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Drackley A, Peter M, Rathbun P, Ing A, Prada CE, Yap KL. Homozygosity for disease-causing variants in AMT and GLDC in a patient with severe nonketotic hyperglycinemia. Am J Med Genet A 2024; 194:e63622. [PMID: 38572626 DOI: 10.1002/ajmg.a.63622] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2023] [Revised: 03/07/2024] [Accepted: 03/25/2024] [Indexed: 04/05/2024]
Abstract
Nonketotic hyperglycinemia (NKH) is a relatively well-characterized inborn error of metabolism that results in a combination of lethargy, hypotonia, seizures, developmental arrest, and, in severe cases, death early in life. Three genes encoding components of the glycine cleavage enzyme system-GLDC, AMT, and GCSH-are independently associated with NKH. We report on a patient with severe NKH in whom the homozygous pathogenic variant in AMT (NM_000481.3):c.602_603del (p.Lys201Thrfs*75) and the homozygous likely pathogenic variant in GLDC(NM_000170.2):c.2852C>A (p.Ser951Tyr) were both identified. Our patient demonstrates a novel combination of two homozygous disease-causing variants impacting the glycine cleavage pathway at two different components, and elicits management- and genetic counseling-related challenges for the family.
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Affiliation(s)
- Andy Drackley
- Department of Pathology & Laboratory Medicine, Ann & Robert H. Lurie Children's Hospital of Chicago, Chicago, Illinois, USA
- Division of Genetics, Genomics, and Metabolism, Ann & Robert H. Lurie Children's Hospital of Chicago, Chicago, Illinois, USA
| | - Merlene Peter
- Division of Genetics, Genomics, and Metabolism, Ann & Robert H. Lurie Children's Hospital of Chicago, Chicago, Illinois, USA
| | - Pamela Rathbun
- Department of Pathology & Laboratory Medicine, Ann & Robert H. Lurie Children's Hospital of Chicago, Chicago, Illinois, USA
- Department of Pathology, Northwestern University Feinberg School of Medicine, Chicago, Illinois, USA
| | - Alexander Ing
- Department of Pathology & Laboratory Medicine, Ann & Robert H. Lurie Children's Hospital of Chicago, Chicago, Illinois, USA
- Division of Genetics, Genomics, and Metabolism, Ann & Robert H. Lurie Children's Hospital of Chicago, Chicago, Illinois, USA
- Department of Pediatrics, Northwestern University Feinberg School of Medicine, Chicago, Illinois, USA
| | - Carlos E Prada
- Division of Genetics, Genomics, and Metabolism, Ann & Robert H. Lurie Children's Hospital of Chicago, Chicago, Illinois, USA
- Department of Pediatrics, Northwestern University Feinberg School of Medicine, Chicago, Illinois, USA
| | - Kai Lee Yap
- Department of Pathology & Laboratory Medicine, Ann & Robert H. Lurie Children's Hospital of Chicago, Chicago, Illinois, USA
- Department of Pathology, Northwestern University Feinberg School of Medicine, Chicago, Illinois, USA
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2
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Leipnitz G, da Rosa JS, Wajner M. The Role of Excitotoxicity, Oxidative Stress and Bioenergetics Disruption in the Neuropathology of Nonketotic Hyperglycinemia. Neurotox Res 2024; 42:32. [PMID: 38949693 DOI: 10.1007/s12640-024-00711-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2024] [Revised: 06/11/2024] [Accepted: 06/20/2024] [Indexed: 07/02/2024]
Abstract
Nonketotic hyperglycinemia (NKH) is an inherited disorder of amino acid metabolism biochemically characterized by the accumulation of glycine (Gly) predominantly in the brain. Affected patients usually manifest with neurological symptoms including hypotonia, seizures, epilepsy, lethargy, and coma, the pathophysiology of which is still not completely understood. Treatment is limited and based on lowering Gly levels aiming to reduce overstimulation of N-methyl-D-aspartate (NMDA) receptors. Mounting in vitro and in vivo animal and human evidence have recently suggested that excitotoxicity, oxidative stress, and bioenergetics disruption induced by Gly are relevant mechanisms involved in the neuropathology of NKH. This brief review gives emphasis to the deleterious effects of Gly in the brain of patients and animal models of NKH that may offer perspectives for the development of novel adjuvant treatments for this disorder.
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Affiliation(s)
- Guilhian Leipnitz
- Programa de Pós-Graduação em Ciências Biológicas: Bioquímica, Universidade Federal do Rio Grande do Sul, Rua Ramiro Barcelos, 2600-Anexo, Porto Alegre, RS, 90035-003, Brazil.
- Programa de Pós-Graduação em Ciências Biológicas: Fisiologia, Universidade Federal do Rio Grande do Sul, Rua Ramiro Barcelos, 2600-Anexo, Porto Alegre, RS, CEP 90035-003, Brazil.
| | - Jaqueline Santana da Rosa
- Programa de Pós-Graduação em Ciências Biológicas: Bioquímica, Universidade Federal do Rio Grande do Sul, Rua Ramiro Barcelos, 2600-Anexo, Porto Alegre, RS, 90035-003, Brazil
| | - Moacir Wajner
- Programa de Pós-Graduação em Ciências Biológicas: Bioquímica, Universidade Federal do Rio Grande do Sul, Rua Ramiro Barcelos, 2600-Anexo, Porto Alegre, RS, 90035-003, Brazil
- Programa de Pós-Graduação em Ciências Biológicas: Fisiologia, Universidade Federal do Rio Grande do Sul, Rua Ramiro Barcelos, 2600-Anexo, Porto Alegre, RS, CEP 90035-003, Brazil
- Serviço de Genética Médica, Hospital de Clínicas de Porto Alegre, Rua Ramiro Barcelos, 2350, Porto Alegre, 90035-903, RS, Brazil
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3
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Swanson MA, Jiang H, Busquet N, Carlsen J, Brindley C, Benke TA, Van Hove RA, Friederich MW, MacLean KN, Mesches MH, Van Hove JLK. Deep postnatal phenotyping of a new mouse model of nonketotic hyperglycinemia. J Inherit Metab Dis 2024. [PMID: 38840294 DOI: 10.1002/jimd.12755] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/17/2023] [Revised: 04/18/2024] [Accepted: 05/02/2024] [Indexed: 06/07/2024]
Abstract
Nonketotic hyperglycinemia due to deficient glycine cleavage enzyme activity causes a severe neonatal epileptic encephalopathy. Current therapies based on mitigating glycine excess have only limited impact. An animal model with postnatal phenotyping is needed to explore new therapeutic approaches. We developed a Gldc p.Ala394Val mutant model and bred it to congenic status in two colonies on C57Bl/6J (B6) and J129X1/SvJ (J129) backgrounds. Mutant mice had reduced P-protein and enzyme activity indicating a hypomorphic mutant. Glycine levels were increased in blood and brain regions, exacerbated by dietary glycine, with higher levels in female than male J129 mice. Birth defects were more prevalent in mutant B6 than J129 mice, and hydrocephalus was more frequent in B6 (40%) compared to J129 (none). The hydrocephalus rate was increased by postnatal glycine challenge in B6 mice, more so when delivered from the first neonatal week than from the fourth. Mutant mice had reduced weight gain following weaning until the eighth postnatal week, which was exacerbated by glycine loading. The electrographic spike rate was increased in mutant mice following glycine loading, but no seizures were observed. The alpha/delta band intensity ratio was decreased in the left cortex in female J129 mice, which were less active in an open field test and explored less in a Y-maze, suggesting an encephalopathic effect. Mutant mice showed no evidence of memory dysfunction. This partial recapitulation of human symptoms and biochemistry will facilitate the evaluation of new therapeutic approaches with an early postnatal time window likely most effective.
