Newborn screening fact sheets

Estimating prevalence of classical homocystinuria in the United States using Optum's de-identified market clarity data

Background and objectives

Prevalence estimates for classical homocystinuria (HCU) are variable and likely underestimated due to underdiagnosis. Claims data represent a strong but seldom used resource to analyze prevalence of HCU. The aim of this study was to estimate a prevalence range of HCU in the US utilizing a combination of diagnosis codes, total homocysteine levels, and clinical presentations indicative of HCU.

Methods

This was a non-interventional retrospective cohort study, using Optum's de-identified Market Clarity Data, with a patient identification period from January 01, 2016, through September 30, 2021. An algorithm was developed to identify 2 cohorts of patients using broad and strict definitions of HCU. The index date was the date within the identification period on which the first criterion was met for the inclusion criteria. Baseline demographics, clinical characteristics, and complications were assessed and summarized using descriptive statistics. Crude and standardized prevalence estimates were calculated.

Results

There were 3880 and 633 patients that met the relevant inclusion criteria for the broad and strict cohorts, respectively. The projected US prevalence of HCU was calculated to be 17,631 and 3466 based on the broad and strict definitions, respectively. The average annual standardized prevalence across 2016-2020 was 5.29 and 1.04 per 100,000 people for the broad and strict cohorts, respectively.

Conclusions

Prevalence estimates of HCU vary depending on databases or datasets used and identification criteria. Many patients with clinical presentations suggesting a diagnosis of HCU did not have an associated diagnosis, potentially indicating underdiagnosis or underreporting. Future research should study alternative methods, such as the identification algorithm in our analysis, to better diagnose and understand the true prevalence of HCU.

Predictive value of fluorometric method and tandem mass spectrometry for hyperphenylalaninemia and its subtypes in China: A systematic review and meta‑analysis

The present study aimed to conduct a comprehensive meta-analysis to assess the diagnostic value of fluorometric assays and tandem mass spectrometry (MS/MS) for hyperphenylalaninemia (HPA) and its subtypes. The PubMed, Embase and Cochrane Library databases were searched from inception to October 2023. The present study included studies that reported the newborn screening and genetic features of patients with HPA and excluded duplicate publications, studies without full text, studies with incomplete information, studies from which it was not possible to extract data, animal experiments, reviews and systematic reviews. STATA 15.1 was used to analyze the data. The pooled results revealed that 0.04% [95% confidence interval (CI): 0.019-0.069] of neonatal HPA fluorometric assays and MS/MS. The positive predictive value (PPV) of neonatal HPA screening using fluorometric assays and tandem mass spectrometry was 31.7% (95% CI: 19.6-45.2). Notably, the PPV of neonatal HPA screening using fluorometric assays was 8.3% (95% CI: 7.1-9.6), while the PPV of neonatal HPA screening using tandem mass spectrometry was 31.8% (95% CI: 16.4-49.4). Additionally, the pooled results showed that the incidence of tetrahydrobiopterin deficiency (BH4D) in HPA patients was 12.43% (95% CI: 3.28-25.75) and the incidence of phenylalanine hydroxylase deficiency (PAHD) in HPA patients was 88.65% (95% CI: 78.84-95.86). Newborn screening is an effective method for the early detection of HPA and MS/MS has a greater PPA than fluorometric assays for diagnosing HPA. In addition, in the screening of HPA, the proportion of HPA patients with PAHD was significantly higher than that of patients with BH4D.

Whole-body galactose oxidation as a robust functional assay to assess the efficacy of gene-based therapies in a mouse model of Galactosemia

Despite the implementation of lifesaving newborn screening programs and a galactose-restricted diet, many patients with classic galactosemia develop long-term debilitating neurological deficits and primary ovarian insufficiency. Previously, we showed that the administration of human GALT mRNA predominantly expressed in the GalT gene-trapped mouse liver augmented the expression of hepatic GALT activity, which decreased not only galactose-1 phosphate (gal-1P) in the liver but also peripheral tissues. Since each peripheral tissue requires distinct methods to examine the biomarker and/or GALT effect, this highlights the necessity for alternative strategies to evaluate the overall impact of therapies. In this study, we established that whole-body galactose oxidation (WBGO) as a robust, noninvasive, and specific method to assess the in vivo pharmacokinetic and pharmacodynamic parameters of two experimental gene-based therapies that aimed to restore GALT activity in a mouse model of galactosemia. Although our results illustrated the long-lasting efficacy of AAVrh10-mediated GALT gene transfer, we found that GALT mRNA therapy that targets the liver predominantly is sufficient to sustain WBGO. The latter could have important implications in the design of novel targeted therapy to ensure optimal efficacy and safety.

Attitudes and beliefs regarding race-targeted genetic testing of Black people: A systematic review

Geographical ancestry has been associated with an increased risk of various genetic conditions. Race and ethnicity often have been used as proxies for geographical ancestry. Despite numerous problems associated with the crude reliance on race and ethnicity as proxies for geographical ancestry, some genetic testing in the clinical, research, and employment settings has been and continues to be race- or ethnicity-based. Race-based or race-targeted genetic testing refers to genetic testing offered only or primarily to people of particular racial or ethnic groups because of presumed differences among groups. One current example is APOL1 testing of Black kidney donors. Race-based genetic testing raises numerous ethical and policy questions. Given the ongoing reliance on the Black race in genetic testing, it is important to understand the views of people who identify as Black or are identified as Black (including African American, Afro-Caribbean, and Hispanic Black) regarding race-based genetic testing that targets Black people because of their race. We conducted a systematic review of studies and reports of stakeholder-engaged projects that examined how people who identify as or are identified as Black perceive genetic testing that specifically presumes genetic differences exist among racial groups or uses race as a surrogate for ancestral genetic variation and targets Black people. Our review identified 14 studies that explicitly studied this question and another 13 that implicitly or tacitly studied this matter. We found four main factors that contribute to a positive attitude toward race-targeted genetic testing (facilitators) and eight main factors that are associated with concerns regarding race-targeted genetic testing (barriers). This review fills an important gap. These findings should inform future genetic research and the policies and practices developed in clinical, research, public health, or other settings regarding genetic testing.

Breastfeeding in Phenylketonuria: Changing Modalities, Changing Perspectives

Phenylketonuria (PKU) management aims to control phenylalanine (Phe) intakes. In newborns and infants this implies possible titration of Human milk (HM) with supplementation of Phe-free formula. HM benefits, better if prolonged, are well known in healthy populations, suggesting it may be used in PKU patients. Despite that, the current literature does not define recommendations on how best perform it in such a population. The main purpose of this study was to evaluate nutrition approaches in newborns and infants affected by PKU and to define if differences can influence the duration of breastfeeding. Data from 42 PKU infants were reviewed. Of these, 67% were breastfed with the use of three different approaches. The type of approach used impacted the duration of breastfeeding, which was longer when using a pre-measured amount of Phe-free formula administered prior to HM. This is the first study to suggest a specific method for breastfeeding in PKU. Considering widely known breastfeeding benefits, both for patients and their mothers, our data should encourage adequate awareness on how to choose correct breastfeeding modalities.

Newborn screening and genetic features of patients with hyperphenylalaninemia in a southern Chinese population

BACKGROUND AND AIMS

Hyperphenylalaninemia (HPA) is the most common congenital amino acid metabolism-related defect, but its incidence differs substantially between northern and southern China. We aimed to elucidate the incidence, proportion, and genetic features of HPA in a southern Chinese population.

