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Search Results (330)

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Keywords = inborn error of metabolism

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20 pages, 311 KB  
Article
Health-Related Coping Behaviors Among Parents of Children with Inborn Errors of Metabolism: A Survey by Dietary Therapy, Child Age, and Diagnostic Category
by Yuko Matsumoto, Yuko Kushihashi, Akiko Suwa and Go Tajima
Int. J. Neonatal Screen. 2026, 12(2), 32; https://doi.org/10.3390/ijns12020032 - 6 May 2026
Viewed by 172
Abstract
Newborn mass screening improves outcomes for inborn errors of metabolism (IEM); nonetheless, home-based dietary therapy imposes a substantial parental burden. In this study, we explored differences in parents’ health coping behaviors, assessed using the Coping Health Inventory for Parents (CHIP), based on the [...] Read more.
Newborn mass screening improves outcomes for inborn errors of metabolism (IEM); nonetheless, home-based dietary therapy imposes a substantial parental burden. In this study, we explored differences in parents’ health coping behaviors, assessed using the Coping Health Inventory for Parents (CHIP), based on the presence of dietary therapy, child age group, and diagnostic category. A 21-item, CHIP-based questionnaire was distributed via the JaSMIn registry to parents of children with IEM up to school age. Overall, 201 valid responses (56.1% response rate) were analyzed regarding the implementation and perceived usefulness of coping behaviors, stratified by child age, enrollment, diagnosis, and dietary therapy. Parents in the dietary-therapy group reported more coping behaviors than did those in the non-dietary-therapy group. Notably, parents of children aged 1–3 years (not yet in preschool) and those of children with organic acid metabolism disorders rated “daily home practice of treatments” as a highly useful coping behavior. Health-related coping behaviors among parents of children with IEM vary substantially according to child age and disease characteristics. Therefore, family support strategies should be tailored to specific developmental stages and treatment requirements. Full article
(This article belongs to the Collection Newborn Screening in Japan)
10 pages, 1080 KB  
Case Report
A Novel Variant in an Israeli Bedouin Family: The First Reported Cases of Carbonic Anhydrase VA (CA5A) Deficiency in Israel
by Nitzan Abelson, Eyal Kristal, Eli Hershkovitz, Ohad Wormser, Vadim Dolgin, Shirly Amar and Orna Staretz-Chacham
Genes 2026, 17(5), 537; https://doi.org/10.3390/genes17050537 - 1 May 2026
Viewed by 275
Abstract
Carbonic anhydrase VA (CA5A) deficiency (OMIM 615751) is an ultra-rare inborn error of metabolism, presenting in newborns, infants, and young children with a pentad of encephalopathy, hyperammonemia, lactic acidosis, ketonuria, and hypoglycemia. We present two cases: a case of a healthy Bedouin infant [...] Read more.
Carbonic anhydrase VA (CA5A) deficiency (OMIM 615751) is an ultra-rare inborn error of metabolism, presenting in newborns, infants, and young children with a pentad of encephalopathy, hyperammonemia, lactic acidosis, ketonuria, and hypoglycemia. We present two cases: a case of a healthy Bedouin infant admitted with hyperammonemic encephalopathy that required urgent hemodialysis, and her younger sibling, who presented with a milder episode. Molecular analysis confirmed the diagnosis of CA5A deficiency due to a homozygous missense variant in the CA5A gene. Both patients had a favorable outcome with continued normal development. These were the first identified cases of CA5A deficiency in the Bedouin population, emphasizing the importance of a high index of suspicion, early genetic consultation and diagnosis, and prompt treatment at the earliest possible stage of a hyperammonemic crisis. Full article
(This article belongs to the Section Human Genomics and Genetic Diseases)
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17 pages, 534 KB  
Review
Nutritional and Therapeutic Strategies in Paediatric Phenylketonuria: A Narrative Literature Review
by Holly Jones and Eugen-Matthias Strehle
Nutrients 2026, 18(9), 1347; https://doi.org/10.3390/nu18091347 - 24 Apr 2026
Viewed by 315
Abstract
Phenylketonuria (PKU) is an autosomal recessive disorder characterised by an inborn error of phenylalanine (Phe) metabolism. Such errors are attributed to pathogenic gene variants causing phenylalanine hydroxylase (PAH) deficiency, impairing the hydroxylation of phenylalanine to tyrosine in the Phe metabolic pathway. This defect [...] Read more.
