 55% male, 86% Caucasian, baseline FEV(1)% predicted: M = 86.7)/primary caregivers completed Daily Phone Diaries, an empirically supported adherence measure, every 4 months.

RESULTS

Group-based trajectory modeling revealed the best-fitting solution was a three-group model: low-adherence (14%), medium-adherence (49%), and high-adherence (37%) groups. ACT type was the only significant predictor of adherence trajectories.

DISCUSSION

Three trajectories of adherence to ACT for patients with CF were found. With the identification of trajectories, adherence interventions can be targeted for the subgroup at highest risk in order to prevent poor health outcomes.

Update on enteral nutrition support for cystic fibrosis

Cystic fibrosis (CF) is an inherited disease affecting the respiratory, gastrointestinal, hepatobiliary, and reproductive systems. Nutrition status in persons with CF is often compromised due to increased energy needs, frequent infections, pancreatic insufficiency, lung disease, or CF-related diabetes. Maintaining good nutrition status has been associated with better pulmonary function, reduced hospitalizations, and increased longevity. Nutrition support as oral supplementation (used in >37% of the CF population) or tube feeding (used in >13% of the CF population) is often required for children and adults with CF. The purpose of this update is to describe current consensus and evidence for enteral nutrition support guidelines, reported complications of enteral feeding in the CF population, evidence of expected outcomes, and to discuss related areas requiring further research. A case report is provided to illustrate potential outcomes of aggressive enteral support.

Technology assessment of multileaf collimation: a North American users survey

PURPOSE

The American Association of Physicists in Medicine (AAPM) initiated an Assessment of Technology Subcommittee (ATS) to help the radiotherapy community evaluate emerging technologies. The ATS decided to first address multileaf collimation (MLC) by means of a North American users survey. The survey attempted to address issues such as MLC utility, efficacy, cost-effectiveness, and customer satisfaction.

METHODS AND MATERIALS

The survey was designed with 38 questions, with cross-tabulation set up to decipher a particular clinic's perception of MLC. The surveys were coded according to MLC types, which were narrowed to four: Elekta, Siemens, Varian 52-leaf, and Varian 80-leaf. A 40% return rate was desired.

RESULTS

A 44% (108 of 250) return was achieved. On an MLC machine, 76.5% of photon patients are being treated with MLC. The main reasons for not using MLC were stair stepping, field size limitation, and physician objection. The most common sites in which MLC is being used are lung, pelvis, and prostate. The least used sites are head & neck and mantle fields. Of the facilities, 31% claimed an increase in number of patients being treated since MLC was installed, and 44% claimed an increase in the number of fields. Though the staffing for block cutting has decreased, therapist staffing has not. However, 91% of the facilities claimed a decreased workload for the therapists, despite the increase in daily treated patients and fields. Of the facilities that justified MLC purchase for more daily patients, 63% are actually treating more patients. Only 26% of the facilities that justified an MLC purchase for intensity-modulated radiotherapy (IMRT) are currently using it for that purpose. The satisfaction rating (1 = low to 5 = high) for department groups averaged 4.0. Therapists ranked MLC as 4.6.

CONCLUSIONS

Our survey shows that most users have successfully introduced MLC into the clinic as a block replacement. Most have found MLC to be cost-effective and efficient. The use of MLC for IMRT has progressed slower, but users anticipate escalated use.

Low plasma zinc concentrations in young infants with cystic fibrosis

OBJECTIVES

The purpose of this study was to examine the zinc status of young infants with cystic fibrosis before and after the initiation of pancreatic enzyme therapy.

STUDY DESIGN

Cross-sectional data were obtained for infants with cystic fibrosis identified by newborn screening. Plasma zinc concentrations were measured and analyzed according to enzyme use at the time of the blood draw. On a subgroup of infants, zinc concentrations were determined again after several weeks with enzyme therapy.

RESULTS

Mean (+/-SD) plasma zinc concentration for the infants studied before the initiation of enzyme therapy was 10.4 +/- 2.2 micromol/L (68.3 +/- 14.7 microgram/dL) (n = 48), which was significantly lower than the mean for those receiving enzymes for >/=2 weeks, 11.8 +/- 2. 3 micromol/L (77.1 +/- 14.9 microgram/dL) (n = 15) (P =.03). For the group not yet receiving enzymes, 29% of infants had zinc concentrations in the deficient range. Data were available before and after enzyme therapy for 30 infants and indicated a mean increase of 1.64 +/- 3.0 micromol/L (10.7 +/- 19.3 microgram/dL) (P =. 005).

CONCLUSIONS

These data suggest that many of the infants were zinc deficient at the time of diagnosis. We conclude that zinc should be included among the specific micronutrients given consideration in the management of cystic fibrosis, particularly in infants.

Predicting the duration of dependence on parenteral nutrition after neonatal intestinal resection

OBJECTIVE

To determine whether there are clinical or physical factors that could be used to predict the duration of dependence on parenteral nutrition (PN) in infants who have undergone resection of small intestine in the neonatal period.

STUDY DESIGN

Medical records of 44 patients who had small intestinal resection as neonates from 1985 to 1996 and who were dependent on PN for at least 3 months were reviewed. Statistical evaluation of patient variables and their impact on duration of dependence on PN were determined by using the Cox Proportional Hazard model.

RESULTS

Twenty-seven patients became independent of PN before the age of 36 months. Seven patients between 40 and 129 months of age are permanently dependent on PN. Outcome could not be determined in 10 patients, four of whom died of hepatic failure while still receiving PN and six of whom are still receiving PN but are younger than 36 months of age. Small bowel length after initial surgery and the percent of daily energy intake received by the enteral route at 12 weeks' adjusted age were significantly related to the duration of dependence on PN. Gestational age, presence of the ileocecal valve, and development of cholestasis were not significantly related. With the use of the Cox Proportional Hazards survival model, a formula was generated to allow estimation of the duration of dependence on PN.

