Metabolic Control and Frequency of Clinical Monitoring Among Canadian Children With Phenylalanine Hydroxylase Deficiency: A Retrospective Cohort Study.

Achieving and maintaining metabolic control is critical for children with phenylalanine hydroxylase (PAH) deficiency. This retrospective longitudinal cohort study investigated metabolic control and monitoring frequency of children with PAH deficiency (≤ 12 years) treated at one of 12 pediatric metabolic centres across Canada. We abstracted data from medical charts and analyzed outcomes by age and diagnostic classification, using mixed effects regression.

A cost-utility analysis of newborn screening for spinal muscular atrophy in Canada.

Background: Spinal muscular atrophy (SMA) is a neuromuscular disorder caused by the loss of the SMN1 gene, with an estimated birth prevalence of about 1 in 10,000. Early intervention with disease-modifying therapies (DMTs) significantly improves outcomes. This study evaluates the economic implications and health benefits of newborn screening (NBS) for SMA in Canada from the societal perspective.

Protocol for the development of a core outcome set for type 1 diabetes risk screening.

Introduction: Type 1 diabetes is a chronic autoimmune disease that often presents with diabetic ketoacidosis at diagnosis. Since detection of type 1 diabetes risk is possible using genetic risk scores and autoantibody assays, prevention of diabetic ketoacidosis or delayed onset of type 1 diabetes may be possible and may improve outcomes. Several pilot screening programmes for type 1 diabetes risk have emerged worldwide but outcomes measured in these screening programmes are heterogeneous, making it difficult to compare and synthesise findings across studies.

Systematic review for economic evaluations on newborn screening for spinal muscular atrophy.

ObjectiveEvaluate the quality and cost-effectiveness of economic evaluations of newborn screening (NBS) for Spinal Muscular Atrophy (SMA).MethodsA systematic review was conducted following Cochrane Handbook guidelines and PRISMA-S checklist. From 146 identified papers, 22 were screened for full-text, and 5 were included.

Newborn screening for common genetic variants associated with permanent hearing loss: Implementation in Ontario and review of the first 3 years.

Purpose: Early hearing detection and intervention (EHDI) programs using audiometric screening techniques alone have a limited ability to detect noncongenital childhood permanent hearing loss (PHL). In 2019, Ontario launched universal newborn screening (NBS) for PHL risk factors, including congenital cytomegalovirus and 22 common variants in GJB2 and SLC26A4. Here, we describe our experience in screening for genetic risk factors.

Outcomes of a Population-Based Congenital Cytomegalovirus Screening Program.

Importance: Detection of congenital cytomegalovirus (cCMV) infection has previously relied on targeted screening programs or clinical recognition; however, these approaches miss most cCMV-infected newborns and fail to identify those infants who are asymptomatic at birth but at risk for late-onset sensorineural hearing loss.

Objective: To determine the feasibility of using routinely collected newborn dried blood spots (DBS) in a population-based cCMV screen to identify infants at risk for hearing loss and describe outcomes of infants screened.

Design, Setting, And Participants: This diagnostic study of a population-based screening program in Ontario, Canada, took place from July 29, 2019, to July 31, 2023.

High precision newborn screening for mucopolysaccharidosis type I by enzymatic activity followed by endogenous, non-reducing end glycosaminoglycan analysis.

Measurement of enzymatic activity in newborn dried blood spots (DBS) is the preferred first-tier method in newborn screening (NBS) for mucopolysaccharidosis (MPS) disorders. However, false positives are observed due mainly to the presence of pseudodeficiencies. Our previous publications on glycosaminoglycan (GAG) biomarker levels in dried blood spots (DBS) for mucopolysaccharidoses demonstrated that second-tier GAG biomarker analysis can dramatically reduce the false positive rate in NBS.

Review of clinical trials and guidelines for children and youth with mucopolysaccharidosis: outcome selection and measurement.

Background: To inform the development of a core outcome set (COS) for children and youth with mucopolysaccharidoses (MPS), we aimed to identify all outcomes and associated outcome measurement instruments that are reported in recent clinical trials and recommended as measurements in clinical management guidelines.

Methods: To identify English-language clinical trials and guidelines pertaining to MPS published between 2011 and mid-2021, we applied a comprehensive peer-reviewed search strategy to relevant databases and registers on May 16, 2021. Two reviewers independently screened retrieved citations and then full-text articles to determine eligibility for inclusion.

Estimating Gestational Age and Prediction of Preterm Birth Using Metabolomics Biomarkers.

Preterm birth (PTB) is a leading cause of morbidity and mortality in children aged under 5 years globally, especially in low-resource settings. It remains a challenge in many low-income and middle-income countries to accurately measure the true burden of PTB due to limited availability of accurate measures of gestational age (GA), first trimester ultrasound dating being the gold standard. Metabolomics biomarkers are a promising area of research that could provide tools for both early identification of high-risk pregnancies and for the estimation of GA and preterm status of newborns postnatally.

Assessing the quality and value of metabolic chart data for capturing core outcomes for pediatric medium-chain acyl-CoA dehydrogenase (MCAD) deficiency.

Background: Generating rigorous evidence to inform care for rare diseases requires reliable, sustainable, and longitudinal measurement of priority outcomes. Having developed a core outcome set for pediatric medium-chain acyl-CoA dehydrogenase (MCAD) deficiency, we aimed to assess the feasibility of prospective measurement of these core outcomes during routine metabolic clinic visits.