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Affiliation(s)
- Michael A Swanson
- Department of Pediatrics, Section of Clinical Genetics and Metabolism, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
| | - Hua Jiang
- Department of Pediatrics, Section of Clinical Genetics and Metabolism, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
| | - Nicolas Busquet
- NeuroTechnology Center, School of Medicine, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
- Department of Neurology, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
| | - Jessica Carlsen
- NeuroTechnology Center, School of Medicine, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
| | - Connie Brindley
- NeuroTechnology Center, School of Medicine, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
| | - Tim A Benke
- Department of Pediatrics, Section of Pediatric Neurology, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
| | - Roxanne A Van Hove
- Department of Pediatrics, Section of Clinical Genetics and Metabolism, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
| | - Marisa W Friederich
- Department of Pediatrics, Section of Clinical Genetics and Metabolism, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
| | - Kenneth N MacLean
- Department of Pediatrics, Section of Clinical Genetics and Metabolism, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
| | - Michael H Mesches
- NeuroTechnology Center, School of Medicine, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
- Department of Pediatrics, Section of Pediatric Neurology, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
| | - Johan L K Van Hove
- Department of Pediatrics, Section of Clinical Genetics and Metabolism, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
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4
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Das S, Pal S, Zamal A, Saha AK. A Case of Neonatal Encephalopathy. Neoreviews 2024; 25:e290-e294. [PMID: 38688892 DOI: 10.1542/neo.25-5-e290] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/02/2024]
Affiliation(s)
- Sreetama Das
- Department of Neonatology, IPGME&R, Kolkata, West Bengal, India
| | - Somnath Pal
- Department of Neonatology, IPGME&R, Kolkata, West Bengal, India
| | - Ashadur Zamal
- Department of Neonatology, IPGME&R, Kolkata, West Bengal, India
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5
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Parmeggiani B, Signori MF, Cecatto C, Frusciante MR, Marcuzzo MB, Souza DG, Ribeiro RT, Seminotti B, Gomes de Souza DO, Ribeiro CAJ, Wajner M, Leipnitz G. Glycine disrupts myelin, glutamatergic neurotransmission, and redox homeostasis in a neonatal model for non ketotic hyperglycinemia. Biochimie 2024; 219:21-32. [PMID: 37541567 DOI: 10.1016/j.biochi.2023.07.022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2023] [Revised: 06/26/2023] [Accepted: 07/30/2023] [Indexed: 08/06/2023]
Abstract
Non ketotic hyperglycinemia (NKH) is an inborn error of glycine metabolism caused by mutations in the genes encoding glycine cleavage system proteins. Classic NKH has a neonatal onset, and patients present with severe neurodegeneration. Although glycine accumulation has been implicated in NKH pathophysiology, the exact mechanisms underlying the neurological damage and white matter alterations remain unclear. We investigated the effects of glycine in the brain of neonatal rats and MO3.13 oligodendroglial cells. Glycine decreased myelin basic protein (MBP) and myelin-associated glycoprotein (MAG) in the corpus callosum and striatum of rats on post-natal day (PND) 15. Glycine also reduced neuroglycan 2 (NG2) and N-methyl-d-aspartate receptor subunit 1 (NR1) in the cerebral cortex and striatum on PND15. Moreover, glycine reduced striatal glutamate aspartate transporter 1 (GLAST) content and neuronal nucleus (NeuN), and increased glial fibrillary acidic protein (GFAP) on PND15. Glycine also increased DCFH oxidation and malondialdehyde levels and decreased GSH concentrations in the cerebral cortex and striatum on PND6, but not on PND15. Glycine further reduced viability but did not alter DCFH oxidation and GSH levels in MO3.13 cells after 48- and 72-h incubation. These data indicate that impairment of myelin structure and glutamatergic system and induction of oxidative stress are involved in the neuropathophysiology of NKH.
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Affiliation(s)
- Belisa Parmeggiani
- Programa de Pós-Graduação em Ciências Biológicas - Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil.
| | - Marian Flores Signori
- Programa de Pós-Graduação em Ciências Biológicas - Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil
| | - Cristiane Cecatto
- Programa de Pós-Graduação em Ciências Biológicas - Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil
| | - Marina Rocha Frusciante
- Programa de Pós-Graduação em Ciências Biológicas - Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil
| | - Manuela Bianchin Marcuzzo
- Programa de Pós-Graduação em Ciências Biológicas - Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil
| | - Débora Guerini Souza
- Programa de Pós-Graduação em Ciências Biológicas - Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil; Brain Institute of Rio Grande do Sul, Pontifical Catholic University of Rio Grande do Sul, Porto Alegre, Brazil
| | - Rafael Teixeira Ribeiro
- Programa de Pós-Graduação em Ciências Biológicas - Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil
| | - Bianca Seminotti
- Programa de Pós-Graduação em Ciências Biológicas - Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil
| | - Diogo Onofre Gomes de Souza
- Programa de Pós-Graduação em Ciências Biológicas - Bioquímica, Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil
| | - César Augusto João Ribeiro
- Natural and Humanities Sciences Center, Universidade Federal do ABC, São Bernardo do Campo, SP, 09606-070, Brazil
| | - Moacir Wajner
- Programa de Pós-Graduação em Ciências Biológicas - Bioquímica, Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil; Serviço de Genética Médica do Hospital de Clínicas de Porto Alegre, Porto Alegre, RS, Brazil
| | - Guilhian Leipnitz
- Programa de Pós-Graduação em Ciências Biológicas - Bioquímica, Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil.
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Swanson MA, Jiang H, Busquet N, Carlsen J, Brindley C, Benke TA, Van Hove RA, Friederich MW, MacLean KN, Mesches MH, Van Hove JLK. Deep postnatal phenotyping of a new mouse model of nonketotic hyperglycinemia. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.03.26.586818. [PMID: 38586005 PMCID: PMC10996592 DOI: 10.1101/2024.03.26.586818] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/09/2024]
Abstract
Nonketotic hyperglycinemia due to deficient glycine cleavage enzyme activity causes a severe neonatal epileptic encephalopathy. Current therapies based on mitigating glycine excess have only limited impact. An animal model with postnatal phenotyping is needed to explore new therapeutic approaches. We developed a Gldc p.Ala394Val mutant model and bred it to congenic status in 2 colonies on C57Bl/6J (B6) and J129X1/SvJ (J129) backgrounds. Mutant mice had reduced P-protein and enzyme activity indicating a hypomorphic mutant. Glycine levels were increased in blood and brain regions, exacerbated by dietary glycine, with higher levels in female than male J129 mice. Birth defects were more prevalent in mutant B6 than J129 mice, and hydrocephalus was more frequent in B6 (40%) compared to J129 (none). The hydrocephalus rate was increased by postnatal glycine challenge in B6 mice, more so when delivered from the first neonatal week than from the fourth. Mutant mice had reduced weight gain following weaning until the eighth postnatal week, which was exacerbated by glycine loading. The electrographic spike rate was increased in mutant mice following glycine loading, but no seizures were observed. The alpha/delta band intensity ratio was decreased in the left cortex in female J129 mice, which were less active in an open field test and explored less in a Y-maze, suggesting an encephalopathic effect. Mutant mice showed no evidence of memory dysfunction. This partial recapitulation of human symptoms and biochemistry will facilitate the evaluation of new therapeutic approaches with an early postnatal time window likely most effective. Take home message A mouse model of nonketotic hyperglycinemia is described that shows postnatal abnormalities in glycine levels, neural tube defects, body weight, electroencephalographic recordings, and in activity in young mice making it amenable for the evaluation of novel treatment interventions. Author contributions Study concept and design: JVH, MHM, NB, KNMAnimal study data: MAS, HJ, NB, MHM, JC, CBBiochemical and genetic studies: MAS, RAVH, MWFStatistical analysis: NB, JVHFirst draft writing: JVH, NB, MHMCritical rewriting: MAS, NB, MHM, TAB, JC, MWF, KNM, JVHFinal responsibility, guarantor, and communicating author: JVH. Competing interest statement The University of Colorado (JVH, MS, KNM, HJ) has the intention to file Intellectual property protection for certain biochemical treatments of NKH. Otherwise, the authors have stated that they had no interests that might be perceived as posing a conflict or bias to this subject matter. Funding support Financial support is acknowledged form the NKH Crusaders, Brodyn's Friends, Nora Jane Almany Foundation, the Dickens Family Foundation, the Lucas John Foundation, Les Petits Bourdons, Joseph's Fund, the Barnett Family, Maud & Vic Foundation, Lucy's BEElievers fund, Hope for NKH, Madi's Mission NKH fund, and from Dr. and Ms. Shaw, and the University of Colorado Foundation NKH research fund. The study was supported by a grant (CNS-X-19-103) from the University of Colorado School of Medicine and the Colorado Clinical Translational Science Institute, which is supported by NIH/NCATS Colorado CTSA Grant Number UL1 TR002535. Contents are the authors' sole responsibility and do not necessarily represent official NIH views. All funding sources had no role in the design or execution of the study, the interpretation of data, or the writing of the study. Ethics approval on Laboratory Animal Studies Mouse studies were carried out with approval from the Institutional Animal Care and Use Committee of the University of Colorado Anschutz Medical Campus (IACUC# 00413). Data sharing statement The data that support the findings of this study are available from the corresponding author upon reasonable request.