MATERIALS AND METHODS

We analyzed the HPA screening results for 580,460 newborns from 2014 to 2021.

RESULTS

Of the 296 newborns who tested HPA positive, 56 were diagnosed with HPA, including 47 with phenylalanine hydroxylase deficiency and nine with tetrahydrobiopterin deficiency (BH4D). HPA incidence was estimated to be 1:10,365 newborns. All patients had elevated Phe and Phe/Tyr levels. Thirty-three PAH variants and five PTS variants were detected in HPA patients; 80.6 % PAH variants and 100 % PTS variants were classified as pathogenic or likely pathogenic. In silico tools predicted the remaining variants to be damaging. PAH variants clustered in exons 3, 5, 7, 11, and 12 and PTS variants clustered in exons 2 and 5. The most common PAH variants were c.158G > A (p.R53H, 22.3 %) and c.721C > T (p.R241C, 14.9 %). The most common PTS variants were c.155A > G (p.N52S, 50.0 %) and c.259C > T (p.P87S, 33.3 %).

CONCLUSION

Newborn screening is an effective method for early detection of HPA, but differential diagnosis of BH4D is necessary.

Quantitative analysis of galactose using LDI-TOF MS based on a TiO2 nanowire chip

A novel method for quantifying galactose was developed to serve as a newborn screening test for galactosemia using laser desorption/ionization time-of-flight (LDI-TOF) mass spectrometry (MS) with a TiO2 nanowire chip. Herein, phosphate citrate buffer, serum, and dried blood spot (DBS) were employed for the quantitative analysis of galactose. To quantitatively analyze galactose, its reduction potential was used to oxidize o-phenylene diamine (OPD) into 2,3-diaminophenazine (DA), which were both detected using LDI-TOF MS with a TiO2 nanowire chip according to the concentration of galactose. The reproducibility and the interference of glucose were determined to demonstrate the applicability of this method. Moreover, mixtures of galactose, phenylalanine, and 17 α-OHP were analyzed to determine the interference induced by other biomarkers of metabolic disorders. The OPD oxidation of galactose was found to be selectively achieved under high-glucose conditions, similar to human blood, thereby showing good reproducibility. The intensities of the mass peaks of OPD and DA based on LDI-TOF MS with a TiO2 nanowire chip were linearly correlated in the galactose concentration range of 57.2–220.0 μg/mL (r2 = 0.999 and 0.950, respectively) for serum samples and 52.5–220.0 μg/mL (r2 = 0.993 and 0.985, respectively) for DBS after methanol precipitation/extraction. The enzyme immunoassay and LDI-TOF MS analysis results were statistically analyzed, and a mixture of phenylalanine, 17 α-OHP, and galactose was simultaneously investigated quantitatively at the cutoff level.

The progression of salt-wasting and the body weight change during the first 2 weeks of life in classical 21-hydroxylase deficiency patients

BACKGROUND

One of the major purposes of newborn screening for 21-hydroxylase deficiency (21OHD) is preventing life-threatening adrenal crisis. However, the details of adrenal crisis in newborns are not precisely documented.

AIM

We aimed to clarify the clinical details of salt-wasting in newborn 21OHD patients.

METHODS

Based on the follow-up survey of the screening in Tokyo from 1989 to 2017, we retrospectively analysed the conditions of classical 21OHD neonates before the initiation of therapy.

RESULTS

One hundred classical 21OHD patients (55 male, 45 female) were analysed. The age at the first hospital visit was 0-20 days with sex difference (male: 9.0 ± 3.5 days; female: 6.2 ± 3.9 days). Thirty-seven (37.4%) patients exhibited severe salt-wasting (SSW), that is, Na < 130 mEq/L, K > 7 mEq/L or Na/K ratio < 20; except for one case, SSW developed in or after the second week of life. The serum concentrations of Na, K and Na/K were linearly correlated with age in days (R²  = .38, .25, and .34 respectively), suggesting that the risk of SSW increases linearly without a threshold. The age at which the regression lines reached Na < 130 mEq/L, K > 7 mEq/L and Na/K < 20 was approximately coincided, 11.1, 12.3 and 11.2 days, respectively. All SSW patients exhibited decreased body weight from birth in their second week of life.

CONCLUSION

Our data revealed that the risk of developing SSW increases during the second week of life without a threshold, and for preventing SSW, early intervention, ideally during first week of life, is desirable. An increased body weight in the second week of life indicates the absence of SSW.

Challenges in Assessing the Cost-Effectiveness of Newborn Screening: The Example of Congenital Adrenal Hyperplasia

Generalizing about the cost-effectiveness of newborn screening (NBS) is difficult due to the heterogeneity of disorders included in NBS panels, along with data limitations. Furthermore, it is unclear to what extent evidence about cost-effectiveness should influence decisions to screen for specific disorders. Screening newborns for congenital adrenal hyperplasia (CAH) due to 21-hydroxylase deficiency can serve as a useful test case, since there is no global consensus on whether CAH should be part of NBS panels. Published and unpublished cost-effectiveness analyses of CAH screening have yielded mixed findings, largely due to differences in methods and data sources for estimating health outcomes and associated costs of early versus late diagnosis as well as between-country differences. Understanding these methodological challenges can help inform future analyses and could also help interested policymakers interpret the results of economic evaluations.

Adrenocortical hyperplasia: a review of clinical presentation and imaging

Adrenal hyperplasia is non-malignant enlargement of the adrenal glands, which is often bilateral. It can be incidental or related to indolent disease process and may be related to benign or malignant etiologies causing biochemical alterations in the hypothalamic-pituitary-adrenal axis which controls steroidogenesis and in particular cortisol production. Clinical significance of the adrenal hyperplasia is variable ranging from asymptomatic finding to serious manifestations of Cushing syndrome. This is often associated with anatomical changes in the adrenal glands, which typically manifests as diffuse and sometimes nodular enlargement of the adrenal glands radiologically. Approaching adrenal hyperplasia requires careful clinical and biochemical evaluation in correlation with imaging review to differentiate ACTH-dependent and ACTH-independent etiologies. CT is the primary modality of choice for adult adrenal imaging owing to reproducibility, temporal and spatial resolution and broader access, while MRI often serves a complimentary role. Ultrasound and MRI are most commonly used in pediatric cases to evaluate congenital adrenal hyperplasia. This article will discuss the clinical presentation and imaging features of different types and mimics of adrenal cortical hyperplasia.

Novel mRNA-Based Therapy Reduces Toxic Galactose Metabolites and Overcomes Galactose Sensitivity in a Mouse Model of Classic Galactosemia

Classic galactosemia (CG) is a potentially lethal inborn error of galactose metabolism that results from deleterious mutations in the human galactose-1 phosphate uridylyltransferase (GALT) gene. Previously, we constructed a GalT^-/- (GalT-deficient) mouse model that exhibits galactose sensitivity in the newborn mutant pups, reduced fertility in adult females, impaired motor functions, and growth restriction in both sexes. In this study, we tested whether restoration of hepatic GALT activity alone could decrease galactose-1 phosphate (gal-1P) and plasma galactose in the mouse model. The administration of different doses of mouse GalT (mGalT) mRNA resulted in a dose-dependent increase in mGalT protein expression and enzyme activity in the liver of GalT-deficient mice. Single intravenous (i.v.) dose of human GALT (hGALT) mRNA decreased gal-1P in mutant mouse liver and red blood cells (RBCs) within 24 h with low levels maintained for over a week. Repeated i.v. injections increased hepatic GalT expression, nearly normalized gal-1P levels in liver, and decreased gal-1P levels in RBCs and peripheral tissues throughout all doses. Moreover, repeated dosing reduced plasma galactose by 60% or more throughout all four doses. Additionally, a single intraperitoneal dose of hGALT mRNA overcame the galactose sensitivity and promoted the growth in a GalT^-/- newborn pup.

