Digital-Tier Strategy Improves Newborn Screening for Glutaric Aciduria Type 1.

Glutaric aciduria type 1 (GA1) is a rare inherited metabolic disease increasingly included in newborn screening (NBS) programs worldwide. Because of the broad biochemical spectrum of individuals with GA1 and the lack of reliable second-tier strategies, NBS for GA1 is still confronted with a high rate of false positives. In this study, we aim to increase the specificity of NBS for GA1 and, hence, to reduce the rate of false positives through machine learning methods.

Dipeptides in CSF and plasma: diagnostic and therapeutic potential in neurological diseases.

Dipeptides (DPs), composed of two amino acids (AAs), hold significant therapeutic potential but remain underexplored. Given the crucial role of AAs in central nervous system (CNS) function, this study investigated the presence of DPs in cerebrospinal fluid (CSF) and their correlation with corresponding AAs, potentially indicating their role as AA donors. Plasma and CSF samples were collected from 43 children with neurological or metabolic conditions of unknown origin, including 23 with epilepsy.

Efficacy and safety of gene therapy with onasemnogene abeparvovec in children with spinal muscular atrophy in the D-A-CH-region: a population-based observational study.

Background: Real-world data on gene addition therapy (GAT) with onasemnogene abeparvovec (OA), including all age groups and with or without symptoms of the disease before treatment are needed to provide families with evidence-based advice and realistic therapeutic goals. Aim of this study is therefore a population-based analysis of all patients with SMA treated with OA across Germany, Austria and Switzerland (D-A-CH).

Methods: This observational study included individuals with Spinal Muscular Atrophy (SMA) treated with OA in 29 specialized neuromuscular centers in the D-A-CH-region.

Impact of early diagnosis, disease variant, and quality of care on the neurocognitive outcome in maple syrup urine disease: A meta-analysis.

Purpose: Maple syrup urine disease (MSUD) is a rare inherited metabolic disease characterized by recurrent metabolic decompensations, neurocognitive impairment, and limited life expectancy. This meta-analysis aims to evaluate the impact of early diagnosis by newborn screening (NBS) on mortality and neurocognitive outcome in survivors, taking into account the quality of national health care systems.

Methods: Systematic literature search was performed according to Preferred Reporting Items for Systematic Review and Meta-Analysis protocol.

Severity-adjusted evaluation of initial dialysis on short-term health outcomes in urea cycle disorders.

Objective: In individuals with urea cycle disorders (UCDs) and neonatal disease onset, extracorporeal detoxification by continuous kidney replacement therapy is considered the therapeutic method of choice in addition to metabolic emergency treatment to resolve hyperammonemic decompensation. However, the indications for the initiation of dialysis are heterogeneously implemented transnationally, thereby hampering our understanding of (optimal) short-term health outcomes.

Methods: We performed a retrospective comparative analysis evaluating the therapeutic effects of initial dialysis on survival as well as neurocognitive outcome parameters in individuals with UCDs in comparison to a severity-adjusted non-dialyzed control cohort.

Assessing carnosinase 1 activity for diagnosing congenital disorders of glycosylation.

Diagnosing Congenital Disorders of Glycosylation (CDG) is challenging due to clinical heterogeneity and the limited sensitivity of the classic serum transferrin isoelectric focusing (IEF) or capillary zone electrophoresis test. This study investigates the potential of using the glycoprotein carnosinase 1 (CN1) activity as a diagnostic marker for CDG patients. CN1 activity was measured photometrically in serum from 81 genetically confirmed CDG patients and healthy individuals.

Parental and child's psychosocial and financial burden living with an inherited metabolic disease identified by newborn screening.

Newborn screening (NBS) is one of the most effective measures of secondary prevention. While the benefit of NBS on the clinical long-term outcomes of children with inherited metabolic diseases (IMD) has been demonstrated, the potential burden of families living with an early diagnosed and treated child with an IMD has not been thoroughly investigated. The aim of this longitudinal questionnaire-based study on 369 families living with a child with an IMD was to investigate the psychosocial and financial burden following a true-positive NBS.

Age-appropriate or delayed myelination? Scoring myelination in routine clinical MRI.

Background: Assessment of myelination is a core issue in paediatric neuroimaging and can be challenging, particularly in settings without dedicated paediatric neuroradiologists. Deep learning models have recently been shown to be able to estimate myelination age in children with normal MRI, but currently lack validation for patients with myelination delay and implementation including pre-processing suitable for local imaging is not trivial. Standardized myelination scores, which have been successfully used as biomarkers for myelination in hypomyelinating diseases, rely on visual, semiquantitative scoring of myelination on routine clinical MRI and may offer an easy-to-use alternative for assessment of myelination.

Vitamin B12 Deficiency Newborn Screening.

Background: Vitamin B12 deficiency (VitB12D) might cause neuro-developmental impairment in the first year of life. Newborn screening (NBS) for VitB12D was shown to be technically feasible and early treated infants developed favorably. This study aims to evaluate the impact of NBS in prevention of symptomatic infantile VitB12D.

Treatment Outcomes for Maple Syrup Urine Disease Detected by Newborn Screening.

Objective: Maple syrup urine disease (MSUD), a life-threatening metabolic disorder, is included in newborn screening (NBS) programs worldwide. The study aims to evaluate the impact of NBS on the long-term outcome of MSUD patients.

Methods: We performed a prospective, national, multicenter, observational study.

Significance of utilizing in silico structural analysis and phenotypic data to characterize phenylalanine hydroxylase variants: A PAH landscape.