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de Koning TJ. White matter abnormalities in amino acid disorders and organic acidurias. HANDBOOK OF CLINICAL NEUROLOGY 2024; 204:173-196. [PMID: 39322378 DOI: 10.1016/b978-0-323-99209-1.00023-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/27/2024]
Abstract
Inborn errors of metabolism (IEMs) are traditionally the domain of pediatricians and internists for metabolic diseases. In general, neurologists only become involved when these disorders are complicated by neurologic symptoms such as seizures, developmental delay, or motor problems. However, in recent years and mainly due to the successes of next-generation sequencing, the number of IEMs primarily presenting with neurologic symptoms and not detected by classic biochemical testing has grown significantly. This in particular relates to disorders in the biosynthesis of amino acids. Therefore, I will start by discussing defects in the synthesis pathways of the amino acids serine, glutamine, proline, and asparagine. In these disorders, the amino acid can be low in body fluids with biochemical testing, but more frequently are completely normal and although are in different metabolic pathways, they share many clinical features such as hypomyelination and white matter abnormalities. Next, I will discuss classic amino acid disorders and organic acid disorders due to defects in breakdown pathways characterized by elevations of key metabolites in body fluids and associated with neurologic abnormalities and white matter changes on MRI.
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Affiliation(s)
- T J de Koning
- Department of Clinical Sciences, University of Lund, Lund, Sweden; Expertise Center Movement Disorders Groningen, University Medical Center Groningen, Department of Genetics and Neurology, Groningen, The Netherlands.
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8
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Huynh MT, Landais E, Agathe JMDS, Panchout A, Caroline DVDBL, Bruel H. Novel homozygous GLDC variant causing late-onset glycine encephalopathy: A case report and updated review of the literature. Mol Genet Metab Rep 2023; 34:100959. [PMID: 36817643 PMCID: PMC9932748 DOI: 10.1016/j.ymgmr.2023.100959] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2022] [Revised: 01/31/2023] [Accepted: 01/31/2023] [Indexed: 02/08/2023] Open
Abstract
Glycine encephalopathy (MIM #605899) is an autosomal recessive inborn error of metabolism caused by pathogenic variants in three genes GLDC, AMT, GCSH encoding glycine cleavage enzyme system. We report an 8-year-old boy with late-onset glycine encephalopathy who harbors a novel homozygous GLDC likely pathogenic variant c.707G > A p.(Arg236Gln). Polyhydramnios was noted at fetal ultrasound. He displayed global developmental delay, craniofacial dysmorphism, convulsions. Our report expands the phenotypic and genetic spectrum of late-onset nonketotic hyperglycinemia.
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Affiliation(s)
- Minh-Tuan Huynh
- Medical Genetics Department, Vinmec Times City International Hospital-Times City, HaNoi, Viet Nam
- Centre Hospitalier du Havre, Unité de Génétique Clinique, 29 Avenue Pierre Mendès-France, 76290 Montivilliers, France
- Corresponding author at: Medical Genetics Department, Vinmec Times City International Hospital-Times City, 458 Minh Khai, Hai Ba Trung District, VietNam.
| | - Emilie Landais
- Laboratoire de Génétique, CHRU de Reims, 45 rue Cognacq-Jay, 51092 Reims, France
| | | | - Anne Panchout
- Centre Hospitalier du Havre, Service de Gynécologie, 29 Avenue Pierre Mendès-France, 76290 Montivilliers, France
| | | | - Henri Bruel
- Centre Hospitalier du Havre, Service de Néonatologie, 29 Avenue Pierre Mendès-France, 76290 Montivilliers, France
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Shelkowitz E, Saneto RP, Al-Hertani W, Lubout CMA, Stence NV, Brown MS, Long P, Walleigh D, Nelson JA, Perez FE, Shaw DWW, Michl EJ, Van Hove JLK. Ketogenic diet as a glycine lowering therapy in nonketotic hyperglycinemia and impact on brain glycine levels. Orphanet J Rare Dis 2022; 17:423. [PMID: 36471344 PMCID: PMC9720968 DOI: 10.1186/s13023-022-02581-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2022] [Accepted: 11/20/2022] [Indexed: 12/11/2022] Open
Abstract
BACKGROUND Nonketotic hyperglycinemia (NKH) is a severe neurometabolic disorder characterized by increased glycine levels. Current glycine reduction therapy uses high doses of sodium benzoate. The ketogenic diet (KD) may represent an alternative method of glycine reduction. AIM We aimed to assess clinical and biochemical effects of two glycine reduction strategies: high dose benzoate versus KD with low dose benzoate. METHODS Six infants with NKH were first treated with high dose benzoate therapy to achieve target plasma glycine levels, and then switched to KD with low dose benzoate. They were evaluated as clinically indicated by physical examination, electroencephalogram, plasma and cerebral spinal fluid amino acid levels. Brain glycine levels were monitored by magnetic resonance spectroscopy (MRS). RESULTS Average plasma glycine levels were significantly lower with KD compared to benzoate monotherapy by on average 28%. Two infants underwent comparative assessments of brain glycine levels via serial MRS. A 30% reduction of brain glycine levels was observed in the basal ganglia and a 50% reduction in the white matter, which remained elevated above normal, and was equivalent between the KD and high dose benzoate therapies. CSF analysis obtained while participants remained on the KD showed a decrease in glycine, serine and threonine levels, reflecting their gluconeogenetic usage. Clinically, half the patients had seizure reduction on KD, otherwise the clinical impact was variable. CONCLUSION KD is an effective glycine reduction method in NKH, and may provide a more consistent reduction in plasma glycine levels than high-dose benzoate therapy. Both high-dose benzoate therapy and KD equally reduced but did not normalize brain glycine levels even in the setting of low-normal plasma glycine.
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Affiliation(s)
- Emily Shelkowitz
- Section of Clinical Genetics and Metabolism, Department of Pediatrics, University of Colorado, Education 2 South, L28-4114, East 17Th Avenue, Aurora, CO, 80045, USA
| | - Russell P Saneto
- Division of Pediatric Neurology, Department of Neurology, Center for Integrative Brain Research, Seattle Children's Research Institute, Seattle Children's Hospital, Seattle, WA, 98105, USA
| | - Walla Al-Hertani
- Division of Genetics and Genomics, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Charlotte M A Lubout
- Section of Metabolic Diseases, Beatrix Children's Hospital, University of Groningen, University Medical Center, Groningen, Groningen, The Netherlands
| | | | - Mark S Brown
- Department of Radiology, University of Colorado, Aurora, CO, USA
| | - Patrick Long
- Section of Clinical Genetics and Metabolism, Department of Pediatrics, University of Colorado, Education 2 South, L28-4114, East 17Th Avenue, Aurora, CO, 80045, USA
| | - Diana Walleigh
- Section of Child Neurology, Department of Pediatrics, University of Colorado, Aurora, CO, USA
| | - Julie A Nelson
- Section of Child Neurology, Department of Pediatrics, University of Colorado, Aurora, CO, USA
| | - Francisco E Perez
- Department of Radiology, Seattle Children's Hospital, University of Washington, Seattle, WA, USA
| | - Dennis W W Shaw
- Department of Radiology, Seattle Children's Hospital, University of Washington, Seattle, WA, USA
| | - Emma J Michl
- Division of Genetics and Genomics, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Johan L K Van Hove
- Section of Clinical Genetics and Metabolism, Department of Pediatrics, University of Colorado, Education 2 South, L28-4114, East 17Th Avenue, Aurora, CO, 80045, USA.
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Bhumika S, Basalingappa KM, Gopenath TS, Basavaraju S. Glycine encephalopathy. THE EGYPTIAN JOURNAL OF NEUROLOGY, PSYCHIATRY AND NEUROSURGERY 2022; 58:132. [PMID: 36415754 PMCID: PMC9672649 DOI: 10.1186/s41983-022-00567-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2022] [Accepted: 10/19/2022] [Indexed: 11/18/2022] Open
Abstract
Inherited neurotransmitter diseases are a subset of rare neurometabolic disorders characterized by hereditary deficiencies in neurotransmitter metabolism or transport. Non-ketotic hyperglycinaemia (NKH), called glycine encephalopathy, is an autosomal recessive glycine metabolism disorder characterized by an abnormal accumulation of glycine in all bodily tissues, including the CNS. The SLC6A9 gene, which codes for the GLYT1 protein, a biochemical abnormality in the GCS, and dihydrolipoamide dehydrogenase enzymes, which function as a GCS component, are responsible for the neonatal form's symptoms, which include progressive encephalopathy, hypotonia, seizures, and occasionally mortality in the first few days of life. By changing the MAPK signalling pathways, glycine deprivation in the brain damages neurons by increasing NMDA receptor activation, increasing intracellular Ca levels, and leading to DNA breakage and cell death in the neuron region. In addition to the previously mentioned clinical diagnosis, NKH or GE would be determined by MLPA and 13C glycine breath tests. Pediatricians, surgeons, neurologists, and geneticists treat NKH and GE at the newborn period; there is no cure for either condition.