Screening and mutation analysis of hyperphenylalaninemia in newborns from Xiamen, China

In this study, we evaluated the incidence and genetic characteristics of hyperphenylalaninemia (HPA) in Xiamen, China. We analyzed the newborn screening data of HPA, obtained using a fluorometric method and tandem mass spectrometry (MS/MS), from 2013 to 2017. The suspected positive samples were further diagnosed using MassArray technology, multiplex ligation-dependent probe amplification (MLPA), and Sanger sequencing. A total of 418,831 newborns were screened, of whom 19 were diagnosed as HPA patients, with an incidence of 1:22,044. Of these HPA patients, 15 tested positive for phenylketonuria (PKU, 1:27922), and 4 tested positive for tetrahydrobiopterin deficiency (BH4D, 1:104,708). A total of 17 mutations were identified among 38 alleles in the 19 patients, with a detection rate of 94.74%, including 13 PAH and 4 PTS mutations. Among these, the c.721C>T, c.728G>A, c.1197A>T, c.611A>G and c.331C>T mutations, and the c.259C>T and c.155A>G mutations were the most prevalent PAH and PTS mutations in Xiamen, respectively. Therefore, this study systematically demonstrated the incidence and mutation spectrum of HPA in Xiamen. This information would contribute to genetic counseling, prenatal diagnosis, and management of HPA patients. Moreover, combining MS/MS technology with molecular genetic diagnosis is an effective strategy for future newborn HPA screening in Xiamen.

Risk factors for hearing loss in children: a systematic literature review and meta-analysis protocol

BACKGROUND

Hearing loss in newborns and children is a public health concern, due to high prevalence and negative effects on their development. Early detection and intervention of childhood hearing loss may mitigate these negative effects. Population-based newborn hearing screening programs have been established worldwide to identify children at risk for congenital hearing loss and to follow children at risk for late onset or progressive hearing loss. This article presents the protocol for a systematic review that aims to review the risk factors associated with permanent hearing loss in children, including congenital, early, or late onset. Risk factors associated with progressive hearing loss will be investigated as a secondary aim.

METHODS

Scientific literature from the following databases will be investigated: MEDLINE, Ovid MEDLINE(R) Daily and Ovid MEDLINE(R), Embase, and CINAHL. The primary outcome is a permanent bilateral or unilateral hearing loss with congenital onset or onset during childhood (birth to 18 years). The secondary outcome is progressive hearing loss. Studies must report data on risk factors associated with permanent hearing loss; risk factors may be present at birth or later and result in immediate or delayed hearing loss. Randomized controlled trials, quasi-experimental studies, nonrandomized comparative and non-comparative studies, and case series will be included. The risk of bias will be assessed using the Qualitative Assessment Tool for Quantitative Studies (McMaster University). If aggregation of data is possible for a subsection of studies, we will pool data using meta-analysis techniques. If aggregation of data is not possible, a qualitative synthesis will be presented. We will assess the quality and strength of the overall body of evidence using the Grading of Recommendations Assessment, Development and Evaluation (GRADE). The systematic review follows the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) recommendations.

DISCUSSION

The resulting information will inform the update of a provincial audiological surveillance protocol for the Ontario Infant Hearing Program and will be applicable to early hearing detection and intervention (EHDI) programs worldwide.

SYSTEMATIC REVIEW REGISTRATION

We have registered the protocol in the International Prospective Register of Systematic Reviews (PROSPERO), registration number CRD42018104121.

Rapid method towards proteomic analysis of dried blood spots by MALDI mass spectrometry

Neonatal dried blood spots (DBS) are routinely utilized in the clinical setting as a diagnostic tool for various genetic disorders and infectious diseases. DBS allow for minimally invasive, small volume blood collection and are stored at room temperature. Neonatal whole blood and serum samples can be important in determining genetic risk factors and predicting infantile disease; however, at the present time, limited methods exist for rapidly analyzing DBS samples for their proteomic profile, years after samples have been collected. A novel method is presented for the extraction and analysis of target proteins and peptides from neonatal DBS using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). Extraction parameters were optimized to achieve ideal signal intensity and resolution to obtain protein identifications. Samples were extracted from filter paper with 0.1% TFA in H₂O for 72 h. The extract was subjected to enzymatic digestion, spotted on an ITO-coated glass slide, and washed in order to remove salts. Analysis of extracted blood spots from ten newborns was completed. Similarities and differences in the proteomic profile of the washed extracts are presented, herein, to verify the viability of this method for analysis of dated DBS samples. This method allows for analysis of DBS samples years after collection and can be utilized to correlate diseases or disorders manifesting later in life with potential risk factors presenting in the proteomic profile of the DBS collected at time of birth.

Betaine anhydrous in homocystinuria: results from the RoCH registry

Background

The Registry of Adult and Paediatric Patients Treated with Cystadane® – Homocystinuria (RoCH) is a non-interventional, observational, multi-centre, post-authorization safety study that aimed to identify safety of betaine anhydrous (Cystadane®) in the treatment of patients with inborn errors of homocysteine metabolism (homocystinuria) in order to minimise the treatment associated risks and establish better knowledge on its clinical use. The registry included patients of all ages with homocystinuria who were treated with betaine anhydrous in conjunction with other therapies. Clinical data were collected retrospectively from 2007 to 2013, then prospectively up to February 2014. All adverse events (AEs) reported during the study were recorded. The clinical and biological status of patients was monitored at least once a year.

Results

A total of 125 patients with homocystinuria (adults [> 18 years]: 50; paediatric [≤18 years]: 75) were enrolled at 29 centres in France and Spain. Patients were treated with betaine anhydrous for a mean duration of 7.4 ± 4.3 years. The median total daily dose of betaine anhydrous at the first and last study visits was 6 g/day for cystathionine β-synthase (CBS)-deficient vitamin B6 responders and 9 g/day for methylenetetrahydrofolate reductase-deficient patients, while the median daily dose increased in CBS-deficient B6 non-responders (from 6 to 9 g/day) and cobalamin metabolism-defective patients (from 3 to 6 g/day) between the first and last visits. Treatment caused a mean overall reduction of 29% in plasma homocysteine levels in the study population. A total of 277 AEs were reported during the study, of which two non-serious AEs (bad taste and headache) and one serious AE (interstitial lung disease) were considered to be drug related. Overall, betaine anhydrous was well tolerated with no major safety concerns.

Conclusions

Data from the RoCH registry provided real-world evidence on the clinical safety and efficacy of betaine anhydrous in the management of homocystinuria in paediatric and adult patients.

Electronic supplementary material

The online version of this article (10.1186/s13023-019-1036-2) contains supplementary material, which is available to authorized users.