Phenylketonuria (PKU) is an autosomal recessive disorder characterised by an inborn error of phenylalanine (Phe) metabolism. Such errors are attributed to pathogenic gene variants causing phenylalanine hydroxylase (PAH) deficiency, impairing the hydroxylation of phenylalanine to tyrosine in the Phe metabolic pathway. This defect leads to plasma Phe concentrations above the normal range. If untreated, hyperphenylalaninemia can adversely affect brain function, leading to severe intellectual disability and seizures. Since 1969, the newborn dried blood spot test has remained the main method of early screening and diagnosis for PKU. The primary therapeutic management is a lifelong phenylalanine-restricted diet with the aim of decreasing plasma Phe levels. The recommended diet consists of avoiding high-protein foods such as meat, fish, eggs and nuts, and can be supplemented with high-protein medical formulas which are low in phenylalanine. Pharmacological interventions such as sapropterin, sepiapterin and pegvaliase can also be used as treatment adjuncts in patients with PKU. Currently, small-molecule inhibitors reducing renal phenylalanine reabsorption are being explored as a potential therapeutic intervention. Furthermore, novel gene-editing techniques are under evaluation as potential curative strategies, with preclinical studies showing promising results in correcting pathogenic phenylalanine hydroxylase variants. This non-systematic review synthesises current literature on the management of PKU, with a focus on dietary interventions and recommendations. Full article
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15 pages, 2483 KB  
Perspective
Personalized Medicine, Storied Past, Contentious Present, Promising Future
by Kenneth P. H. Pritzker and Arash Samari
J. Pers. Med. 2026, 16(4), 217; https://doi.org/10.3390/jpm16040217 - 16 Apr 2026
Viewed by 603
Abstract
Personalized Medicine has been a central aspiration of medical practice and has guided the direction of medical advances from ancient times to the present. This narrative review highlights some of the most significant past advances and present practices, discusses issues currently limiting Personalized [...] Read more.
Personalized Medicine has been a central aspiration of medical practice and has guided the direction of medical advances from ancient times to the present. This narrative review highlights some of the most significant past advances and present practices, discusses issues currently limiting Personalized Medicine and proposes activities necessary for Personalized Medicine to have a promising future. Throughout history, Personalized Medicine has developed along with the evolution of science and societal concepts. Notable advances paralleled the growth in what an individual person is and how experimental science can apply to medical practice. In the twentieth century, the study of inborn errors of metabolism and pharmacogenetics broadened the horizons of what Personalized Medicine could be. Presently, Personalized Medicine is challenged by different perspectives on its scope, by the various clinical scientific activities which can inadvertently or by misinterpretation serve to depersonalize medicine, and by the difficulties involved in integrating the massive amount of available scientific data to optimize medical practice centered on the individual. The conditions necessary for Personalized Medicine to have a promising future include developing broader, deeper, and more dynamic knowledge of disease processes, new methods to identify anomalous, singular disease-contributing characteristics in individuals, and improving data quality in research and medical practice. Advancing Personalized Medicine requires developing new perspectives for research, healthcare education, medical practice, and healthcare governance, as well as deploying medical advances at scale across populations. Full article
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12 pages, 813 KB  
Article
Implementing Genetic Counseling for Rare Diseases in LMICs: Pediatric and Prenatal Perspectives from India
by Siddannagoud, Dolat Singh Shekhawat, Kuldeep Singh, Varuna Vyas, Pratibha Singh, Charu Sharma, Navdeep Kaur Ghuman and Tanu Gupta
Thalass. Rep. 2026, 16(2), 6; https://doi.org/10.3390/thalassrep16020006 - 1 Apr 2026
Viewed by 438
Abstract
Background: This study investigated the clinical characteristics of consultands and examined their perceived personal control, satisfaction, and decision-making regarding genetic testing, as well as the factors influencing these outcomes, at a tertiary care center in northwestern India. Methods: Detailed clinical and family histories [...] Read more.