Phenylketonuria (PKU) is a genetic disorder caused by variations in the phenylalanine hydroxylase (PAH) gene. Among the 3369 reported PAH variants, 33.7% are missense alterations.

Comparative analysis of gene and disease selection in genomic newborn screening studies.

Genomic newborn screening (gNBS) is on the horizon given the decreasing costs of sequencing and the advanced understanding of the impact of genetic variants on health and diseases. Key to ongoing gNBS pilot studies is the selection of target diseases and associated genes to be included. In this study, we present a comprehensive analysis of seven published gene-disease lists from gNBS studies, evaluating gene-disease count, composition, group proportions, and ClinGen curations of individual disorders.

Outcomes after newborn screening for propionic and methylmalonic acidemia and homocystinurias.

The current German newborn screening (NBS) panel includes 13 inherited metabolic diseases (IMDs). In addition, a NBS pilot study in Southwest Germany identifies individuals with propionic acidemia (PA), methylmalonic acidemia (MMA), combined and isolated remethylation disorders (e.g.

The continuously evolving phenotype of succinic semialdehyde dehydrogenase deficiency.

The objective of the study is to evaluate the evolving phenotype and genetic spectrum of patients with succinic semialdehyde dehydrogenase deficiency (SSADHD) in long-term follow-up. Longitudinal clinical and biochemical data of 22 pediatric and 9 adult individuals with SSADHD from the patient registry of the International Working Group on Neurotransmitter related Disorders (iNTD) were studied with in silico analyses, pathogenicity scores and molecular modeling of ALDH5A1 variants. Leading initial symptoms, with onset in infancy, were developmental delay and hypotonia.

Impact of supplementation with L-citrulline/arginine after liver transplantation in individuals with Urea Cycle Disorders.

Objective: Liver transplantation (LTx) is an intervention when medical management is not sufficiently preventing individuals with urea cycle disorders (UCDs) from the occurrence of hyperammonemic events. Supplementation with L-citrulline/arginine is regularly performed prior to LTx to support ureagenesis and is often continued after the intervention. However, systematic studies assessing the impact of long-term L-citrulline/arginine supplementation in individuals who have undergone LTx is lacking to date.

Neurological outcome in long-chain hydroxy fatty acid oxidation disorders.

Objective: This study aims to elucidate the long-term benefit of newborn screening (NBS) for individuals with long-chain 3-hydroxy-acyl-CoA dehydrogenase (LCHAD) and mitochondrial trifunctional protein (MTP) deficiency, inherited metabolic diseases included in NBS programs worldwide.

Methods: German national multicenter study of individuals with confirmed LCHAD/MTP deficiency identified by NBS between 1999 and 2020 or selective metabolic screening. Analyses focused on NBS results, confirmatory diagnostics, and long-term clinical outcomes.

Influence of Season, Storage Temperature and Time of Sample Collection in Pancreatitis-Associated Protein-Based Algorithms for Newborn Screening for Cystic Fibrosis.

Newborn screening (NBS) for cystic fibrosis (CF) based on pancreatitis-associated protein (PAP) has been performed for several years. While some influencing factors are known, there is currently a lack of information on the influence of seasonal temperature on PAP determination or on the course of PAP blood concentration in infants during the first year of life. Using data from two PAP studies at the Heidelberg NBS centre and storage experiments, we compared PAP determinations in summer and winter and determined the direct influence of temperature.

Impact of genetic and non-genetic factors on phenotypic diversity in NBAS-associated disease.

Biallelic pathogenic variants in neuroblastoma-amplified sequence (NBAS) cause a pleiotropic multisystem disorder. Three clinical subgroups have been defined correlating with the localisation of pathogenic variants in the NBAS gene: variants affecting the C-terminal region of NBAS result in SOPH syndrome (short stature, optic atrophy, Pelger-Huët anomaly), variants affecting the Sec 39 domain are associated with infantile liver failure syndrome type 2 (ILFS2) and variants affecting the ß-propeller domain give rise to a combined phenotype. However, there is still unexplained phenotypic diversity across the three subgroups, challenging the current concept of genotype-phenotype correlations in NBAS-associated disease.

Psychosocial issues and coping strategies in families affected by long-chain fatty acid oxidation disorders.

Long-chain fatty acid oxidation disorders (lcFAODs) are associated with a high disease burden due to both the risk of metabolic decompensation as well as chronic, partly irreversible complications in some. Little research has been performed on the impact of these disorders on the daily life of parents and caregivers. We performed a web-based questionnaire study among parents/caregivers of patients affected with lcFAODs.

Severity-adjusted evaluation of liver transplantation on health outcomes in urea cycle disorders.

Purpose: Liver transplantation (LTx) is performed in individuals with urea cycle disorders when medical management (MM) insufficiently prevents the occurrence of hyperammonemic events. However, there is a paucity of systematic analyses on the effects of LTx on health-related outcome parameters compared to individuals with comparable severity who are medically managed.

Methods: We investigated the effects of LTx and MM on validated health-related outcome parameters, including the metabolic disease course, linear growth, and neurocognitive outcomes.

The challenge of understanding and predicting phenotypic diversity in urea cycle disorders.

The Urea Cycle Disorders Consortium (UCDC) and the European registry and network for Intoxication type Metabolic Diseases (E-IMD) are the worldwide largest databases for individuals with urea cycle disorders (UCDs) comprising longitudinal data from more than 1100 individuals with an overall long-term follow-up of approximately 25 years. However, heterogeneity of the clinical phenotype as well as different diagnostic and therapeutic strategies hamper our understanding on the predictors of phenotypic diversity and the impact of disease-immanent and interventional variables (e.g.