National Survey Assessment of the United States' Pediatric Residents' Knowledge, Attitudes, and Practices Regarding Newborn Screening

A pediatrician's approach to newborn screening (NBS) impacts patient care. Some physicians have reported not being well prepared to inform families about a positive NBS and recommend further follow-up. The knowledge and approach of categorical pediatric residents (RES) in the United States regarding NBS is not known. They were anonymously surveyed via listserv maintained by American Academy of Pediatrics. A total of 655 responses were analyzed. The mean composite knowledge score (CKS) was 17.7 (SD 1.8), out of maximum 21. Training level (p = 0.001) and completing NICU rotation (p < 0.001) predicted higher CKS. Most RES agreed that NBS is useful and pediatricians play an important role in the NBS process, however, only 62% were comfortable with counseling. Higher level RES were more likely to follow NBS results in clinic (p = 0.0027) and know the contact agency for results (p < 0.001). Most RES wanted more NBS training during residency and were not aware of clinical algorithms like ACTion sheets developed by American College of Medical Genetics. We concluded that although RES have sufficient knowledge about NBS, there is a need for earlier RES education on available tools for NBS to enhance their comfort level and improve practices such as educating parents about the NBS process.

Gestational age, not transient hyperthyrotropinemia impacts brain white matter diffusion tensor imaging in premature infants

Transient hypothyroidism is common in premature infants and increases the risk of adverse neurodevelopmental outcomes. Thyroid hormone (TH) is involved in oligodendrocyte development and myelination, however, whether transient hypothyroidism is associated with oligodendrocyte dysplasia and abnormal myelination is unclear. The aim of the present study was to investigate correlations among TH levels, neurodevelopmental outcomes and white matter (WM) microstructure in premature infants. The authors designed a cohort study recruiting 81 premature infants (age, 23-35 weeks). A total of 17 were born with a gestational age (GA) <30 weeks (early preterm group) and 64 of them were born with a GA ≥30 weeks (late preterm group). For outcome measurement, thyroid stimulating hormone (TSH) levels at 0, 18, and 24 h of admission were measured. Neurodevelopmental outcomes were assessed using Bayley III test. Diffusion tensor imaging was used to explore the characterization of WM microstructure. The data demonstrated that GA, however not TSH level was associated with neurodevelopmental outcomes in the following 2 years. Fractional anisotrophy (FA) increased with TSH0 levels over anterior limb of internal capsule, while axial diffusivity decreased with TSH0 levels over splenium of corpus callosum (CC). The late preterm group had more intact WM integrity over the internal and external capsule (EC) in FA compared with the early preterm group. Infants with motor dysfunction had significantly increased mean diffusivity (MD) values at regions of interest in the genu and splenium of CC. The results of the present study demonstrated that GA, however not transient hypothyroidism influenced neurodevelopmental outcomes in the premature infants. FA increased with age in a regionally-specific manner over regions of the internal capsule and EC. MD may act as a potential predictor for motor function in premature babies.

Improving early audiological intervention via newborn hearing screening in Belgium

BACKGROUND

Newborn hearing screening programs aim to lower the ages at audiological intervention among hearing-impaired children. In Wallonia and Brussels (Belgium), audiological intervention data are not collected in the screening program, and the ages at initiating audiological care have never been assessed. This study aimed to assess the evolution in the ages at initiating audiological intervention in the context of a newborn hearing screening program implementation.

METHODS

This population-based descriptive study used data from the Belgian healthcare billing database. The main outcomes were the children's ages at the initial audiological assessment, hearing-aid fitting, and cochlear implantation. Results were compared to the same outcomes from another Belgian regional program (Flanders) that was implemented one decade earlier. Annual birth cohorts from 2006 to 2011 were included in the study.

RESULTS

In Wallonia-Brussels, the median ages for all outcomes tended to decrease over time but remained higher than in Flanders for each birth cohort. For all outcomes except the hearing-aid fitting, differences in median ages between the two regions became less pronounced during the study period. In 2006, < 23% of the children from Wallonia-Brussels received any audiological care before the age of 12 months and these proportions were approximately 2-fold greater in the subsequent birth cohorts. For all outcomes, early care (< 12 months) was typically delivered less frequently in Wallonia-Brussels, compared to the delivery in Flanders. These region-specific differences exhibited a decreasing trend over time, and statistically significant differences were less common in the later birth cohorts.

CONCLUSIONS

We conclude that the hearing screening program in Wallonia and Brussels promoted earlier audiological intervention among hearing-impaired children. However, milestones recommended by experts for an early intervention were not totally encountered. We also recommend collecting audiological intervention data as part of this program, which can facilitate more accurate and regular program evaluation.

Attitudes toward clinical trials among patients with sickle cell disease

Background A substantial number of planned clinical trials for sickle cell disease (SCD) have terminated early due to insufficient patient enrollment. Purpose To describe attitudes toward clinical trials among a sample of adults with SCD and identify patient-level factors associated with these attitudes. Methods Our data came from a sample (N = 291) of primarily adults with SCD participating in the Improving Patient Outcomes with Respect and Trust (IMPORT) study, which is a federally funded observational study of SCD patient experiences in seeking healthcare. Attitudes toward clinical trials were assessed using items from the Perceptions of Participation in Clinical Research instrument. Patient factors examined as potential correlates of clinical trial attitudes were demographics, disease severity, engagement in self-care, trust, healthcare experience ratings, and prior history of participation in clinical trials. Multiple regression analyses were used to identify patient-level correlates of clinical trial attitudes. Results Our sample of SCD patients expressed overwhelmingly favorable attitudes about clinical trials, with 77%-92% of our sample expressing agreement with a series of positive statements about clinical trials in general. Demographics, engagement in self-care, healthcare experience ratings, and prior trial participation each explained significant portions of the variability in clinical trial attitudes. Limitations The generalizability of our results to the entire SCD population may be of concern as the study participants were all receiving care at comprehensive sickle cell centers and already participating in clinical research. Conclusion Our results suggest that, in principle, adults with SCD enrolled in an observational study express very positive general attitudes about clinical trial participation and that specific factors attached to particular clinical trial opportunities may play a greater role in a SCD patient's decision to participate than a general unwillingness to participate.

The Cystic Fibrosis Foundation Patient Registry. Design and Methods of a National Observational Disease Registry

RATIONALE

The Cystic Fibrosis Foundation Patient Registry (CFFPR) is an ongoing patient registry study that collects longitudinal demographic, clinical, and treatment information about persons with cystic fibrosis (CF) in the United States. CF is a life-shortening genetic disorder that occurs in approximately 1 in 3,500 births in the United States. High-quality observational data is important for clinical research, quality improvement, and clinical management.

OBJECTIVES

To describe the data collection, patient population, and key limitations of the CFFPR.

METHODS

Inclusion criteria for the CFFPR include diagnosis with CF or a CFTR-associated disorder, care at an accredited care center program, and provision of informed consent. Data from clinic visits and hospitalizations are collected through a secure website. Loss to follow-up and generalizability were examined using several methods. The accuracy of CFFPR data was evaluated with an audit of 2012 CFFPR data compared to the medical record.

MEASUREMENTS AND MAIN RESULTS

Since 1986, the CFFPR contains the records of 48,463 individuals with CF. Participation among individuals seen at accredited care centers is high, and loss to follow-up is low. An audit of 2012 CFFPR data suggests that the CFFPR contains 95% of clinic visits and 90% of hospitalizations found in the medical record for these patients, and nearly all of the audited fields were highly accurate.