Background: This study investigated the clinical characteristics of consultands and examined their perceived personal control, satisfaction, and decision-making regarding genetic testing, as well as the factors influencing these outcomes, at a tertiary care center in northwestern India. Methods: Detailed clinical and family histories were recorded, and trained genetic professionals provided genetic counseling. Perceived personal control (PPC) was assessed pre- and post-counseling using the PPC (nine-item) questionnaire, while post-counseling satisfaction was measured using the six-item Genetic Counseling Satisfaction Scale (GCSS). Outcomes included awareness of genetic disorders, uptake of genetic testing, and reproductive decision-making. Results: A total of 225 consultands (125 pediatric and 100 antenatal) were enrolled. The most common systemic disorders were: inborn errors of metabolism (21.3%), congenital anomalies (15.2%), neurological disorders (15%), primary immunodeficiencies (12.3%), renal genetic disorders (12.2%), respiratory disorders (12%), thalassemia (9%), endocrine disorders (3.9%), and cardiovascular anomalies (3%). In the pediatric group, socioeconomic status (p = 0.048) and higher education levels (p = 0.02) were significantly associated with higher perceptions of adequate counseling time and overall GCSS. None of the examined factors in the prenatal group showed a statistically significant association with satisfaction scores. Consultands primarily concerned with preventing recurrence in future pregnancies showed significantly higher PPC scores both before (p = 0.026) and after counseling (p = 0.009), with the greatest overall improvement in satisfaction (p = 0.044). In the pediatric group, those with an affected family member showed the greatest post-counseling improvement in PPC. Conclusions: Low education, limited awareness, socioeconomic constraints, delayed presentation and low referral rates were key barriers to effective genetic counseling. Addressing these factors can improve consultand awareness, satisfaction, decision-making, and uptake of genetic testing, thereby enhancing reproductive outcomes in high-risk families. Full article
(This article belongs to the Section Quality of Life)
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20 pages, 1722 KB  
Article
Fully Automated Serum LC-MS/MS Platform and Pediatric Reference Intervals for Organic Acids, Amino Acids, and Acylcarnitines in Children (Ages 0–6 Years): Toward Quantitative Diagnosis of Inborn Errors of Metabolism
by Yasushi Ueyanagi, Daiki Setoyama, Tsuyoshi Nakanishi, Yuichi Mushimoto, Vlad Tocan, Hironori Kobayashi, Miki Matsui, Shinya Matsumoto, Akiyoshi Fujishima, Taeko Hotta, Ayumi Sakata and Yuya Kunisaki
Diagnostics 2026, 16(6), 911; https://doi.org/10.3390/diagnostics16060911 - 19 Mar 2026
Viewed by 845
Abstract
Background/Objectives: Conventional diagnosis of inborn errors of metabolism (IEMs) requires multiple specimen types—urine organic acids, plasma amino acids, and serum acylcarnitines—analyzed on distinct analytical platforms. This multi-assay approach is labor-intensive and limits timely clinical decision making. We aimed to develop a fully automated [...] Read more.
Background/Objectives: Conventional diagnosis of inborn errors of metabolism (IEMs) requires multiple specimen types—urine organic acids, plasma amino acids, and serum acylcarnitines—analyzed on distinct analytical platforms. This multi-assay approach is labor-intensive and limits timely clinical decision making. We aimed to develop a fully automated serum-based LC–MS/MS platform for integrated quantitative metabolite profiling and to establish pediatric reference intervals (RIs) to support diagnostic interpretation. Methods: A fully automated LC–MS/MS system integrated with the CLAM-2030 automated pretreatment module was developed to enable simultaneous quantification of 25 organic acids, 8 amino acids, and 21 acylcarnitines. Analytical performance was assessed for linearity, limits of detection and quantification, precision and accuracy. Serum samples from 296 non-IEM children aged 0–6 years were analyzed to establish pediatric RIs using Box–Cox transformation and Gaussian modeling. Clinical utility was evaluated in sera from 89 patients diagnosed with IEM using z-score-based logistic regression models. Results: The method demonstrated excellent performance, with linearity (r2 > 0.99) across calibration ranges, limits of detection and quantification defined by signal-to-noise ratios > 3 and >10, and intra- and inter-assay precision < 15% CV for all 54 analytes. Twenty-one analytes met the acceptance criterion of ±20% accuracy at all quality-control levels. Pediatric RIs provided a quantitative framework for interpreting the metabolic abnormalities. In IEM patients, disease-specific metabolites were consistently outside the established ranges, and z-score-based logistic regression models successfully distinguished major IEM categories, including organic acidemias and long-chain fatty acid oxidation disorders. Conclusions: This fully automated, serum-based LC–MS/MS platform provides a clinically practical and quantitative framework for integrated metabolic profiling using pediatric RIs, supporting diagnosis and monitoring of IEMs in pediatric settings. Full article
(This article belongs to the Section Clinical Laboratory Medicine)
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25 pages, 4322 KB  
Review
Pyruvate Dehydrogenase Complex Deficiency: A Review of Treatments and Case Series
by Batya Betesh-Abay, Eilon Shany, Orna Staretz-Chacham, Ilan Shelef and Abed N. Azab
Int. J. Mol. Sci. 2026, 27(6), 2732; https://doi.org/10.3390/ijms27062732 - 17 Mar 2026
Viewed by 1950
Abstract
Pyruvate dehydrogenase complex deficiency (PDCD) is a heterogenous mitochondrial inborn error in carbohydrate oxidation manifesting as congenital lactic acidosis. PDCD presents diagnostic and therapeutic challenges. While no curative treatment exists for PDCD, certain therapeutic modalities may improve prognosis and ameliorate symptom severity. This [...] Read more.