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Affiliation(s)
- S. Bhumika
- Division of Molecular Biology, School of Life Sciences, JSS Academy of Higher Education and Research, Mysuru, 570015 India
| | - Kanthesh M. Basalingappa
- Division of Molecular Biology, School of Life Sciences, JSS Academy of Higher Education and Research, Mysuru, 570015 India
| | - T. S. Gopenath
- Department of Biotechnology and Bioinformatics, School of Life Sciences, JSS AHER, Mysuru, 570015 India
| | - Suman Basavaraju
- Department of Periodontology, JSS Dental College and Hospital, S.S. Nagar, Mysuru, 570015 India
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McCarthy L, Verma G, Hangel G, Neal A, Moffat BA, Stockmann JP, Andronesi OC, Balchandani P, Hadjipanayis CG. Application of 7T MRS to High-Grade Gliomas. AJNR Am J Neuroradiol 2022; 43:1378-1395. [PMID: 35618424 PMCID: PMC9575545 DOI: 10.3174/ajnr.a7502] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2021] [Accepted: 02/11/2022] [Indexed: 01/26/2023]
Abstract
MRS, including single-voxel spectroscopy and MR spectroscopic imaging, captures metabolites in high-grade gliomas. Emerging evidence indicates that 7T MRS may be more sensitive to aberrant metabolic activity than lower-field strength MRS. However, the literature on the use of 7T MRS to visualize high-grade gliomas has not been summarized. We aimed to identify metabolic information provided by 7T MRS, optimal spectroscopic sequences, and areas for improvement in and new applications for 7T MRS. Literature was found on PubMed using "high-grade glioma," "malignant glioma," "glioblastoma," "anaplastic astrocytoma," "7T," "MR spectroscopy," and "MR spectroscopic imaging." 7T MRS offers higher SNR, modestly improved spatial resolution, and better resolution of overlapping resonances. 7T MRS also yields reduced Cramér-Rao lower bound values. These features help to quantify D-2-hydroxyglutarate in isocitrate dehydrogenase 1 and 2 gliomas and to isolate variable glutamate, increased glutamine, and increased glycine with higher sensitivity and specificity. 7T MRS may better characterize tumor infiltration and treatment effect in high-grade gliomas, though further study is necessary. 7T MRS will benefit from increased sample size; reductions in field inhomogeneity, specific absorption rate, and acquisition time; and advanced editing techniques. These findings suggest that 7T MRS may advance understanding of high-grade glioma metabolism, with reduced Cramér-Rao lower bound values and better measurement of smaller metabolite signals. Nevertheless, 7T is not widely used clinically, and technical improvements are necessary. 7T MRS isolates metabolites that may be valuable therapeutic targets in high-grade gliomas, potentially resulting in wider ranging neuro-oncologic applications.
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Affiliation(s)
- L McCarthy
- From the Department of Neurosurgery (L.M., C.G.H.), Icahn School of Medicine at Mount Sinai, Mount Sinai Health System, New York, New York
| | - G Verma
- BioMedical Engineering and Imaging Institute (G.V., P.B.), Icahn School of Medicine at Mount Sinai, New York, New York
| | - G Hangel
- Department of Neurosurgery (G.H.)
- High-field MR Center (G.H.), Department of Biomedical Imaging and Image-Guided Therapy, Medical University of Vienna, Vienna, Austria
| | - A Neal
- Department of Medicine (A.N.), Royal Melbourne Hospital, University of Melbourne, Melbourne, Australia
- Department of Neurology (A.N.), Royal Melbourne Hospital, Melbourne, Australia
| | - B A Moffat
- The Melbourne Brain Centre Imaging Unit (B.A.M.), Department of Radiology, The University of Melbourne, Melbourne, Australia
| | - J P Stockmann
- A. A. Martinos Center for Biomedical Imaging (J.P.S., O.C.A.), Massachusetts General Hospital, Charlestown, Massachusetts
- Harvard Medical School (J.P.S., O.C.A.), Boston, Massachusetts
| | - O C Andronesi
- A. A. Martinos Center for Biomedical Imaging (J.P.S., O.C.A.), Massachusetts General Hospital, Charlestown, Massachusetts
- Harvard Medical School (J.P.S., O.C.A.), Boston, Massachusetts
| | - P Balchandani
- BioMedical Engineering and Imaging Institute (G.V., P.B.), Icahn School of Medicine at Mount Sinai, New York, New York
| | - C G Hadjipanayis
- From the Department of Neurosurgery (L.M., C.G.H.), Icahn School of Medicine at Mount Sinai, Mount Sinai Health System, New York, New York
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12
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Trofimova AV, Reddy KM. Imaging of Inherited Metabolic and Endocrine Disorders. Clin Perinatol 2022; 49:657-673. [PMID: 36113928 DOI: 10.1016/j.clp.2022.05.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
"Inherited metabolic disorders represent a large group of disorders of which approximately 25% present in neonatal period with acute metabolic decompensation, rapid clinical deterioration, and often nonspecific imaging findings. Neonatal onset signifies the profound severity of the metabolic abnormality compared with cases with later presentation and necessitates rapid diagnosis and urgent therapeutic measures in an attempt to decrease the extent of brain injury and prevent grave neurologic sequela or death. Here, the authors discuss classification and clinical and imaging findings in a spectrum of metabolic and endocrine disorders with neonatal presentation."
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Affiliation(s)
- Anna V Trofimova
- Children's Healthcare of Atlanta, Radiology Department, 1405 Clifton Road NE, Atlanta, GA 30322, USA; Emory University, Department of Radiology and Imaging Sciences, 1364 Clifton Road NE, Atlanta, GA, 30322, USA.
| | - Kartik M Reddy
- Children's Healthcare of Atlanta, Radiology Department, 1405 Clifton Road NE, Atlanta, GA 30322, USA; Emory University, Department of Radiology and Imaging Sciences, 1364 Clifton Road NE, Atlanta, GA, 30322, USA
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13
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Ning JJ, Li F, Li SQ. Clinical and genetic analysis of nonketotic hyperglycinemia: A case report. World J Clin Cases 2022; 10:7982-7988. [PMID: 36158497 PMCID: PMC9372859 DOI: 10.12998/wjcc.v10.i22.7982] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/12/2022] [Revised: 05/19/2022] [Accepted: 07/06/2022] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND Nonketotic hyperglycinemia (NKH) is a rare autosomal recessive genetic disorder of abnormal glycine metabolism caused by insufficient activity of the glycine cleavage enzyme system. Glycine is believed to function mainly as an inhibitory neurotransmitter, but it can also act as a co-agonist of the N-methyl-D-aspartate (NMDA) receptor. The accumulation of a large amount of glycine in the brain leads to neuronal and axonal injury via overactivation of NMDA receptors located in the hippocampus, cerebral cortex, olfactory bulb, and cerebellum and to stimulation of the inhibitory function of glycine receptors located in the spinal cord and brain stem, resulting in central apnea, hiccups, and hypotonia in the early stage of the disease.
CASE SUMMARY The child described in this report had typical clinical manifestations of NKH, such as hiccups, disturbance of consciousness, hypotonia, and convulsions, within the first week after birth. Whole-exome genetic testing revealed that the child had a compound heterozygous mutation, namely, c.395C>A (p.S132X) and c.2182G>A (p.G728R), in the GLDC gene, and he was diagnosed with NKH. For treatment, we administered an oral levetiracetam solution and added topiramate and prednisone for epilepsy control, but the epilepsy remained uncontrollable. Ketogenic diet therapy was started at 6 mo of age, his seizures were significantly reduced, and there were no obvious adverse reactions during ketogenic treatment. Furthermore, we found that with the development of the disease, high levels of serum glycine decreased or even disappeared without intervention, and as the disease progressed, the corpus callosum became dysplastic.
CONCLUSION This case shows that plasma glycine levels cannot be used to evaluate the prognosis of NKH, that the development of the corpus callosum can be affected by NKH, and that a ketogenic diet may be effective for seizure control in NKH patients.
