International Journal of Neonatal Screening最新文献

Newborn bloodspot screening (NBS) aims to detect treatable disorders in newborns to offer early interventions. According to the official Dutch national NBS guidance, parents in the Netherlands should be informed about NBS during pregnancy by maternity care providers (MCPs), providing two leaflets and oral information. This study investigated what, how, and when information about NBS is given during pregnancy according to Dutch MCPs. An online questionnaire was completed by 279 MCPs; 237 (84.9%) provided information to parents themselves, although 4.6% of them only did so postnatally, and 240 (86.0%) considered this the task of the MCP. Among the 237 MCPs, information was provided by personal conversation (59.9%) and by giving at least one leaflet (83.1%), while 25.7% only gave leaflets. Being a first pregnancy (45.1%) and parents' literacy (38.8%) influenced how MCPs provided information. Information was mostly provided at 34-37 weeks gestation (68.8%). Conversations mostly included giving information on when NBS will be performed (97.2%), the purpose of NBS (93.7%), how the test will be performed (92.3%), and participation being voluntary (80.3%). The results suggest that while most Dutch MCPs consider it their task to provide NBS information, its timing, method, and completeness do not always follow the established guidelines.

Newborn screening (NBS) presents an opportunity to identify a subset of babies at birth who are at risk for developmental delays and could benefit from a range of developmental services. Potential developmental services in the United States include Part C Early Intervention (EI), private therapies, and school-based services. Using parent-reported outcomes, this study examined the rates at which a sample of children diagnosed with NBS conditions used each developmental service. An online survey of 153 parents representing children with 27 different NBS conditions found that nearly 75% of children (n = 112) used at least one developmental service, with private therapies being the most frequent. Children were referred to EI relatively early and were often eligible because their medical diagnosis automatically qualified them. When examining condition-specific results for children with severe combined immunodeficiencies, congenital hypothyroidism, and Pompe disease, we found variability in rates of use, with high rates overall. Our findings suggest that many children diagnosed with an NBS condition continue to have developmental delays even after they receive appropriate medical care. Future research with more systematic follow-up is needed to understand whether the NBS program facilitates entry into these services and whether more streamlined processes could benefit children and families.

Approximately half of all births globally occur in the Asia Pacific Region. Concerted efforts to support local activities aimed at developing national newborn screening (NBS) have been ongoing for almost 30 years, first by the International Atomic Energy Agency (IAEA) and then through volunteer efforts. Sustainable newborn bloodspot screening (NBS) continues to be initiated and develop in many of the countries with developing economies in the region. Since the discontinuation of IAEA funding in 2007, a working group of the Asia Pacific Society of Human Genetics (APSHG) consisting of interested representatives from countries in the region with less than 50% NBS coverage has participated in periodic workshops to exchange information, set goals, and provide peer support. Facilitated by international NBS experts, interested corporate sponsors, and the APSHG, the 7th workshop of representatives from 10 East Asian countries with developing NBS systems was recently held in Kathmandu, Nepal. This report summarizes the NBS activities in these countries and describes the continuing efforts to move NBS ahead in the region.

The biomarker-based Dutch Newborn Screening (NBS) panel (as of 2024) comprises 19 inherited metabolic disorders (IMDs). With the use of next-generation sequencing (NGS) as a first-tier screen, NBS could expand to include IMDs that lack a reliable biochemical footprint in dried blood spots, while also reducing secondary findings. To be eligible for inclusion in NBS, an IMD needs to fulfill the Wilson and Jungner criteria, with treatability being one of the most important criteria. In this study, we aimed to identify IMDs eligible for DNA-first NBS when considering only treatability in the context of NBS as a prerequisite. First, three independent reviewers performed a systematic literature review of the 1459 genotypic IMDs and their causative gene(s), as described in the International Classification of Inherited Metabolic Disorders (dated 1 February 2021), applying 16 criteria to exclude non-treatable disorders. Eligible disorders were then discussed in three online meetings with a project group of clinical laboratory geneticists, medical laboratory specialists specialized in IMD, and pediatricians with expertise in IMDs. Based on treatability, we identified 100 genes, causing 95 IMDs, as eligible for NBS, including 42 causal genes for the IMDs in the current biomarker-based NBS. The other 58 genes are primarily associated with treatable defects in amino acid metabolism and fatty acid oxidation. Other IMDs were excluded, most often because of insufficient literature. As the evaluation of treatability was not straightforward, we recommend the development of standardized treatability scores for the inclusion of IMDs in NBS.