Pyruvate dehydrogenase complex deficiency (PDCD) is a heterogenous mitochondrial inborn error in carbohydrate oxidation manifesting as congenital lactic acidosis. PDCD presents diagnostic and therapeutic challenges. While no curative treatment exists for PDCD, certain therapeutic modalities may improve prognosis and ameliorate symptom severity. This article examines the effectiveness of treatments for PDCD and presents a case series of three patients with PDCD. A scoping literature review was conducted for treatments of PDCD. Patient data for case reports was extracted retrospectively from electronic medical records from a large tertiary hospital. We reviewed and summarized findings from seven preclinical studies and ten human studies, which showed that dichloroacetate and the ketogenic diet were the most frequently studied treatments. Therapeutic approaches observed select positive outcomes such as reduced lactate levels, improved neuropathological manifestations, and increased longevity. However, most interventions have yet to be rigorously investigated. Early diagnosis of PDCD is integral, as treatment methods may offer improved clinical and biochemical outcomes. Clinical trials of existing and novel treatments are necessary to improve management and further understand the prognostic potential of this metabolic disorder. Full article
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17 pages, 2148 KB  
Article
Clinical and Genetic Characterization of Isolated Methylmalonic Acidemia in Malaysian Children: Identification of Two Novel MMUT Variants
by Mardhiah Masri, Norzahidah Khalid, Noornatisha Salleh, Seok-Hian Lua, Nor Azimah Abdul Azize, Yusnita Yakob, Ernie Zuraida Ali, Vani A/P Munusamy, Lock-Hock Ngu, Jeffrey Soon-Yit Lee, Teck-Hock Toh and Anasufiza Habib
Diagnostics 2026, 16(5), 755; https://doi.org/10.3390/diagnostics16050755 - 3 Mar 2026
Viewed by 567
Abstract
Background/Objectives: Isolated methylmalonic acidemia (iMMA) is a rare autosomal recessive metabolic disorder caused by defects in methylmalonyl-CoA mutase (MCM) activity or in the biosynthesis of its cofactor, adenosylcobalamin. Mutations in five genes—MMUT, MMAA, MMAB, MMADHC, and MCEE [...] Read more.
Background/Objectives: Isolated methylmalonic acidemia (iMMA) is a rare autosomal recessive metabolic disorder caused by defects in methylmalonyl-CoA mutase (MCM) activity or in the biosynthesis of its cofactor, adenosylcobalamin. Mutations in five genes—MMUT, MMAA, MMAB, MMADHC, and MCEE—are known to underlie this condition. This study aimed to characterize the clinical features and molecular spectrum of iMMA in Malaysian patients of diverse ethnic backgrounds. Material and Methods: Patients with biochemical evidence suggestive of iMMA, including elevated propionylcarnitine (C3), increased C3/C2 ratio, and raised urine methylmalonic acid levels in the absence of hyperhomocysteinemia, were selected for genetic testing. Sanger sequencing was performed to identify pathogenic variants in the MMUT, MMAA, MMAB, MMADHC, or MCEE genes. Results: The cohort consisted predominantly of Iban patients (n = 5), with the remaining cases comprising one Malay and one Thai–Malay individual. Age at diagnosis ranged from Day 1 of life to 6 years. All 7 patients were confirmed to have iMMA through molecular analysis. A total of seven pathogenic or likely pathogenic variants were identified, including two novel MMUT variants (c.246_250delinsGA and c.1358G>C), four known MMUT variants (c.560C>G, c.693C>G, c.982C>T, c.1106G>A), and one known MMAB variant (c.644+1G>A). Clinical presentation and disease severity varied across cases, reflecting underlying genotypic heterogeneity. Conclusions: This study highlights the molecular diversity and clinical variability of iMMA in Malaysia. Our findings reinforce the importance of integrating metabolic screening with molecular diagnostics to identify disease-causing variants and guide patient management strategies effectively. Full article
(This article belongs to the Section Pathology and Molecular Diagnostics)
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13 pages, 578 KB  
Article
The Impact of Nutritional Management on Fat-Soluble Nutrient Status in Patients with Fatty Acid Oxidation Disorders: A Cross-Sectional Study
by Maria Wasiewicz-Gajdzis, Małgorzata Jamka, Łukasz Kałużny, Natalia Wichłacz-Trojanowska, Anna Blask-Osipa, Monika Duś-Żuchowska, Joanna Jagłowska, Szymon Kurek, Anna Miśkiewicz-Chotnicka and Jarosław Walkowiak
Metabolites 2026, 16(2), 124; https://doi.org/10.3390/metabo16020124 - 11 Feb 2026
Viewed by 821
Abstract
Background: Fatty acid oxidation disorders (FAOD) are rare inborn errors of metabolism that impair mitochondrial β-oxidation and energy production. Management includes fasting avoidance for all FAOD types. Patients with long-chain FAOD are advised to restrict long-chain triglycerides (LCTs) to 10% of total energy [...] Read more.