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Affiliation(s)
- Jun-Jie Ning
- Department of Pediatric Intensive Care Unit, First People's Hospital of Zigong City, Zigong 643000, Sichuan Province, China
| | - Feng Li
- Department of Pediatric Intensive Care Unit, First People's Hospital of Zigong City, Zigong 643000, Sichuan Province, China
| | - Sheng-Qiu Li
- Department of Pediatric Intensive Care Unit, First People's Hospital of Zigong City, Zigong 643000, Sichuan Province, China
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14
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Swanson MA, Miller K, Young SP, Tong S, Ghaloul‐Gonzalez L, Neira‐Fresneda J, Schlichting L, Peck C, Gabel L, Friederich MW, Van Hove JLK. Cerebrospinal fluid amino acids glycine, serine, and threonine in nonketotic hyperglycinemia. J Inherit Metab Dis 2022; 45:734-747. [PMID: 35357708 PMCID: PMC9543955 DOI: 10.1002/jimd.12500] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/23/2022] [Revised: 03/24/2022] [Accepted: 03/28/2022] [Indexed: 01/30/2023]
Abstract
Nonketotic hyperglycinemia (NKH) is caused by deficient glycine cleavage enzyme activity and characterized by elevated brain glycine. Metabolism of glycine is connected enzymatically to serine through serine hydroxymethyltransferase and shares transporters with serine and threonine. We aimed to evaluate changes in serine and threonine in NKH patients, and relate this to clinical outcome severity. Age-related reference values were developed for cerebrospinal fluid (CSF) serine and threonine from 274 controls, and in a cross-sectional study compared to 61 genetically proven NKH patients, categorized according to outcome. CSF d-serine and l-serine levels were stereoselectively determined in seven NKH patients and compared to 29 age-matched controls. In addition to elevated CSF glycine, NKH patients had significantly decreased levels of CSF serine and increased levels of CSF threonine, even after age-adjustment. The CSF serine/threonine ratio discriminated between NKH patients and controls. The CSF glycine/serine aided in discrimination between severe and attenuated neonates with NKH. Over all ages, the CSF glycine, serine and threonine had moderate to fair correlation with outcome classes. After age-adjustment, only the CSF glycine level provided good discrimination between outcome classes. In untreated patients, d-serine was more reduced than l-serine, with a decreased d/l-serine ratio, indicating a specific impact on d-serine metabolism. We conclude that in NKH the elevation of glycine is accompanied by changes in l-serine, d-serine and threonine, likely reflecting a perturbation of the serine shuttle and metabolism, and of one-carbon metabolism. This provides additional guidance on diagnosis and prognosis, and opens new therapeutic avenues to be explored.
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Affiliation(s)
- Michael A. Swanson
- Section of Clinical Genetics and Metabolism, Department of PediatricsUniversity of ColoradoAuroraColoradoUSA
| | - Kristen Miller
- Department of Pediatrics, Child Health Biostatistics CoreUniversity of Colorado and Children's Hospital ColoradoAuroraColoradoUSA
| | - Sarah P. Young
- Division of Medical Genetics, Department of PediatricsDuke University School of MedicineDurhamNorth CarolinaUSA
| | - Suhong Tong
- Department of Pediatrics, Child Health Biostatistics CoreUniversity of Colorado and Children's Hospital ColoradoAuroraColoradoUSA
| | - Lina Ghaloul‐Gonzalez
- Division of Genetic and Genomic Medicine, Department of PediatricsUniversity of Pittsburgh School of MedicinePittsburghPennsylvaniaUSA
- Department of Human GeneticsGraduate School of Public Health, University of PittsburghPittsburghPennsylvaniaUSA
| | | | - Lisa Schlichting
- Department of Pathology and Laboratory MedicineChildren's Hospital ColoradoAuroraColoradoUSA
| | - Cheryl Peck
- Department of Pathology and Laboratory MedicineChildren's Hospital ColoradoAuroraColoradoUSA
| | - Linda Gabel
- Department of Pathology and Laboratory MedicineChildren's Hospital ColoradoAuroraColoradoUSA
| | - Marisa W. Friederich
- Section of Clinical Genetics and Metabolism, Department of PediatricsUniversity of ColoradoAuroraColoradoUSA
- Department of Pathology and Laboratory MedicineChildren's Hospital ColoradoAuroraColoradoUSA
| | - Johan L. K. Van Hove
- Section of Clinical Genetics and Metabolism, Department of PediatricsUniversity of ColoradoAuroraColoradoUSA
- Department of Pathology and Laboratory MedicineChildren's Hospital ColoradoAuroraColoradoUSA
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15
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Alfonsi C, Stephan-Otto C, Cortès-Saladelafont E, Palacios NJ, Podzamczer-Valls I, Cruz NG, Jiménez MRD, Micó SI, Vila MT, Jeltsch K, Hübschmann OK, Opladen T, Fragua RV, Gómez T, Fortuny OA, Jiménez IG, Laso EL, Martínez AR, López JM, Garcia-Cazorla À. Volumetric study of brain MRI in a cohort of patients with neurotransmitter disorders. Neuroradiology 2022; 64:2179-2190. [PMID: 35662359 DOI: 10.1007/s00234-022-02989-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2022] [Accepted: 05/29/2022] [Indexed: 11/27/2022]
Abstract
PURPOSE Inborn errors of neurotransmitters are rare monogenic diseases. In general, conventional neuroimaging is not useful for diagnosis. Nevertheless, advanced neuroimaging techniques could provide novel diagnosis and prognosis biomarkers. We aim to describe cerebral volumetric findings in a group of Spanish patients with neurotransmitter disorders. METHODS Fifteen 3D T1-weighted brain images from the International Working Group on Neurotransmitter related Disorders Spanish cohort were assessed (eight with monoamine and seven with amino acid disorders). Volumes of cortical and subcortical brain structures were obtained for each patient and then compared with those of two healthy individuals matched by sex and age. RESULTS Regardless of the underlying disease, patients showed a smaller total cerebral tissue volume, which was apparently associated with clinical severity. A characteristic volumetric deficit pattern, including the right Heschl gyrus and the bilateral occipital gyrus, was identified. In severe cases, a distinctive pattern comprised the middle and posterior portions of the right cingulate, the left superior motor area and the cerebellum. In succinate semialdehyde dehydrogenase deficiency, volumetric affection seems to worsen over life. CONCLUSION Despite the heterogeneity and limited size of our cohort, we found novel and relevant data. Total volume deficit appears to be a marker of severity, regardless of the specific neurotransmitter disease and irrespective of the information obtained from conventional neuroimaging. Volumetric assessment of individual brain structures could provide a deeper knowledge about pathophysiology, disease severity and specific clinical traits.