CONCLUSIONS

Registries such as the CFFPR are important tools for research, clinical care, and tracking incidence, mortality and population trends.

Incidence of Neonatal Hyperphenylalaninemia Based on High-performance Liquid Chromatography Confirmatory Technique in Mazandaran Province, Northern Iran (2007-2015)

Background:

Classic phenylketonuria (PKU) is a metabolic disorder. The purpose of this study was to assess epidemiological factors of PKU phenotypes in a neonatal screening program for Mazandaran, Iran.

Methods:

In this descriptive-retrospective study from 2007 to 2015, neonates PKU level was conducted by phenylalanine level based on a biochemical technique by ELISA and then by confirmatory methods high performance liquid chromatography.

Results:

Of the 407,244 screened newborns (48.7% girls and 51.3% boys), 14 girls and 13 boys were diagnosed definitely from 465 suspicious cases of PKU. The incidence of PKU was 0.66 in 10,000, which was noted in different severity (severe PKU - 1:67,874, mild PKU - 1:45,249, and HPA - 1:33,937). In addition, we did not detect any cases of nonclassic PKU.

Conclusions:

Although the consanguineous marriage pattern is a major cause of hyperphenylalaninemia (HPA) particularly in Iranian, there was no significant difference between groups in this study. Now, screening should be executed for all of the family that they have the familial history of PKU in Iran. According to varies actual of prevalence and incidence rate of PKU reported a real patient and taking PKU with mild PKU and HPA, it is recommended, the will provide the PKU reports based on the severity of the disease.

Laboratory diagnosis of galactosemia: a technical standard and guideline of the American College of Medical Genetics and Genomics (ACMG)

Disclaimer: These ACMG Standards and Guidelines are developed primarily as an educational resource for clinical laboratory geneticists to help them provide quality clinical laboratory genetic services. Adherence to these Standards and Guidelines is voluntary and does not necessarily assure a successful medical outcome. These Standards and Guidelines should not be considered inclusive of all proper procedures and tests or exclusive of other procedures and tests that are reasonably directed to obtaining the same results. In determining the propriety of any specific procedure or test, the clinical laboratory geneticist should apply his or her own professional judgment to the specific circumstances presented by the individual patient or specimen. Clinical laboratory geneticists are encouraged to document in the patient's record the rationale for the use of a particular procedure or test, whether or not it is in conformance with these Standards and Guidelines. They also are advised to take notice of the date any particular guideline was adopted, and to consider other relevant medical and scientific information that becomes available after that date. It also would be prudent to consider whether intellectual property interests may restrict the performance of certain tests and other procedures.Galactosemias are inherited disorders of galactose metabolism due to deficiency in one of the three enzymes involved in the Leloir pathway: galactose-1-phosphate uridyltransferase, galactokinase, and uridine diphosphate (UDP)-galactose-4'-epimerase. Galactose-1-phosphate uridyltransferase deficiency, or classic galactosemia, is the most frequent and the most severe of the three enzyme deficiencies; it is characterized by failure to thrive, liver failure, susceptibility to sepsis, and death, if untreated. Newborn screening for classic galactosemia has been implemented in all of the United States, while screening for galactokinase deficiency and UDP-galactose-4'-epimerase deficiency is not universal. Early identification and treatment of galactosemia leads to improved outcome. This document reviews the laboratory methods and best practices for the diagnosis of galactosemia.

The Implications of Parental Consanguinity on the Care of Neonates

BACKGROUND

Approximately 6% of births worldwide, 7.9 million children, are born with a serious genetic congenital abnormality each year. A factor thought to increase the prevalence of birth defects is parental consanguinity, which is a social custom practiced in at least 20% of the world's population.

PURPOSE

The purpose of this article is to explore the relationship between consanguinity and congenital defects. This article also aims to enhance neonatal healthcare practitioners' comprehension of its implications for practice and research.

METHODS

A review of literature was compiled from a search of the online databases Cumulative Index of Nursing and Allied Health (CINAHL), PubMed, EBSCO MegaFILE, and Google Scholar.

RESULTS

Literature pertinent to this topic primarily consists of research studies that examine the inbreeding depression phenomenon through comparison of the prevalence of birth defects among the offspring of consanguineous and nonconsanguineous couples. Current studies indicate that the progeny of consanguineous couples are at an increased risk of congenital defects compared with those of nonconsanguineous couples.

IMPLICATIONS FOR PRACTICE

Consanguinity is one risk factor among many that can lead to a major birth defect. Relationships between consanguineous populations and neonatal healthcare practitioners such as registered nurses, advanced practice nurses, and physicians could significantly alter neonatal health outcomes. Specific recommendations such as genetic counseling and therapeutic communication are discussed.

IMPLICATIONS FOR RESEARCH

Further studies need to investigate the connection between consanguinity and birth defects while controlling for nongenetic variables. Moreover, a focus on consanguineous communities in the United States would prove beneficial.

Applicability of the SMART Model of Transition Readiness for Sickle-Cell Disease

OBJECTIVES

This study aimed to examine the applicability of the Social-ecological Model of Adolescent and Young Adult Readiness to Transition (SMART) model for adolescents and young adults (AYA) with sickle-cell disease (SCD).

METHODS

14 AYA with SCD (14-24 years old) and 10 clinical experts (6-20 years of experience) completed semi-structured interviews. AYA completed brief questionnaires. Interviews were coded for themes, which were reviewed to determine their fit within the SMART model.

RESULTS

Overall, most themes were consistent with the model (e.g., sociodemographics/culture, neurocognition/IQ, etc.). Factors related to race/culture, pain management, health-care navigation skills, societal stigma, and lack of awareness about SCD were salient for AYA with SCD.

CONCLUSIONS

Findings suggest the SMART model may be appropriate in SCD with the consideration of disease-related stigma. This study is a step toward developing a disease-specific model of transition readiness for SCD. Future directions include the development of a measure of transition readiness for this population.

Risk Factors for Sensorineural Hearing Loss Among High-Risk Infants in Golestan Province, Iran in 2010 - 2011

Background:

Hearing impairment, as one of the most common birth defects, is a hidden disability with negative impacts on speech and cognitive development.

Objectives:

The aim of this study was to assess the prevalence of sensorineural hearing loss (SNHL) and determine the associated risk factors among infants admitted to neonatal intensive care units (NICUs) and neonatal wards of teaching hospitals, affiliated to Golestan University of Medical Sciences, Gorgan, Iran.

Patients and Methods:

In this cross-sectional study, 791 infants were recruited via non-random sampling. Demographic and clinical characteristics of the subjects were gathered, and the Automated Auditory Brainstem Response (AABR) test was performed upon admission. Afterwards, the subjects were followed-up and re-assessed, using the AABR test. For infants with abnormal AABR results, the Auditory Brainstem Response (ABR) test was performed on the day of discharge.

Results:

The mean age of the infants was 3.75 ± 4.86 days upon admission, and 56.4% of the subjects were female. The mean length of hospital stay was 9.63 ± 1.1 days; the subjects were hospitalized for 3.50 ± 10.21 days in the NICUs and 6.1 ± 5.27 days in the neonatal wards. In total, 3.4% of the infants presented with SNHL. No significant difference was found between SNHL and neonates’ age (P = 0.52), sex (P = 0.5), or sepsis (P = 0.94). However, SNHL was significantly associated with gestational age (P = 0.045), birth weight (P < 0.001), length of hospital stay (P < 0.001), pathological jaundice (P=0.033), antibiotic treatments (P = 0.007), and total serum bilirubin level (P = 0.01). Additionally, binary logistic regression analysis demonstrated the association between SNHL and these factors.