Background: Fatty acid oxidation disorders (FAOD) are rare inborn errors of metabolism that impair mitochondrial β-oxidation and energy production. Management includes fasting avoidance for all FAOD types. Patients with long-chain FAOD are advised to restrict long-chain triglycerides (LCTs) to 10% of total energy intake and supplement medium-chain triglycerides (MCTs). The impact of such dietary modification on fat-soluble vitamin status has not yet been studied. Methods: In this cross-sectional study, serum concentrations of vitamins A, 25(OH)D, E, and β-carotene were measured in 36 FAOD patients and 36 healthy controls matched for age and sex. Vitamins A, E, and β-carotene were quantified using high-performance liquid chromatography and vitamin 25(OH)D through an immunoassay. FAOD patients were further divided into fat-modified (LCT-restricted) and standard-fat diet subgroups based on dietary management. Results: FAOD patients had significantly higher vitamin A concentrations than controls (p < 0.05), while there was no difference in vitamins 25(OH)D, E, and β-carotene. Within the FAOD cohort, the fat-modified group had higher levels of vitamins A and 25(OH)D but lower levels of vitamin E and β-carotene than the standard-fat group (all p < 0.05). Vitamin 25(OH)D deficiency (<20 ng/mL) was more frequent in the standard-fat group (p = 0.03). Conclusions: Fat-modified diets influence fat-soluble vitamin status in FAOD, emphasising the importance of ongoing monitoring and tailored supplementation. Future work should focus on optimising nutritional management, including modifications to formula composition, and on addressing the currently limited evidence on nutritional status and vitamin deficiencies in patients with FAOD. Full article
(This article belongs to the Section Nutrition and Metabolism)
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7 pages, 587 KB  
Case Report
Genotype-Phenotype Delineation of Autoimmune Polyendocrinopathy, Candidiasis, and Ectodermal Dystrophy in a Pediatric Patient: A Case Report
by Rima Hanna-Wakim, Pascale E. Karam, Mazen Kurban and Nadine Yazbeck
Genes 2026, 17(2), 160; https://doi.org/10.3390/genes17020160 - 29 Jan 2026
Viewed by 622
Abstract
Background/Objectives: Autoimmune Polyendocrinopathy with Candidiasis and Ectodermal Dystrophy is an extremely rare autosomal recessive disorder caused by inborn errors of immunity. It is due to a loss-of-function mutation in the AIRE autoimmune regulator gene. Its manifestations include autoimmunity affecting endocrine glands, in addition [...] Read more.