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Affiliation(s)
- Chiara Alfonsi
- Inborn Errors of Metabolism Unit, Pediatric Neurology Department, Institut de Recerca Sant Joan de Déu, and MetabERN, Hospital Sant Joan de Déu, Passeig Sant Joan De Deu Nº 2, 08950, Esplugues De Llobregat, Barcelona, Spain.,Department of Human Neuroscience, Sapienza, University of Rome, Via dei Sabelli n.108, 00185, Rome, Italy
| | - Christian Stephan-Otto
- Institut de Recerca Sant Joan de Déu, Pg Sant Joan De Deu Nº 2, 08950, Esplugues De Llobregat, Barcelona, Spain.,Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Av. Monforte de Lemos, 3-5. Pabellón 11. Planta 0, 28029, Madrid, Spain
| | - Elisenda Cortès-Saladelafont
- Unit of Inherited Metabolic Diseases and Neuropediatrics, Hospital German Trias I Pujol, Carretera de Canyet s/n, 08916, Badalona, Spain.,Universitat Autònoma de Barcelona, Plaza Cívica, Bellaterra, Cerdanyola del Vallès, 08193, Barcelona, Spain
| | - Natalia Juliá Palacios
- Inborn Errors of Metabolism Unit, Pediatric Neurology Department, Institut de Recerca Sant Joan de Déu, and MetabERN, Hospital Sant Joan de Déu, Passeig Sant Joan De Deu Nº 2, 08950, Esplugues De Llobregat, Barcelona, Spain
| | - Inés Podzamczer-Valls
- Universitat Autònoma de Barcelona, Plaza Cívica, Bellaterra, Cerdanyola del Vallès, 08193, Barcelona, Spain.,Hospital de La Santa Creu I Sant Pau, Carrer de Sant Antoni Maria Claret n. 167, 08025, Barcelona, Spain
| | - Nuria Gutiérrez Cruz
- Department of Pediatrics, Hospital Universitario Severo Ochoa, Av. de Orellana s/n, 28911, Leganés, Spain
| | - María Rosario Domingo Jiménez
- Department of Pediatric Neurology, Hospital Universitario Virgen de La Arrixaca, Ctra. Madrid-Cartagena s/n, 30120, El Palmar, Murcia, Murcia, Spain
| | - Salvador Ibáñez Micó
- Department of Pediatric Neurology, Hospital Universitario Virgen de La Arrixaca, Ctra. Madrid-Cartagena s/n, 30120, El Palmar, Murcia, Murcia, Spain
| | - Miguel Tomás Vila
- Department of Neurology, Hospital La Fe, Avinguda de Fernando Abril Martorell n.106, 46026, Valencia, Spain
| | - Kathrin Jeltsch
- Division of Child Neurology and Metabolic Disorders, University Children's Hospital Heidelberg and MetabERN, Im Neuenheimer Feld 430, 69120, Heidelberg, Germany
| | - Oya Kuseyri Hübschmann
- Division of Child Neurology and Metabolic Disorders, University Children's Hospital Heidelberg and MetabERN, Im Neuenheimer Feld 430, 69120, Heidelberg, Germany
| | - Thomas Opladen
- Division of Child Neurology and Metabolic Disorders, University Children's Hospital Heidelberg and MetabERN, Im Neuenheimer Feld 430, 69120, Heidelberg, Germany
| | - Ramón Velázquez Fragua
- Department of Pediatric Neurology, Hospital La Paz, C. de Pedro Rico n. 6, 28029, Madrid, Spain
| | - Teresa Gómez
- Department of Psychiatry, Hospital General de Granollers, Carrer de Francesc Ribas s/n, 08402, Granollers, Spain
| | - Oscar Alcoverro Fortuny
- Department of Psychiatry, Hospital General de Granollers, Carrer de Francesc Ribas s/n, 08402, Granollers, Spain
| | - Inmaculada García Jiménez
- Metabolic Disorders Unit, Hospital Universitario Miguel Servet, P.º Isabel La Católica, 1-3, 50009, Saragossa, Spain
| | - Eduardo López Laso
- Pediatric Neurology Unit, Department of Pediatrics, University Hospital Reina Sofía, IMIBIC, Av. Menendez Pidal S/N, 14004, Córdoba, Spain.,Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), C. de Melchor Fernández Almagro n. 3, 28029, Madrid, Spain
| | - Ana Roche Martínez
- Department of Pediatrics, Hospital Parc Tauli, Parc Taulí n. 1, 08208, Sabadell, Spain
| | - Jordi Muchart López
- Department of Radiology, Hospital Sant Joan de Déu, Pg Sant Joan De Deu Nº 2, 08950, Esplugues De Llobregat, Barcelona, Spain
| | - Àngels Garcia-Cazorla
- Inborn Errors of Metabolism Unit, Pediatric Neurology Department, Institut de Recerca Sant Joan de Déu, and MetabERN, Hospital Sant Joan de Déu, Passeig Sant Joan De Deu Nº 2, 08950, Esplugues De Llobregat, Barcelona, Spain. .,Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), C. de Melchor Fernández Almagro n. 3, 28029, Madrid, Spain.
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16
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Garg M, Goraya J, Kochar G, Jain V. ITPA-associated developmental and epileptic encephalopathy: characteristic neuroradiological features with novel clinical and biochemical findings. Epileptic Disord 2022; 24:583-588. [PMID: 35770779 DOI: 10.1684/epd.2022.1424] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2021] [Accepted: 02/08/2022] [Indexed: 11/17/2022]
Abstract
Developmental and epileptic encephalopathies (DEE) in children have an everexpanding range of rare causes. Mutations in ITPA have been recently described as causative of DEE, but only a small number of patients have been reported so far. We describe two Indian children with novel variants in the ITPA gene. Both patients had characteristic, previously described, neuroradiological findings that helped us suspect this condition even before genetic evaluation. In addition, we present new and rarely reported clinical findings associated with this condition: migrating partial epilepsy, fever-triggered seizures, movement disorder including oculogyria and dystonic tremor. One of the patients also had high cerebrospinal fluid glycine levels. Both patients had drug-responsive epilepsy, in contrast to drug-resistant seizures in previously reported patients. These patients reiterate the utility of awareness of specific neuroradiological findings and subsequent genetic evaluation to help make a precise diagnosis. Our report also extends the clinical spectrum and provides insight into possible biochemical causes for the neuroimaging findings seen in this condition.
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17
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Nonketotic Hyperglycinemia: Insight into Current Therapies. J Clin Med 2022; 11:jcm11113027. [PMID: 35683414 PMCID: PMC9181064 DOI: 10.3390/jcm11113027] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2022] [Revised: 05/19/2022] [Accepted: 05/24/2022] [Indexed: 12/10/2022] Open
Abstract
Nonketotic hyperglycinemia (NKH) is a rare inborn error of glycine metabolism that is characterized by the accumulation of glycine in all tissues, especially in the central nervous system (CNS). Based on clinical outcomes, NKH can be divided into two forms, i.e., severe and attenuated NKH. A poor prognosis, including no developmental progress and intractable epilepsy, is typical of severe NKH, whereas patients with the attenuated form present with varied symptoms and neurodevelopmental outcomes. So far, no causal treatment of NKH is known. Currently, the therapy is based on sodium benzoate and NMDA (The N-methyl-D-aspartate receptor) receptor site antagonists (dextromethorphan, ketamine). Different clinical outcomes of the therapy raise doubts about the effectiveness of the treatment. The purpose of this review is to summarize the therapeutic potential, challenges and effectiveness of different NKH therapies.
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18
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Kuseyri Hübschmann O, Palacios NAJ, Olivella M, Guder P, Zafeiriou DI, Horvath G, Kulhánek J, Pearson TS, Kuster A, Cortès-Saladelafont E, Ibáñez S, García-Jiménez MC, Honzík T, Santer R, Jeltsch K, Garbade SF, Hoffmann GF, Opladen T, García-Cazorla Á. An integrative approach to predict severity in nonketotic hyperglycinemia. Ann Neurol 2022; 92:292-303. [PMID: 35616651 DOI: 10.1002/ana.26423] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2021] [Revised: 05/19/2022] [Accepted: 05/23/2022] [Indexed: 11/11/2022]
Abstract
OBJECTIVE Glycine encephalopathy, also known as nonketotic hyperglycinemia (NKH), is an inherited neurometabolic disorder with variable clinical course and severity, ranging from infantile epileptic encephalopathy to psychiatric disorders. A precise phenotypic characterization and an evaluation of predictive approaches are needed. METHODS Longitudinal clinical and biochemical data of 25 individuals with NKH from the patient registry of International Working Group on Neurotransmitter related Disorders were studied with in silico analyses, pathogenicity scores and molecular modeling of GLDC and AMT variants. RESULTS Symptom onset (p<0· 01) and diagnosis occur earlier in life in severe NKH (p<0· 01). Presenting symptoms affect the age at diagnosis. Psychiatric problems occur predominantly in attenuated NKH. Onset-age ≥3 months (66% specificity, 100% sensitivity, AUC = 0·87) and cerebrospinal fluid (CSF)/plasma glycine ratio ≤0· 09 (57% specificity, 100% sensitivity, AUC = 0·88) are sensitive indicators for attenuated NKH while CSF glycine concentration ≥116· 5 μmol/L (100% specificity, 93% sensitivity, AUC = 0·97) and CSF/plasma glycine ratio ≥0· 15 (100% specificity, 64% sensitivity, AUC = 0·88) are specific for severe forms. A ratio threshold of 0· 128 discriminates the overlapping range. We present ten new GLDC variants. Two mild variants resulted in attenuated, while two severe variants or one mild and one severe variant lead to severe phenotype. Based on clinical, biochemical and genetic parameter we propose a severity prediction model. INTERPRETATION This study widens the phenotypic spectrum of attenuated NKH and expands the number of pathogenic variants. The multiparametric approach provides a promising tool to predict disease severity, helping to improve clinical management strategies. This article is protected by copyright. All rights reserved.