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. Therefore, we studied NBS profiles from 1,025,953 newborns screened between 2014 and 2023 at the Heidelberg NBS Laboratory, Germany. We identified a significant sex difference, resulting in twice as many false-positives male than female newborns. Moreover, the proposed digital-tier strategy based on logistic regression analysis, ridge regression, and support vector machine reduced the false-positive rate by over 90% compared to regular NBS while identifying all confirmed individuals with GA1 correctly. An in-depth analysis of the profiles revealed that in particular false-positive results with high associated follow-up costs could be reduced significantly. In conclusion, understanding the origin of false-positive NBS and implementing a digital-tier strategy to enhance the specificity of GA1 testing may significantly reduce the burden on newborns and their families from false-positive NBS results.

In The Netherlands, newborn screening (NBS) for tyrosinemia type 1 (TT1) uses dried blood spot (DBS) succinylacetone (SUAC) as a biomarker. However, high false-positive (FP) rates and a false-negative (FN) case show that the Dutch TT1 NBS protocol is suboptimal. In search of optimization options, we evaluated the protocols used by other NBS programs and their performance. We distributed an online survey to NBS program representatives worldwide (N = 41). Questions focused on the organization and performance of the programs and on changes since implementation. Thirty-three representatives completed the survey. TT1 incidence ranged from 1/13,636 to 1/750,000. Most NBS samples are taken between 36 and 72 h after birth. Most used biomarkers were DBS SUAC (78.9%), DBS Tyrosine (Tyr; 5.3%), or DBS Tyr with second tier SUAC (15.8%). The pooled median cut-off for SUAC was 1.50 µmol/L (range 0.3-7.0 µmol/L). The median cut-off from programs using laboratory-developed tests was significantly higher (2.63 µmol/L) than the medians from programs using commercial kits (range 1.0-1.7 µmol/L). The pooled median cut-off for Tyr was 216 µmol/L (range 120-600 µmol/L). Overall positive predictive values were 27.3% for SUAC, 1.2% for Tyr solely, and 90.1% for Tyr + SUAC. One FN result was reported for TT1 NBS using SUAC, while three FN results were reported for TT1 NBS using Tyr. The NBS programs for TT1 vary worldwide in terms of analytical methods, biochemical markers, and cut-off values. There is room for improvement through method standardization, cut-off adaptation, and integration of new biomarkers. Further enhancement is likely to be achieved by the application of post-analytical tools.

Parenteral nutrition (PN) is a nutrient solution administered intravenously (IV) to premature babies. PN causes elevations of some amino acids in blood samples that are also biomarkers used in newborn screening (NBS). Therefore, PN status must be annotated by clinicians on dried blood spot (DBS) cards to reduce NBS laboratory burdens associated with potential false results; however, NBS laboratories continue to receive DBSs with misannotated PN status. N-acetyltyrosine (NAT), a water-soluble tyrosine analog used to increase tyrosine bioavailability in PN solutions, can be used as a blood-based biomarker of PN administration in NBS assays. Residual DBS specimens and manufactured DBSs were used in analyses. The assay was developed and validated using flow injection analysis tandem mass spectrometry (FIA-MS/MS) for the detection of NAT. NAT was only present in neonate DBSs with annotated PN administration and was multiplexed into first-tier newborn screening assays. NAT was highly correlated with amino acids present in PN solutions, such as arginine, leucine, methionine, phenylalanine, and valine. In our sample cohort, we determined an NAT cutoff could aid the identification of misannotated neonates administered PN. We also report the Amadori rearrangement product valine-hexose (Val-Hex) was quantifiable in neonates administered PN, which we suspect forms in the PN solution and/or IV lines. Here, we present the first known use of NAT as a biomarker of PN administration, which is currently being piloted by two U.S. NBS laboratories. NAT and Val-Hex can aid the identification of misannotated DBSs from neonates administered PN, thus decreasing false positive rates.

Newborn screening (NBS) represents an important public health measure for the early detection of specified disorders; such screening can prevent disability and death, not only from metabolic disorders but also from endocrine, hematologic, immune, and cardiac disorders. Screening for critical congenital conditions affecting newborns' health is a great challenge, especially in developing countries such as Morocco, where NBS program infrastructure is lacking. In addition, the consanguinity rate is high in Morocco. This study aimed to demonstrate the feasibility of integrating NBS into a diagnostic laboratory for routine analysis. Six primary severe conditions were included: congenital hypothyroidism (CH), cystic fibrosis (CF), phenylketonuria (PKU), glucose-6-phosphate dehydrogenase deficiency (G6PD), congenital adrenal hyperplasia (CAH), and hemoglobinopathies.