Conclusions:

In this study, the prevalence of SNHL among hospitalized neonates was similar to previous reports in Iran and other countries. Based on the findings, administration of ototoxic drugs during the neonatal period can lead to SNHL. Therefore, it seems essential to regularly screen newborns under treatment and limit the indiscriminate use of ototoxic drugs.

Showing Value in Newborn Screening: Challenges in Quantifying the Effectiveness and Cost-Effectiveness of Early Detection of Phenylketonuria and Cystic Fibrosis

Decision makers sometimes request information on the cost savings, cost-effectiveness, or cost-benefit of public health programs. In practice, quantifying the health and economic benefits of population-level screening programs such as newborn screening (NBS) is challenging. It requires that one specify the frequencies of health outcomes and events, such as hospitalizations, for a cohort of children with a given condition under two different scenarios-with or without NBS. Such analyses also assume that everything else, including treatments, is the same between groups. Lack of comparable data for representative screened and unscreened cohorts that are exposed to the same treatments following diagnosis can result in either under- or over-statement of differences. Accordingly, the benefits of early detection may be understated or overstated. This paper illustrates these common problems through a review of past economic evaluations of screening for two historically significant conditions, phenylketonuria and cystic fibrosis. In both examples qualitative judgments about the value of prompt identification and early treatment to an affected child were more influential than specific numerical estimates of lives or costs saved.

Newborn screening for homocystinuria

BACKGROUND

Homocystinuria is a rare inherited disorder due to a deficiency in cystathionine beta synthase. Individuals with this condition appear normal at birth but develop serious complications in childhood. Diagnosis and treatment started sufficiently early in life can effectively prevent or reduce the severity of these complications. This is an update of a previously published review.

OBJECTIVES

To determine if newborn population screening for the diagnosis of homocystinuria due to cystathionine beta synthase deficiency leads to clinical benefit compared to later clinical diagnosis.

SEARCH METHODS

We searched the Cochrane Cystic Fibrosis and Genetic Disorders Group's Inborn Errors of Metabolism Trials Register.Date of the most recent search of the Inborn Errors of Metabolism Register: 08 June 2015.

SELECTION CRITERIA

Randomised controlled trials and controlled clinical trials assessing the use of any neonatal screening test to diagnose infants with homocystinuria before the condition becomes clinically evident. Eligible studies compare a screened population versus a non-screened population.

DATA COLLECTION AND ANALYSIS

No studies were identified for inclusion in the review.

MAIN RESULTS

No studies were identified for inclusion in the review.

AUTHORS' CONCLUSIONS

We were unable to identify eligible studies for inclusion in this review and hence it is not possible to draw any conclusions based on controlled studies; however, we are aware of uncontrolled case-series which support the efficacy of newborn screening for homocystinuria and its early treatment. Any future randomised controlled trial would need to be both multicentre and long term in order to provide robust evidence for or against screening and to allow a cost effectiveness analysis to be undertaken.

Newborn Screening: What Does the Emergency Physician Need to Know?

Newborn screening programs were established in the United States in the early 1960s. Newborn screening programs were then developed by states and have continued to be the responsibility of the state. All states require a newborn screening, but what is required of these programs and screening panels has differed greatly by state. Historically, the most commonly screened disorders are the following: congenital hypothyroidism, congenital adrenal hyperplasia, sickle cell disease and associated hemoglobinopathies, biotinidase deficiency, galactosemia, cystic fibrosis and phenylketonuria, maple syrup urine disease, and homocystinuria. However, under new guidelines in 2006 and with new advances in technology, the scope of newborn screening programs has expanded to include at a minimum 9 organic acidurias, 5 fatty acid oxidation disorders, 3 hemoglobinopathies, and 6 other conditions. This CME article reviews the logistics of newborn screening and explores the effect of new technology and recent policy on state screens and what that means for providers. This article also highlights several of the disorders most relevant to emergency room physicians and discusses future considerations of newborn screening.

Clinical practice: experience with newborn screening for congenital hypothyroidism in the Republic of Macedonia - a multiethnic country

To evaluate the thyroid screening program and to estimate the prevalence of congenital hypothyroidism (CH) among newborns in the Republic of Macedonia, we measured thyroid-stimulating hormone (TSH) levels in dried blood spot specimens using the DELFIA fluoroimmunoassay, over a period of 12 years. The TSH cutoff level was 10 mU/L blood. A total of 215,077 newborns were screened (94.76 %). Out of 254 recalled newborns (a recall rate of 0.15 %), 83 newborns with CH were detected, yielding a CH prevalence at screening of 1/2,591 (female to male ratio, 1.86:1). Of the CH cases, 47/107,754 (56.6 %) neonates were Macedonian, 29/70,330 (34.9 %) were Albanian, and 7/15,055 (8.4 %) were Roma. The thyroid gland was undetectable on ultrasound in 43 (51.8 %) newborns with CH, thyroid hypoplasia was confirmed in 8 (9.6 %), while 29 (34.9 %) had a normal thyroid gland. In three newborns (3.6 %), agenesis of one lobe was confirmed. Therapy with levothyroxin was initiated on average 11.7 days after birth.

CONCLUSION

The national thyroid newborn screening program in Macedonia has been successful and effective, providing timely diagnosis and treatment of children with congenital hypothyroidism.

Galactose-1-phosphate uridyltransferase dried blood spot quality control materials for newborn screening tests

OBJECTIVES

We aimed to prepare dried-blood-spot (DBS) quality control (QC) materials for galactose-1-phosphate uridyltransferase (GALT), to evaluate their stability during storage and use, and to evaluate their performance in five DBS GALT test methods.

DESIGN AND METHODS

We prepared and characterized GALT-normal and GALT-deficient DBS materials and compared GALT activities in DBSs after predetermined storage intervals at controlled temperatures and humidities. External evaluators documented the suitability of the DBS QC materials for use in five GALT test methods.

RESULTS

GALT activity losses from DBSs stored in low (<30%) humidity for 14 days at 45°C, 35 days at 37°C, 91 days at room temperature, 182 days at 4°C, and 367 days at -20°C were 54%, 53%, 52% 23%, and 7% respectively. In paired DBSs stored in high humidity (>50%) for identical intervals, losses were: 45°C-68%; 37°C-79%; room temperature-72%, and 4°C-63%. GALT activities in DBSs stored at 4°C were stable throughout 19 excursions to room temperature. Twenty-five of 26 external evaluators, using five different GALT test methods, classified the GALT-deficient DBSs as "outside normal limits". All evaluators classified the GALT-normal DBSs as "within normal limits".

CONCLUSIONS

Most of the GALT activity loss from DBSs stored at elevated or room temperature was attributable to the effects of storage temperature. Most of the loss from DBSs stored at 4°C was attributable to the effects of elevated humidity. Loss from DBSs stored at -20°C was insignificant. The DBS materials were suitable for monitoring performance of all five GALT test methods.

Perceived discrimination, patient trust, and adherence to medical recommendations among persons with sickle cell disease

BACKGROUND

Adults with sickle cell disease (SCD) report experiencing discriminatory behavior from some healthcare providers. The impact of discrimination on health outcomes in SCD, including adherence to physician recommendations, is not known.