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Affiliation(s)
- Oya Kuseyri Hübschmann
- University Children's Hospital Heidelberg, Division of Child Neurology and Metabolic Disorders, Heidelberg, Germany
| | - Natalia Alexandra Julia Palacios
- Inborn errors of metabolism Unit, Department of Neurology, Institut de Recerca Sant Joan de Déu, CIBERER-ISCIII and MetabERN, Barcelona, Spain
| | - Mireia Olivella
- Bioinformatics and Medical Statistics Group. Facultat de Ciències i Tecnologia. Universitat de Vic - Universitat Central de Catalunya (UVic-UCC), Vic, Barcelona, Spain
| | - Philipp Guder
- Children's Hospital, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Dimitrios I Zafeiriou
- First Department of Pediatrics Aristotle University of Thessaloniki Egnatia St. 106 54622, Thessaloniki, Greece
| | - Gabriella Horvath
- University of British Columbia, Department of Pediatrics, Division of Biochemical Genetics, BC Children's Hospital, Vancouver, BC, Canada
| | - Jan Kulhánek
- Department of Pediatrics and Inherited Metabolic Disorders, First Faculty of Medicine, Charles University and General University Hospital in Prague, Prague, Czech Republic
| | - Toni S Pearson
- Department of Neurology, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Alice Kuster
- Department of Neurometabolism and Metabolic Disorders, University Hospital of Nantes, Nantes, France
| | - Elisenda Cortès-Saladelafont
- Inborn errors of metabolism Unit, Department of Neurology, Institut de Recerca Sant Joan de Déu, CIBERER-ISCIII and MetabERN, Barcelona, Spain.,Inborn Errors of Metabolism and Child Neurology Unit, Department of Pediatrics, Hospital Germans Trias i Pujol, Badalona and Faculty of Medicine, Universitat Autònoma de Barcelona, Barcelona, Spain
| | - Salvador Ibáñez
- Department of Pediatric Neurology, Hospital Virgen de la Arrixaca, Murcia, Spain
| | | | - Tomáš Honzík
- Department of Pediatrics and Inherited Metabolic Disorders, First Faculty of Medicine, Charles University and General University Hospital in Prague, Prague, Czech Republic
| | - René Santer
- Children's Hospital, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Kathrin Jeltsch
- University Children's Hospital Heidelberg, Division of Child Neurology and Metabolic Disorders, Heidelberg, Germany
| | - Sven F Garbade
- University Children's Hospital Heidelberg, Dietmar-Hopp Metabolic Center, Heidelberg, Germany
| | - Georg F Hoffmann
- University Children's Hospital Heidelberg, Division of Child Neurology and Metabolic Disorders, Heidelberg, Germany
| | - Thomas Opladen
- University Children's Hospital Heidelberg, Division of Child Neurology and Metabolic Disorders, Heidelberg, Germany
| | - Ángeles García-Cazorla
- Inborn errors of metabolism Unit, Department of Neurology, Institut de Recerca Sant Joan de Déu, CIBERER-ISCIII and MetabERN, Barcelona, Spain
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19
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Whitehead MT, Lai LM, Blüml S. Clinical 1H MRS in childhood neurometabolic diseases — part 2: MRS signatures. Neuroradiology 2022; 64:1111-1126. [DOI: 10.1007/s00234-022-02918-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2021] [Accepted: 02/10/2022] [Indexed: 12/23/2022]
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20
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Wang HP, Wong LC, Hsu CJ, Hu SC, Chu YJ, Lee WT. Eye motor manifestations in children with neurometabolic disorders. J Formos Med Assoc 2021; 121:736-748. [PMID: 34561118 DOI: 10.1016/j.jfma.2021.09.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2021] [Revised: 06/11/2021] [Accepted: 09/05/2021] [Indexed: 01/15/2023] Open
Abstract
Neurometabolic diseases are complex group of rare neurogenetic disorders, which are difficult to diagnose. Patients may have toxic metabolite accumulation, inadequate energy supply, or neurotransmitter deficiency, resulting in a variety of clinical manifestations and severity with enzyme activity or transporter function defects. Multiple organ involvement is frequently seen, among which neurological symptoms and signs are one of the most encountered problems. Ocular motor problems deserve special attention for it occurs in some inborn error of metabolism. Furthermore, some are early signs or characteristic findings of certain diseases, such as the gaze palsy in Niemann-Pick disease type C and Gaucher disease or oculogyric crisis in neurotransmitter diseases. Early recognition and intervention are important for better prognosis in treatable neurometabolic disorders. In addition, ways to evaluate and describe eye movement problems also help to demonstrate the severity or clinical progression for those diagnosed with certain neurometabolic diseases. However, the complexity of eye movement and ocular motor control renders our clinical observation, recording and even anatomic localization of abnormal eye movements. Clinicians are more likely to detect early signs and unravel problems by gaining awareness of abnormal eye movement. This study amied to approach neurometabolic diseases in children via eye motor manifestations.
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Affiliation(s)
- Hsin-Pei Wang
- Department of Pediatrics, National Taiwan University Hospital YunLin branch, Yun-Lin, Taiwan
| | - Lee-Chin Wong
- Department of Pediatrics, Cathy General Hospital, Taipei, Taiwan
| | - Chia-Jui Hsu
- Department of Pediatrics, National Taiwan University Hospital Hsinchu branch, Hsinchu, Taiwan
| | - Su-Ching Hu
- Department of Pediatrics, Cathy General Hospital, Taipei, Taiwan
| | - Yen-Ju Chu
- Department of Pediatrics, National Taiwan University Hospital and National Taiwan University College of Medicine, Taipei, Taiwan
| | - Wang-Tso Lee
- Department of Pediatrics, National Taiwan University Hospital and National Taiwan University College of Medicine, Taipei, Taiwan; Graduate Institute of Brain and Mind Sciences, National Taiwan University College of Medicine, Taipei, Taiwan.
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21
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Bayrak H, Yıldız Y, Olgaç A, Kasapkara ÇS, Küçükcongar A, Zenciroğlu A, Yüksel D, Ceylaner S, Kılıç M. Genotypic and phenotypic features in Turkish patients with classic nonketotic hyperglycinemia. Metab Brain Dis 2021; 36:1213-1222. [PMID: 33791923 DOI: 10.1007/s11011-021-00718-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/09/2020] [Accepted: 03/14/2021] [Indexed: 10/21/2022]
Abstract
Nonketotic hyperglycinemia is an autosomal recessive inborn error of glycine metabolism, characterized by deficient activity of the glycine cleavage enzyme system. Classic nonketotic hyperglycinemia is caused by mutations or genomic changes in genes that encode the protein components of the glycine cleavage enzyme system. We aimed to investigate clinical, biochemical, radiological findings and molecular genetic data in ten Turkish patients with classic nonketotic hyperglycinemia. Ten Turkish patients who were diagnosed with classic nonketotic hyperglycinemia in a single center from 2013 to 2019 were included in this study. Their clinical, radiological, electrophysiological and laboratory data were collected retrospectively. Sixty percent of the patients were in neonatal group, while 40 % of the patients were infantile. There were no late-onset patients. 90 % of the patients had the severe form. All patients had developmental delay and seizures. Mortality ratio was 30 % in all groups and 50 % in the neonatal group, while no mortality was seen in infantile group. Median (range) values of cerebrospinal fluid (CSF) glycine levels, plasma glycine levels and CSF/plasma glycine ratios were 148 (15-320) µmol/L, 896 (87-1910) µmol/L, 0.17 (0.09-0.21) respectively. Diffuse hypomyelination and corpus callosum anomaly were the most common cranial MRI findings and multifocal epileptic activity and burst supression pattern were the most common electroencephalographic findings. Six patients had variants in GLDC gene and four in AMT gene; five novel variants including AMT gene deletion were detected. Prognosis was poor and treatment was not effective, especially in the severe form. Classic nonketotic hyperglycinemia causes high morbidity and mortality. Neonatal-onset disease was more common and severe than infantile-onset disease. The ratio of AMT gene variants might be higher in Turkey than other countries. AMT gene deletion also plays a role in the etiology of classic nonketotic hyperglycinemia.
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Affiliation(s)
- Harun Bayrak
- Department of Pediatrics, Sami Ulus Children Hospital, Ankara, Turkey
| | - Yılmaz Yıldız
- Metabolism Unit, Sami Ulus Children Hospital, Babur cad. No: 44, Altındağ, Ankara, 06080, Turkey
| | - Asburçe Olgaç
- Metabolism Unit, Sami Ulus Children Hospital, Babur cad. No: 44, Altındağ, Ankara, 06080, Turkey
| | - Çiğdem Seher Kasapkara
- Metabolism Unit, Sami Ulus Children Hospital, Babur cad. No: 44, Altındağ, Ankara, 06080, Turkey
| | | | | | - Deniz Yüksel
- Neurology Unit, Sami Ulus Children Hospital, Ankara, Turkey
| | - Serdar Ceylaner
- Intergen, Genetic and Rare Disease Diagnosis and Research Center, Genetic Laboratory, Ankara, Turkey
| | - Mustafa Kılıç
- Metabolism Unit, Sami Ulus Children Hospital, Babur cad. No: 44, Altındağ, Ankara, 06080, Turkey.