Methods: A retrospective investigation was carried out to examine the outcomes of NBS in Casablanca, Morocco. A total of 5511 newborn blood samples were collected via heel-prick sampling and tested for the above disorders. Most of the samples were collected within the third and sixth days of birth. The dried blood spots were analyzed via a quantitative immunofluorescence technique and isoelectric focusing.

Results: A total of 72 newborns had one of the six pathological conditions. The most prevalent disorders were hemoglobinopathies, which were identified in 47 newborns (0.9%), with 29 having HbC carrier status (0.5%), 15 having Hb S carrier status (0.3%), and 3 having an Hb Bart's carrier profile (0.05%). This was followed by G6PD deficiency, which was found to affect 16 newborns (0.32% of cases). CF was found in one case (0.02%), whereas five newborns (0.09%) tested positive for CAH. Additionally, two newborns (0.04%) tested positive for CH, and one newborn tested positive for PKU (0.02%).

Conclusion: Our findings underscore the importance and success of NBS programs in preventing morbidity and mortality and improving the quality of life of affected neonates. The significant gap in data and research on these disorders within the Moroccan population highlights the urgent need to integrate NBS into routine practice in diagnostic laboratories across Morocco. This integration is crucial for enhancing the health and well-being of Moroccan newborns.

Acid sphingomyelinase deficiency (ASMD) is a rare lysosomal storage disorder with a broad clinical spectrum. Early diagnosis and initiation of treatment are crucial for improving outcomes, yet the disease often goes undiagnosed due to its rarity and phenotypic heterogeneity. This study aims to evaluate the feasibility and disease incidence of newborn screening (NBS) for ASMD in Italy. Dried blood spot samples from 275,011 newborns were collected between 2015 and 2024 at the Regional Center for Expanded NBS in Padua. Acid sphingomyelinase activity was assayed using tandem mass spectrometry. Deidentified samples with reduced enzyme activity underwent second-tier testing with LysoSM quantification and SMPD1 gene analysis. Two samples were identified with reduced sphingomyelinase activity and elevated LysoSM levels. Both carried two SMPD1 variants, suggesting a diagnosis of ASMD. Molecular findings included novel and previously reported variants, some of uncertain significance. The overall incidence was 1 in 137,506 newborns and the PPV was 100%. This study demonstrates the feasibility of NBS for ASMD in Italy and provides evidence of a higher disease incidence than clinically reported, suggesting ASMD is an underdiagnosed condition. Optimized screening algorithms and second-tier biomarker testing can enhance the accuracy of NBS for ASMD. The long-term follow-up of identified cases is necessary for genotype-phenotype correlation and improving patient management.

Newborn congenital hypothyroidism (CH) screening has been widely used worldwide. The objective of this study was to evaluate the effectiveness of applying biochemical and gene panel sequencing as screening tests for CH and to analyze the mutation spectrum of CH in China. Newborns were prospectively recruited from eight hospitals in China between February and December 2021. Clinical characteristics were collected. Second-generation sequencing was used to detect four CH-related genes, and the genetic patterns of the pathogenic genes were analyzed. We analyzed the relationship between genotype and biochemical phenotype. A total of 29,601 newborns were screened for CH. Gene panel sequencing identified 18 patients, including 10 patients affected by biochemically and genetically screened disorders and 8 patients affected by solely genetically screened disorders. The predictive positive value of genetic screening was 34.62%, which was much greater than that of biochemical screening alone (17.99%). A total of 94 cases of congenital thyroid dysfunction were confirmed by biochemical and genetic screening, including 30 CHs and 64 isolated hyperthyrotropinemia (HTT), with an incidence of 1/987 for CH and 1/463 for HTT, and a total incidence of 1/315 for hypothyroidism. The incidence rate and number of patients in Jinan were the highest, and the incidence rates in Shijiazhuang and Shanghai were the lowest. The gene mutation rate in this study was 19.1%, mainly DUOX2 mutation. The most common variant of DUOX2 was c.1588A>T(p.Lys530*). There was only a difference in sFT4 between groups with gene mutations and those without mutations. Genetic screening is a supplement to biochemical screening. Combining biochemical screening with genetic screening is useful for improving screening efficiency. The incidence of CH in China according to a multicenter study of nearly 30,000 NBS surveys was 1/315. DUOX2 gene mutations are commonly detected in these patients.