CONCLUSIONS

The duration of dependence on PN can be predicted at an early age in neonatal short bowel syndrome by using two patient variables: the length of residual small bowel after initial surgery and the percent of daily energy intake tolerated through the enteral route.

Coordinated activation of corneal wound response genes in vivo as observed by in situ hybridization

We used subtractive screening of a cDNA library prepared from corneoscleral rims after cauterizing rat corneas. We identified 76 clones whose corresponding mRNA increased during the wound healing process in an in vivo model of injury which damages the corneal epithelium, stroma, and endothelium. Of these clones, 31 sequences encode known proteins. Another 45 clones are novel sequences based on comparison with the GenBank/EMBL databases. Changes in the level of expression of the novel genes, and a selected number of the known genes, were examined by in situ hybridization 22 and 72 hr after corneal injury. The majority produced a 'wound pattern' of expression such that the mRNAs were highly induced in all cell types adjacent to the wound site at 22 hr post injury. This signal decreased in intensity with distance from the wound site. In a subset of corneoslceral rims examined by in situ hybridization, the mRNAs for these genes were also highly induced in the limbal epithelium, where the progenitor corneal epithelial stem cells reside. By 72 hr, when acute tissue damage had been repaired, the induced mRNA was only faintly present in the thickened epithelium. Our results provide a useful framework for further studies defining the pathophysiological roles of the known and novel proteins encoded by the isolated cDNA clones.

Three-dimensional photon treatment planning in carcinoma of the larynx

The role of three-dimensional (3-D) treatment planning in the definitive treatment of carcinoma of the larynx with radiation was evaluated at four institutions as part of an NCI contract. A total of 30 different treatment approaches were devised for two patients with larynx cancer. CT scans were obtained for both patients and various treatment planning tools were employed to optimize beam arrangements and to evaluate the resulting dose distribution. The effect on dose distribution of a number of factors was also examined: 1) the use of dose calculation algorithms which correct for tissue inhomogeneities, 2) the variation of the CT numbers used for inhomogeneity corrections to simulate inaccuracies in the knowledge of the CT numbers, and 3) the modification of beam energy. A multitude of data was used in plan evaluation and a numerical score was given to each plan to estimate the tumor control probability and the normal tissue complication probability. We found 3-D treatment planning to be of potential value in optimizing treatment plans in larynx cancer. Improved target coverage was achieved when complete information describing 3-D geometry of the anatomy was utilized. In some cases, the treatment planning tools employed, such as the beam's eye view, helped devise novel beam arrangements which were useful alternatives to standard techniques. We found little effect of change in CT number on dose distributions. A comparison between dose distributions calculated with tissue inhomogeneity corrections to those calculated without this correction showed little difference. We did find some improvement in the dose to the primary tumor volume at lower beam energies, but with an increased larynx volume potentially receiving doses above tolerance.

The role of uncertainty analysis in treatment planning

The role of uncertainty analysis in 3-D treatment planning systems was addressed by four institutions which contracted with NCI to evaluate high energy photon external beam treatment planning. Treatment plans were developed at eight disease sites and the effects of uncertainties assessed in a number of experiments. Uncertainties which are patient-site specific included variations in the delineation of target volumes and normal tissues and the effects of positional uncertainties due to physiological motion and setup nonreproducibility. These were found to have a potentially major impact on the doses to the target volumes and to critical normal tissues which could result in significantly altered probabilities of tumor control and normal tissue complications. Other uncertainties, such as the conversion of CT data to electron densities, heterogeneities and dose calculation algorithms' weaknesses, are related to physical processes. The latter was noted to have the greatest potential contribution to uncertainty in some sites. A third category of uncertainty related to the treatment machine, the consequences of compensator misregistration, are exclusive to the site and the treatment portal. Because conventional treatment planning systems have not incorporated uncertainty analysis, tools and techniques had to be devised for this work; further development in this area is needed. Many of the analyses could not have been done without full 3-D capabilities of the planning systems, and it can be anticipated that the availability of uncertainty analysis in these systems which allow nontraditional beam arrangements will be of great value.

Irradiation for xenogeneic transplantation

Xenogeneic transplantation (XT) is the transplantation of organs or tissues from a member of one species to a member of another. Mammalian species frequently have circulating antibody which is directed against the foreign organ irrespective of known prior antigen exposure. This antibody may lead to hyperacute rejection. There is no reliable means to avert hyperacute rejection once it ensues so efforts must be directed towards eliminating the pre-existing antibody. In those species in which hyperacute rejection of xenografts does not occur, cell-mediated rejection, similar to allograft rejection, may occur. It is in the prevention of this latter form of rejection that radiation is most likely to be beneficial in XT. Both total lymphoid irradiation (TLI) and selective lymphoid irradiation (SLI) have been investigated for use in conjunction with XT. TLI has contributed to the prolongation of pancreatic islet-cell xenografts from hamsters to rats. TLI has also markedly prolonged the survival of cardiac transplants from hamsters to rats. A more modest prolongation of graft survival has been seen with the use of TLI in rabbit-to-rat exchanges. Therapy with TLI, cyclosporine, and splenectomy has markedly prolonged the survival of liver transplants from hamsters to rats, and preliminary data suggest that TLI may contribute to the prolongation of graft survival in the transplantation of hearts from monkeys to baboons. SLI appears to have prolonged graft survival, when used in conjunction with anti-lymphocyte globulin, in hamster-to-rat cardiac graft exchanges. The current state of knowledge of the use of irradiation in experimental XT is reviewed.