OBJECTIVE

Our aim was to evaluate the association between perceived discrimination from healthcare providers and nonadherence to physician recommendations among persons with SCD, and to test the potentially mediating role of patient trust.

PARTICIPANTS

Patients with SCD (age 15 years and older) participating in the Improving Patient Outcomes with Respect and Trust (IMPORT) Study.

MAIN MEASURES

Perceived discrimination from healthcare providers and reported adherence to physician recommendations were assessed by patient self-report using items from the 2001 Commonwealth Fund Health Survey. Interpersonal trust in medical professionals was assessed using the short form of the Wake Forest Trust in Medical Professionals instrument.

DESIGN

We used a cross-sectional analysis of IMPORT participant data. Multivariable Poisson regression models were used to test the independent association of discrimination with adherence and to test patient trust as a potential mediator.

KEY RESULTS

Among 273 SCD patients with complete data on all variables of interest, patients reporting experiences of discrimination in the healthcare system were 53% more likely to also report being nonadherent to physician recommendations. Trust in medical professionals appeared to mediate the discrimination/nonadherence relationship, accounting for 50% of the excess prevalence of nonadherence among those experiencing discrimination.

CONCLUSION

SCD patient perceptions of discriminatory experiences from healthcare providers are associated with greater nonadherence to physician recommendations, and may be a potential factor contributing to disparities in health and health quality among this patient population. Perceived discrimination appears to affect adherence behaviors through the pathway of patient trust. Improving relationships between healthcare providers and SCD patients may improve the trust that SCD patients have in medical professionals, which in turn may improve other outcomes among this underserved patient population.

Screening for and treatments of congenital immunodeficiency diseases

Although newborn screening (NBS) for inborn errors of metabolism has been successfully utilized in the US for decades, only recently has this screening program expanded to include disorders of immunity. Severe combined immunodeficiency (SCID) became the first disorder of immunity to be screened on a population wide basis in 2008. While NBS for SCID has been successful, the implementation of population-based screening programs is not without controversy, and there remain barriers to the nationwide implementation of this test. In addition, as the program has progressed we have learned of new challenges in the management of newborns that fail this screen.

Perceived discrimination in health care is associated with a greater burden of pain in sickle cell disease

CONTEXT

Perceived discriminatory experiences in society have been associated with a higher burden of pain among some minority patient populations.

OBJECTIVES

To describe the extent to which patients with sickle cell disease (SCD) perceive discrimination from health care providers and to examine the association of these experiences with the burden of chronic SCD pain.

METHODS

Cross-sectional analysis of data collected at baseline of a prospective cohort study of SCD patient experiences of care (n = 291). Perceived race-based and disease-based discrimination from health care providers were measured using subscales adapted from the Interpersonal Processes of Care Survey. Discrimination scores were examined for their association with patient characteristics and measures of pain burden using descriptive, bivariate, and multivariate analytic techniques.

RESULTS

Respondents reported a greater burden of race-based discrimination from health care providers than has been previously reported by African Americans, and they reported a greater amount of disease-based vs. race-based discrimination. Age and having difficulty persuading providers about pain were the only patient characteristics independently associated with race-based discrimination, whereas older age, greater emergency room utilization, having difficulty persuading providers about pain, daily chronic pain, fewer good days during a week, and a higher severity of pain on their good days were independently associated with greater disease-based discrimination.

CONCLUSION

Perceived disease-based, but not race-based, discrimination was found to be associated with a greater range of self-reported pain among patients with SCD. If causal, this finding could signal an important new approach to mitigating the burden of pain experienced by persons with SCD.

Diagnosis of cystathionine beta-synthase deficiency by genetic analysis

Intellectual disability like other common diseases is often complex because they are genetically heterogeneous, with many different genetic defects giving rise to clinically indistinguishable phenotypes. We present diagnosis of cystathionine beta-synthase (CBS) deficiency in a multiply affected Iranian family with obvious intellectual disability based on whole genome SNP homozygosity mapping. Diagnosis based on clinical presentations had not been made because of unavailability of appropriate medical services. Genetic analysis led to identification of homozygous c.346G>A in CBS that causes p.Gly116Arg in the encoded protein, cystathionine beta-synthase. CBS is the most common causative gene of homocystinurea. Later, the same mutation was found in three other apparently unrelated Iranian homocystinuria patients. p.Gly116Arg was reported once before in a Turkish patient, suggesting it may be a common CBS deficiency causing mutation in the Middle East. Clinical features of the patients are reported that evidence to variable presentations caused by the same mutation. Finally, observations in heterozygous carriers of the mutation suggest data that a single allele of the p.Gly116Arg causing mutation may have phenotypic consequences, including cardiac related phenotypes. Our study attests to the powers of genetic analysis for diagnosis especially for some forms of intellectual disability, with known genetic causing agents.

Benefits and burdens of newborn screening: public understanding and decision-making

In this article we review the literature regarding the public understanding of the potential benefits and burdens of expanded newborn bloodspot screening. We draw attention to broadened notions of benefit that go beyond early identification of asymptomatic individuals and interventions to reduce morbidity or mortality, and include benefits gained by families through knowledge that may facilitate life choices, as well as gains generated by avoiding diagnostic delays. We also reflect on burdens such as increasing false-positive results and parental anxiety, together with risks of overdiagnosis when the natural history of a condition is poorly understood. We conclude that expanded notions of benefit and burden bring with them implications for parental consent and confidentiality and the secondary use of bloodspots.

Nutrition management guideline for maple syrup urine disease: an evidence- and consensus-based approach

In an effort to increase harmonization of care and enable outcome studies, the Genetic Metabolic Dietitians International (GMDI) and the Southeast Regional Newborn Screening and Genetics Collaborative (SERC) are partnering to develop nutrition management guidelines for inherited metabolic disorders (IMD) using a model combining both evidence- and consensus-based methodology. The first guideline to be completed is for maple syrup urine disease (MSUD). This report describes the methodology used in its development: formulation of five research questions; review, critical appraisal and abstraction of peer-reviewed studies and unpublished practice literature; and expert input through Delphi surveys and a nominal group process. This report includes the summary statements for each research question and the nutrition management recommendations they generated. Each recommendation is followed by a standardized rating based on the strength of the evidence and consensus used. The application of technology to build the infrastructure for this project allowed transparency during development of this guideline and will be a foundation for future guidelines. Online open access of the full, published guideline allows utilization by health care providers, researchers, and collaborators who advise, advocate and care for individuals with MSUD and their families. There will be future updates as warranted by developments in research and clinical practice.