Methods: We used existing cohort data abstracted from charts of 124 children diagnosed with MCAD deficiency who participated in a Canadian study which collected data from birth to a maximum of 11 years of age to investigate the frequency of clinic visits and quality of metabolic chart data for selected outcomes.

Intrauterine enzyme replacement therapies for lysosomal storage disorders: Current developments and promising future prospects.

Lysosomal storage disorders (LSDs) are a group of monogenic condition, with many characterized by an enzyme deficiency leading to the accumulation of an undegraded substrate within the lysosomes. For those LSDs, postnatal enzyme replacement therapy (ERT) represents the standard of care, but this treatment has limitations when administered only postnatally because, at that point, prenatal disease sequelae may be irreversible. Furthermore, most forms of ERT, specifically those administered systemically, are currently unable to access certain tissues, such as the central nervous system (CNS), and furthermore, may initiate an immune response.

The Ontario Newborn Screening Program: A novel referral center model.

Newborn screening (NBS) for inherited and congenital disorders is a form of secondary disease prevention and a public health responsibility. The development of NBS programs is one of the most important achievements in health care. While the scope of the screening targets has expanded and methods have evolved, the screening process has remained essentially unchanged.

Case report: A case of spinal muscular atrophy in a preterm infant: risks and benefits of treatment.

Spinal muscular atrophy (SMA) is a neuromuscular genetic disorder caused by the loss of lower motor neurons leading to progressive muscle weakness and atrophy. With the rise of novel therapies and early diagnosis on newborn screening (NBS), the natural history of SMA has been evolving. Earlier therapeutic interventions can modify disease outcomes and improve survival.

The mitochondrial tRNA MT-TW m.5537_5538insT variant presents with significant intra-familial clinical variability.

Mitochondrial disorders can present with a wide range of clinical and biochemical phenotypes. Mitochondrial DNA variants may be influenced by factors such as degree of heteroplasmy and tissue distribution. We present a four-generation family in which 10 individuals carry a pathogenic mitochondrial variant (m.

Parental Preferences for Expanded Newborn Screening: What Are the Limits?

The use of next-generation sequencing technologies such as genomic sequencing in newborn screening (NBS) could enable the detection of a broader range of conditions. We explored parental preferences and attitudes towards screening for conditions for which varying types of treatment exist with a cross-sectional survey completed by 100 parents of newborns who received NBS in Ontario, Canada. The survey included four vignettes illustrative of hypothetical screening targets, followed by questions assessing parental attitudes.

Estimating the Incidence of First RSV Hospitalization in Children Born in Ontario, Canada.

Background: Respiratory syncytial virus (RSV) contributes significantly to morbidity in children, placing substantial burdens on health systems, thus RSV vaccine development and program implementation are a public health priority. More data on burden are needed by policymakers to identify priority populations and formulate prevention strategies as vaccines are developed and licensed.

Methods: Using health administrative data, we calculated incidence rates of RSV hospitalization in a population-based birth cohort of all children born over a six-year period (May 2009 to June 2015) in Ontario, Canada.

TRNT-1 Deficiency Is Associated with Loss of tRNA Integrity and Imbalance of Distinct Proteins.

Mitochondrial diseases are a group of heterogeneous disorders caused by dysfunctional mitochondria. Interestingly, a large proportion of mitochondrial diseases are caused by defects in genes associated with tRNA metabolism. We recently discovered that partial loss-of-function mutations in tRNA Nucleotidyl Transferase 1 (), the nuclear gene encoding the CCA-adding enzyme essential for modifying both nuclear and mitochondrial tRNAs, causes a multisystemic and clinically heterogenous disease termed SIFD (sideroblastic anemia with B-cell immunodeficiency, periodic fevers, and developmental delay; SIFD).

Newborn Screening Conditions: Early Intervention and Probability of Developmental Delay.

Objectives: The purpose of this study is to explore which newborn screening (NBS) conditions are automatically eligible for early intervention (EI) across states and to determine the extent to which each disorder should automatically qualify for EI because of a high probability of developmental delay.

Methods: We examined each state's EI eligibility policy and reviewed the literature documenting developmental outcomes for each NBS condition. Using a novel matrix, we assessed the risk of developmental delay, medical complexity, and risk of episodic decompensation, revising the matrix iteratively until reaching consensus.

Ethical and practical considerations related to data sharing when collecting patient-reported outcomes in care-based child health research.

Purpose: The collection and use of patient reported outcomes (PROs) in care-based child health research raises challenging ethical and logistical questions. This paper offers an analysis of two questions related to PROs in child health research: (1) Is it ethically obligatory, desirable or preferable to share PRO data collected for research with children, families, and health care providers? And if so, (2) What are the characteristics of a model best suited to guide the collection, monitoring, and sharing of these data?

Methods: A multidisciplinary team of researchers, providers, patient and family partners, and ethicists examined the literature and identified a need for focus on PRO sharing in pediatric care-based research. We constructed and analyzed three models for managing pediatric PRO data in care-based research, drawing on ethical principles, logistics, and opportunities to engage with children and families.

Real world external validation of metabolic gestational age assessment in Kenya.

Using data from Ontario Canada, we previously developed machine learning-based algorithms incorporating newborn screening metabolites to estimate gestational age (GA). The objective of this study was to evaluate the use of these algorithms in a population of infants born in Siaya county, Kenya. Cord and heel prick samples were collected from newborns in Kenya and metabolic analysis was carried out by Newborn Screening Ontario in Ottawa, Canada.