Background/Objectives: Autoimmune Polyendocrinopathy with Candidiasis and Ectodermal Dystrophy is an extremely rare autosomal recessive disorder caused by inborn errors of immunity. It is due to a loss-of-function mutation in the AIRE autoimmune regulator gene. Its manifestations include autoimmunity affecting endocrine glands, in addition to non-endocrine manifestations including dental enamel hypoplasia, alopecia areata, hepatitis, and chronic mucocutaneous candidiasis. Globally, 10 cases per million are affected by this condition, with higher incidence in highly consanguineous populations. Here, we describe a novel AIRE gene mutation in a pediatric patient from Lebanon, along with the observed phenotype. Method: A nine-year-old boy with history of craniosynostosis presented with jaundice. His past medical history was significant for recurrent oral thrush, keratoconjunctivitis, nail dystrophy, and alopecia. Upon presentation, he had jaundice, isolated splenomegaly, and severe failure to thrive. Laboratory tests showed transaminitis, cholestasis, and hypergammaglobulinemia. Abdominal ultrasound findings were suggestive of cirrhosis with compensated portal hypertension. The differential diagnosis included viral infection, inborn errors of metabolism, and autoimmune hepatitis. Results: Exome sequencing identified a novel homozygous pathogenic variant in the AIRE gene, NM_000383.4: c.1066dup p.(Arg356Profs*16), confirming the diagnosis. Conclusions: This study expands the genotypic and phenotypic spectrum of a rare inborn error of immunity in a child with chronic mucocutaneous candidiasis, enamel hypoplasia, and hepatitis. Full article
(This article belongs to the Section Human Genomics and Genetic Diseases)
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26 pages, 769 KB  
Systematic Review
Myoclonus in Pediatric Metabolic Diseases: Clinical Spectrum, Mechanisms, and Treatable Causes—A Systematic Review
by Elżbieta Majewska, Zofia Zdort, Aleksandra Ochocka and Justyna Paprocka
Metabolites 2026, 16(2), 98; https://doi.org/10.3390/metabo16020098 - 28 Jan 2026
Viewed by 1020
Abstract
Background: Myoclonus, a sudden brief shock-like involuntary movement, represents a common yet under-recognized manifestation across many inherited metabolic disorders. Although its occurrence has been reported in case series and small cohorts, the overall spectrum, pathophysiological mechanisms, and therapeutic relevance of metabolic myoclonus [...] Read more.
Background: Myoclonus, a sudden brief shock-like involuntary movement, represents a common yet under-recognized manifestation across many inherited metabolic disorders. Although its occurrence has been reported in case series and small cohorts, the overall spectrum, pathophysiological mechanisms, and therapeutic relevance of metabolic myoclonus have not been systematically summarized. Methods: A systematic search of PubMed was conducted for English-language publications from 2014 to 2025 using predefined MeSH terms related to myoclonus, movement disorders, and inborn errors of metabolism. Titles and abstracts were screened independently by three reviewers. After removal of duplicates, 27 articles were included, complemented by 65 additional references addressing individual disorders. Data were organized according to the International Classification of Inherited Metabolic Disorders (ICIMD). Results: Myoclonus was documented across six ICIMD categories, including intermediary metabolism, mitochondrial energy metabolism, lipid metabolism, disorders of complex molecules and organelles, cofactor and mineral metabolism, and metabolic cell signaling disorders. Clinical presentation ranged from isolated jerks to progressive myoclonic epilepsies. Several conditions—such as GLUT1 deficiency, cerebrotendinous xanthomatosis, and folate receptor α deficiency—are treatable through dietary or pharmacological interventions. Conclusions: Recognition of myoclonus as a presenting feature of inherited errors of metabolism (IEMs) is critical for timely diagnosis and treatment. Metabolic screening should be considered in all unexplained cases of myoclonus, particularly when accompanied by developmental delay or systemic abnormalities. Full article
(This article belongs to the Section Cell Metabolism)
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9 pages, 709 KB  
Communication
Towards Next-Generation Sequencing as a First-Tier Diagnostic Test for Fructose-1,6-Bisphosphatase Deficiency
by Nadine Yazbeck, Abir Barhoumi and Pascale E. Karam
Metabolites 2026, 16(1), 56; https://doi.org/10.3390/metabo16010056 - 8 Jan 2026
Viewed by 555
Abstract
Background: Advances in genomic technologies combined with tandem mass newborn screening have enabled early detection and management of several common inborn errors of metabolism. Fructose-1,6-bisphosphatase deficiency, an autosomal recessive treatable disorder reported in around 150 patients worldwide, remains underdiagnosed despite an excellent prognosis [...] Read more.