Subfertility and growth restriction in a new galactose-1 phosphate uridylyltransferase (GALT) - deficient mouse model

The first GalT gene knockout (KO) mouse model for Classic Galactosemia (OMIM 230400) accumulated some galactose and its metabolites upon galactose challenge, but was seemingly fertile and symptom free. Here we constructed a new GalT gene-trapped mouse model by injecting GalT gene-trapped mouse embryonic stem cells into blastocysts, which were later implanted into pseudo-pregnant females. High percentage GalT gene-trapped chimera obtained were used to generate heterozygous and subsequently, homozygous GalT gene-trapped mice. Biochemical assays confirmed total absence of galactose-1 phosphate uridylyltransferase (GALT) activity in the homozygotes. Although the homozygous GalT gene-trapped females could conceive and give birth when fed with normal chow, they had smaller litter size (P=0.02) and longer time-to-pregnancy (P=0.013) than their wild-type littermates. Follicle-stimulating hormone levels of the mutant female mice were not significantly different from the age-matched, wild-type females, but histological examination of the ovaries revealed fewer follicles in the homozygous mutants (P=0.007). Administration of a high-galactose (40% w/w) diet to lactating homozygous GalT gene-trapped females led to lethality in over 70% of the homozygous GalT gene-trapped pups before weaning. Cerebral edema, abnormal changes in the Purkinje and the outer granular cell layers of the cerebellum, as well as lower blood GSH/GSSG ratio were identified in the galactose-intoxicated pups. Finally, reduced growth was observed in GalT gene-trapped pups fed with normal chow and all pups fed with high-galactose (20% w/w) diet. This new mouse model presents several of the complications of Classic Galactosemia and will be useful to investigate pathogenesis and new therapies.

The development and organization of newborn screening programs in Turkey

BACKGROUND

Newborn screening tests have been designed to identify infants with severe disorders that are relatively prevalent and treatable or controllable. Comparing to other countries, the incidence of these diseases are very high in Turkey where the rate of consanguineous marriage is high.

METHODS

In this article, it is aimed to evaluate the development and organization of newborn screening programs in Turkey which include phenylketonuria, congenital hypothyroidism and biotinidase deficiency screenings. The point reached today, limitations of the program, expectations and projects for the future are discussed.

RESULTS

Today, the point reached in screening programs of the country is appreciable. While the screening rate of the live born babies was 4,7% in 1987, this rate reached to 95% by 2008. Predicted target for newborn screening program at the strategic plan of Ministry of Health for 2010-2014 was to enhance this rate above 95% by the end of 2012. It seems that the envisaged goal has been reached.

CONCLUSION

National newborn screening program appears to be conducted successfully and extensively as a result of political determination and performance of health care workers who are in charge of this program. Nevertheless, limited numbers of the nutrition and metabolism clinics and specialists on these branches have caused some access difficulties, waste of time, and financial loss. Therefore, special planning to improve quality and the number of the clinics would be useful.

Evidence needed to inform the next dietary reference intakes for iodine

In 2001, Dietary Reference Intakes (DRIs) for iodine were set for the different gender and life-stage groups by the Institute of Medicine. Because of the serious consequences of iodine deficiency for the developing fetus and infant, there is particular interest in further understanding optimal iodine nutrition and improving the monitoring of iodine status, particularly during infancy, pregnancy, and lactation. This review discusses the basis for the current DRIs for iodine and the evidence that may be needed for considering and conducting the reevaluation of one or more of the DRIs.

Newborn screening for homocystinuria

BACKGROUND

Homocystinuria is a rare inherited disorder due to a deficiency in cystathionine beta synthase. Individuals with this condition appear normal at birth but develop serious complications in childhood. Diagnosis and treatment started sufficiently early in life can effectively prevent or reduce the severity of these complications.

OBJECTIVES

To determine if newborn population screening for the diagnosis of homocystinuria due to cystathionine beta synthase deficiency leads to clinical benefit compared to later clinical diagnosis.

SEARCH METHODS

We searched the Cochrane Cystic Fibrosis and Genetic Disorders Group's Inborn Errors of Metabolism Trials Register.Date of the most recent search of the Inborn Errors of Metabolism Register: 15 May 2013.

SELECTION CRITERIA

Randomised controlled trials and controlled clinical trials assessing the use of any neonatal screening test to diagnose infants with homocystinuria before the condition becomes clinically evident. Eligible studies compare a screened population versus a non-screened population.

DATA COLLECTION AND ANALYSIS

No studies were identified for inclusion in the review.

MAIN RESULTS

No studies were identified for inclusion in the review.

AUTHORS' CONCLUSIONS

We were unable to identify eligible studies for inclusion in this review and hence it is not possible to draw any conclusions based on controlled studies; however, we are aware of uncontrolled case-series which support the efficacy of newborn screening for homocystinuria and its early treatment. Any future randomised controlled trial would need to be both multicentre and long term in order to provide robust evidence for or against screening and to allow a cost effectiveness analysis to be undertaken.

Stabilities of hemoglobins A and S in dried blood spots stored under controlled conditions

OBJECTIVE

We aimed to measure separately the contributions of heat and humidity to changes in levels of hemoglobins A and S in dried-blood-spot (DBS) samples.

DESIGN AND METHODS

We stored paired sets of DBSs at 37°C for predetermined intervals in low-humidity and high-humidity environments. Hemoglobin A and S levels of all samples in each complete set were measured in a single high performance liquid chromatography run.

RESULTS

During the one-month storage intervals, both hemoglobin species lost about 35% of initial levels in low-humidity storage and almost all of initial levels in high-humidity storage.

CONCLUSIONS

Minimizing both humidity and temperature in the transportation and storage environments of DBS samples is essential to maintaining the integrity of the hemoglobin tetramer molecules.

Technical report: Ethical and policy issues in genetic testing and screening of children

The genetic testing and genetic screening of children are commonplace. Decisions about whether to offer genetic testing and screening should be driven by the best interest of the child. The growing literature on the psychosocial and clinical effects of such testing and screening can help inform best practices. This technical report provides ethical justification and empirical data in support of the proposed policy recommendations regarding such practices in a myriad of settings.

The influence of sex, gestational age, birth weight, blood transfusion, and timing of the heel prick on the pancreatitis-associated protein concentration in newborn screening for cystic fibrosis

BACKGROUND

Pancreatitis-associated protein (PAP) is currently discussed as a marker in newborn screening (NBS) for cystic fibrosis (CF). However, it is not known if PAP concentrations are influenced by sex, gestational age, birth weight, blood transfusion or time of collection and what this would mean for NBS for CF.

METHODS

In 2008 all newborns in part of the Netherlands were screened for CF by an IRT/PAP protocol. PAP concentration was determined by the MucoPAP ELISA (DynaBio), which was modified to a Dissociation Enhanced Lanthanide Fluoroimmunoassay (DELFIA) method following a protocol of PerkinElmer.

RESULTS

In healthy newborns, the median PAP concentration was 0.5 μg/l (Interquartile range (IQR 0.3-0.8) whereas this was 3.2 μg/l (IQR 2.0-12.5) in CF infants. PAP concentrations were lower in premature infants 0.94 and 0.91 times for 25 to 31 + 6 weeks GA and 32 to 36 + 6 weeks respectively. A higher PAP concentration was observed in low-birth-weight infants (<2500 gram)(p = 0.001), per 100 gram birth weight gained the PAP concentration decreased with 0.1 %. PAP levels were higher after a blood transfusion, the 95th percentile increased from 1.3 to 3.6 μg/l leading to a higher false-positive rate. The PAP concentration increased when newborn screening was performed more than 168 hours (day 7) after birth (β = 1.63), the 95th percentile increased from 1.3-1.6 μg/l to 4.0 μg/l after 168 hours (72,874 newborns were screened).

CONCLUSION

Sex, birth weight, and gestational age lead to small differences in PAP concentrations without consequences for the screening algorithm. However, blood transfusion as well as performance of the heel prick after 168 hours (7 days) lead to clinically significant higher PAP levels and to a higher risk on a false-positive screening test result.