Background: Advances in genomic technologies combined with tandem mass newborn screening have enabled early detection and management of several common inborn errors of metabolism. Fructose-1,6-bisphosphatase deficiency, an autosomal recessive treatable disorder reported in around 150 patients worldwide, remains underdiagnosed despite an excellent prognosis with early detection. Although common in highly consanguineous populations, diagnosis is often delayed due to the non-specific clinical and biochemical profile. Methods: This report explores the diagnostic pathway using first-tier next-generation sequencing of three novel cases of fructose-1,6-bisphosphatase deficiency in a tertiary care center in Lebanon. Results: Two patients were diagnosed with first-tier exome sequencing within one month of presentation and had an excellent outcome at 6 years of follow-up. The third patient, undiagnosed for 10 years, suffered from neurological sequalae. The molecular profile was remarkable in two patients for exon 2 deletion in the FBP1 gene, a founder mutation reported in Turkish and Armenian patients, and a rare frameshift mutation in the third case. Conclusions: The use of next-generation sequencing as as a first-tier test for FBP deficiency is a non-invasive and rapid method for early diagnosis and management of this rare yet treatable disorder. It can detect both disease-causing variants and large deletions, founder mutations as well, delineating the molecular profile in populations where this disorder is highly prevalent. Full article
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19 pages, 628 KB  
Article
Modelling the Transference of Paediatric Patients with Inborn Errors of Metabolism to Adult Hospitals: Clinical Experience
by Aida Deudero, Esther Lasheras, Roser Ventura, Cristina Montserrat-Carbonell, José César Milisenda, Natalia Juliá-Palacios, Ana Matas, María de Talló Forga-Visa, Rosa María López-Galera, Judit García-Villoria, Mercè Placeres, Adriana Pané, Glòria Garrabou, Antonia Ribes, Francesc Cardellach, Pedro Juan Moreno-Lozano, Àngels Garcia-Cazorla, Jaume Campistol and IEM-SJD-HCB Consortia
J. Clin. Med. 2026, 15(1), 81; https://doi.org/10.3390/jcm15010081 - 22 Dec 2025
Viewed by 848
Abstract
Background/Objectives: Inborn errors of metabolism (IEM) are chronic, life-threatening genetic disorders with a significant cumulative prevalence worldwide. Advances in early diagnosis and treatment have significantly increased life expectancy, underscoring the need for specialised adult care units and the establishment of structured transition [...] Read more.
Background/Objectives: Inborn errors of metabolism (IEM) are chronic, life-threatening genetic disorders with a significant cumulative prevalence worldwide. Advances in early diagnosis and treatment have significantly increased life expectancy, underscoring the need for specialised adult care units and the establishment of structured transition programmes from paediatric to adult services. We hereby present a functional transition model for IEM patients and share our implementation experience. Methods: Initiated in 2012, the partnership between the paediatric Hospital Sant Joan de Déu (HSJD) and the adult-care centre at Hospital Clinic of Barcelona (HCB) culminated in 2019 with the transference of the first IEM patients under the structured A10! Programme. This model is structured around the transition units of paediatric and adult centres to guarantee communication and functional management. Regular monthly meetings at each centre and joint quarterly sessions allowed for protocol harmonisation and personalised care planning. Coordinated engagement of the multidisciplinary health care teams with patients and families smoothed the transfer process. Results: Between 2019 and 2024, 94 IEM patients were successfully transferred. Diagnoses included intermediary metabolism defects (71.23%), lipid metabolism and transport disorders (4.25%), heterocyclic compound metabolism (2.12%), complex molecules and organelle dysfunction (6.37%), cofactor and mineral metabolism (2.12%), signalling defects (5.31%), and unclassified cases (8.51% of rare disorders, maybe non-IEM). Transition formats included 21 in-person joint visits in HSJD, 37 remote transitions during the COVID-19 pandemic, and 36 streamlined transfers via standardised protocols. Sessions, trainings, and meetings allowed the exchange of patients’ needs and protocols. Conclusions: The successful transference of IEM patients requires structured programmes with interdisciplinary paediatric and adult teams, joining efforts with the patient, families, and caregivers. Communication between paediatric and adult transition units is essential to promote continuity of care and patient empowerment. While constantly updated, this model has proven effective, gaining positive evaluations from healthcare professionals and patients alike, representing a scalable framework for lifelong management of IEM in adult care settings. Full article
(This article belongs to the Section Clinical Guidelines)
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32 pages, 2543 KB  
Article
Vitamins D, A and E, and Beta-Carotene in Adherent and Non-Adherent Individuals with Phenylketonuria: Cross-Sectional Study, Systematic Review and Meta-Analysis
by Kamila Bokayeva, Małgorzata Jamka, Łukasz Kałużny, Monika Duś-Żuchowska, Natalia Wichłacz-Trojanowska, Renata Mozrzymas, Agnieszka Chrobot, Dariusz Walkowiak, Olga Ļubina, Ilya Rabkevich, Szymon Kurek, Anna Miśkiewicz-Chotnicka, Gulnara Sultanova, Karl-Heinz Herzig, Madara Auzenbaha and Jarosław Walkowiak
Nutrients 2025, 17(24), 3932; https://doi.org/10.3390/nu17243932 - 16 Dec 2025
Viewed by 1151
Abstract
Background/Objectives: The impact of dietary adherence and formula intake regularity on fat-soluble vitamin status in phenylketonuria (PKU) is uncertain. This study assessed whether vitamin A, D, E, and beta-carotene levels differ by dietary adherence and regularity of Phe-free formula intake. Methods: A cross-sectional [...] Read more.
Background/Objectives: The impact of dietary adherence and formula intake regularity on fat-soluble vitamin status in phenylketonuria (PKU) is uncertain. This study assessed whether vitamin A, D, E, and beta-carotene levels differ by dietary adherence and regularity of Phe-free formula intake. Methods: A cross-sectional study included 98 individuals (age 6–41 years) with vitamin D measurements. In a subgroup of 68 patients, vitamin A, vitamin E, and beta-carotene levels were determined. Vitamin levels were compared between adherent and non-adherent groups and between participants with regular vs. irregular formula intake. A subsequent systematic review and meta-analysis of six studies (from PubMed, Scopus, Web of Science, and Cochrane; searched in August 2025) pooled standardised mean differences (SMDs) using fixed-effects and random-effects models. Results: The cross-sectional results showed higher vitamin D in adherent (35.60 [30.39–41.65] vs. 32.90 [26.50–40.00] ng/mL, p = 0.034) and regular formula consumers (35.97 [30.03–42.28] vs. 30.20 [26.08–35.06] ng/mL, p = 0.002). Beta-carotene was elevated with regular intake (74.40 [56.70–98.45] vs. 53.20 [34.10–68.60] ng/mL, p = 0.003). Meta-analysis confirmed higher vitamin D in adherent individuals (fixed-effects model, SMD = 0.290, 95% CI: 0.004, 0.576, p = 0.047) and regular consumers (fixed-effects model, SMD = 0.750, 95% CI: 0.382, 1.118, p < 0.0001). No differences were observed for vitamin E or beta-carotene. Conclusions: Adherence to diet and regular formula intake is associated with improved vitamin D status, underscoring the critical role of fortified formulas in PKU management. The very low certainty of evidence necessitates further research, especially for the other fat-soluble vitamins. Nonetheless, clinical practice should emphasise support for adherence and ongoing nutritional monitoring. Full article
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38 pages, 1041 KB  
Review
Inborn Errors of Amino Acid Metabolism Revisited: Clinical Implications and Insights into Current Therapies
by Abdul L. Shakerdi, Darragh Nerney, Eleanor J. Molloy and Ina Knerr
J. Clin. Med. 2025, 14(24), 8749; https://doi.org/10.3390/jcm14248749 - 10 Dec 2025
Viewed by 4081
Abstract
Background/Objectives: Inborn errors of amino acid metabolism (IEAAMs) are inherited disorders caused by defects in amino acid catabolism, biosynthesis, or transport. In this review, we aimed to synthesise recent evidence on the clinical manifestations and current and future therapeutic strategies for major IEAAMs. [...] Read more.
Background/Objectives: Inborn errors of amino acid metabolism (IEAAMs) are inherited disorders caused by defects in amino acid catabolism, biosynthesis, or transport. In this review, we aimed to synthesise recent evidence on the clinical manifestations and current and future therapeutic strategies for major IEAAMs. Methods: A narrative review was undertaken on studies published up to November 2025. No fixed start date was set. Instead, earlier studies were included if historically significant or frequently cited in contemporary guidelines, and emphasis was placed on recent developments over the last 5–10 years. Evidence was identified through structured searches of PubMed, clinical trial registries, and public communications on selected IEAAMs, which were synthesised in textual and tabular form. Results: Management across IEAAMs involves the restriction of amino acids or natural proteins, disease-specific dietary formulations, micronutrient optimisation, cofactor or enzyme replacement, and pharmacological chaperones. This is supported by structured monitoring and emergency regimens to prevent catabolic crises. Organ transplantation remains crucial for select indications, such as liver transplantation in hereditary tyrosinaemia with liver disease. Novel approaches include substrate reduction, the pharmacological targeting of upstream pathways, viral vector gene transfer, and liver-directed mRNA therapy. Several of these novel approaches have entered clinical trials, but many remain in the preclinical stage. Conclusions: Despite advances in the treatment of IEAAMs, many patients still experience significant morbidity. Future focus should be on further refining emerging molecular and gene-based treatments and optimising neuroprotective and metabolic targets. The equitable implementation of personalised, life-spanning treatments within multidisciplinary rare disease services will be essential. Full article
(This article belongs to the Section Clinical Pediatrics)
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