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22
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Majethia P, Somashekar PH, Hebbar M, Kadavigere R, Praveen BK, Girisha KM, Shukla A. Biallelic start loss variant, c.1A > G in GCSH is associated with variant nonketotic hyperglycinemia. Clin Genet 2021; 100:201-205. [PMID: 33890291 PMCID: PMC9990824 DOI: 10.1111/cge.13970] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2021] [Revised: 04/17/2021] [Accepted: 04/19/2021] [Indexed: 11/28/2022]
Abstract
The glycine cleavage system H protein (GCSH) is an integral part of the glycine cleavage system with its additional involvement in the synthesis and transport of lipoic acid. We hypothesize that pathogenic variants in GCSH can cause variant nonketotic hyperglycinemia (NKH), a heterogeneous group of disorders with findings resembling a combination of severe NKH (elevated levels of glycine in plasma and CSF, progressive lethargy, seizures, severe hypotonia, no developmental progress, early death) and mitochondriopathies (lactic acidosis, leukoencephalopathy and Leigh-like lesions on MRI). We herein report three individuals from two unrelated Indian families with clinical, biochemical, and radiological findings of variant NKH, harboring a biallelic start loss variant, c.1A > G in GCSH.
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Affiliation(s)
- Purvi Majethia
- Department of Medical Genetics, Kasturba Medical College, Manipal, Manipal Academy of Higher Education, Manipal, India
| | - Puneeth H Somashekar
- Department of Medical Genetics, Kasturba Medical College, Manipal, Manipal Academy of Higher Education, Manipal, India
| | - Malavika Hebbar
- Department of Medical Genetics, Kasturba Medical College, Manipal, Manipal Academy of Higher Education, Manipal, India
| | - Rajagopal Kadavigere
- Department of Radiodiagnosis, Kasturba Medical College, Manipal, Manipal Academy of Higher Education, Manipal, India
| | - BK Praveen
- Department of Pediatrics, Father Muller Medical College Hospital, Mangalore, India
| | - Katta Mohan Girisha
- Department of Medical Genetics, Kasturba Medical College, Manipal, Manipal Academy of Higher Education, Manipal, India
| | - Anju Shukla
- Department of Medical Genetics, Kasturba Medical College, Manipal, Manipal Academy of Higher Education, Manipal, India
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23
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Elabd HSA, Bastaki F, Khalifa M. Homozygous Novel Variants in the Glycine Decarboxylase Gene Associated with Nonketotic Hyperglycinemia in a Distinct Population. J Pediatr Genet 2021; 12:23-31. [PMID: 36684550 PMCID: PMC9848757 DOI: 10.1055/s-0041-1729741] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2020] [Accepted: 03/21/2021] [Indexed: 01/25/2023]
Abstract
Glycine encephalopathy (GE), also known as nonketotic hyperglycinemia (NKH) is an autosomal recessive disorder due to a primary defect in the glycine cleavage enzyme system. It is characterized by elevated levels of glycine in the plasma and cerebrospinal fluid (CSF) and increased CSF to plasma glycine ratio. Mutations in three genes of the mitochondrial glycine cleavage system have been found to cause NKH. Most patients have a mutation in the GLDC . In this report, we present five new patients from Middle Eastern families with NKH. They were all born to consanguineous parents and two of them have family history of similarly affected sibling(s). All patients presented with neonatal encephalopathy associated with seizures. Their diagnoses were suspected clinically and confirmed biochemically. DNA sequence analysis of the five patients revealed five different pathogenic or likely pathogenic variants in the GLDC . Three were missense variants (c.2675C > T; p.Ala892Val), (c.2512A > G; p.Asn838Asp), and (c.2943A > C; p.Lys981Asn); one was an intronic missense variant (c.1402-2A > T) leading to an exonic deletion, and one was a deletion of 42 amino acids (c.1927-?_2052 + ?del.) All variants were novel and homozygous. The pathogenicity of these variants was determined according to the American College of Medical Genetics (ACMG) variant classification and in silico analysis. Another novel homozygous variant (c.1384C > G; p.Leu462Val) was detected, which was classified as likely benign. The novel variants identified in the GLDC in these patients underlie the pathogenesis of NKH, specifically for the Middle Eastern population. This expands the mutation spectrum of NKH to include a distinct ethnic population that has not been studied before.
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Affiliation(s)
- Heba Salah Abdelkhalek Elabd
- Department of Pediatrics Genetics, Latifa Women and Children Hospital, Dubai Health Authority, Dubai, United Arab Emirates,Department of Genetics, Faculty of Medicine, Ain Shams University, Cairo, Egypt,Address for correspondence Heba Salah Abdelkhalek Elabd, MD Latifa Women and Children HospitalOud Metha Road, Al Jadaf, Dubai, PO Box 9115United Arab Emirates
| | - Fatma Bastaki
- Department of Pediatrics Genetics, Latifa Women and Children Hospital, Dubai Health Authority, Dubai, United Arab Emirates
| | - Mohamed Khalifa
- Department of Pediatrics Genetics, Latifa Women and Children Hospital, Dubai Health Authority, Dubai, United Arab Emirates
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24
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Mademont-Soler I, Casellas-Vidal D, Trujillo A, Espuña-Capote N, Maroto A, García-González MDM, Ruiz MD, Diego-Álvarez D, Queralt X, Perapoch J, Obón M. GLYT1 encephalopathy: Further delineation of disease phenotype and discussion of pathophysiological mechanisms. Am J Med Genet A 2020; 185:476-485. [PMID: 33269555 DOI: 10.1002/ajmg.a.61996] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2020] [Revised: 11/05/2020] [Accepted: 11/07/2020] [Indexed: 01/13/2023]
Abstract
GLYT1 encephalopathy is a form of glycine encephalopathy caused by disturbance of glycine transport. The phenotypic spectrum of the disease has not yet been completely described, as only four unrelated families with the disorder have been reported to date. Common features of affected patients include neonatal hypotonia, respiratory failure, encephalopathy, myoclonic jerks, dysmorphic features, and musculoeskeletal anomalies. All reported affected patients harbor biallelic genetic variants in SLC6A9. SNP array together with Sanger sequencing were performed in a newborn with arthrogryposis and severe neurological impairment. The novel genetic variant c.997delC in SLC6A9 was detected in homozygous state in the patient. At protein level, the predicted change is p.(Arg333Alafs*3), which most probably results in a loss of protein function. The variant cosegregated with the disease in the family. A subsequent pregnancy with ultrasound anomalies was also affected. The proband presented the core phenotypic features of GLYT1 encephalopathy, but also a burst suppression pattern on the electroencephalogram, a clinical feature not previously associated with the disorder. Our results suggest that the appearance of this pattern correlates with higher cerebrospinal fluid glycine levels and cerebrospinal fluid/plasma glycine ratios. A detailed discussion on the possible pathophysiological mechanisms of the disorder is also provided.
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Affiliation(s)
- Irene Mademont-Soler
- Àrea de Genètica Clínica i Consell Genètic, Laboratori Clínic Territorial Girona, Institut Català de la Salut, Girona, Spain
| | | | - Alberto Trujillo
- Servei de Pediatria, Hospital Universitari Doctor Josep Trueta, Girona, Spain
| | - Núria Espuña-Capote
- Servei de Pediatria, Hospital Universitari Doctor Josep Trueta, Girona, Spain
| | - Anna Maroto
- Servei de Ginecologia i Obstetrícia, Hospital Universitari Doctor Josep Trueta, Girona, Spain
| | | | | | | | - Xavier Queralt
- Àrea de Genètica Clínica i Consell Genètic, Laboratori Clínic Territorial Girona, Institut Català de la Salut, Girona, Spain
| | - Josep Perapoch
- Servei de Pediatria, Hospital Universitari Doctor Josep Trueta, Girona, Spain
| | - María Obón
- Àrea de Genètica Clínica i Consell Genètic, Laboratori Clínic Territorial Girona, Institut Català de la Salut, Girona, Spain
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25
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Reliability of MRI in detection and differentiation of acute neonatal/pediatric encephalopathy causes among neonatal/pediatric intensive care unit patients. THE EGYPTIAN JOURNAL OF RADIOLOGY AND NUCLEAR MEDICINE 2020. [DOI: 10.1186/s43055-020-00173-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
Abstract
Background
Causes of encephalopathy in neonates/pediatrics include hypoxic-ischemic injury (which is the most frequent cause and is defined as any impairment to the brain caused by insufficient blood flow and oxygenation), trauma, metabolic disorders, and congenital and infectious diseases. The aim of this study is to evaluate the value of MRI in detection and possible differentiation of different non-traumatic, non-infectious causes of acute neonatal/pediatric encephalopathy among NICU/PICU patients.
Results
This retrospective study included 60 selected patients according to the study inclusion and exclusion criteria; all presented with positive MRI findings for non-traumatic, non-infectious acute brain injury. Females (32, 53.3%) were affected more than males (28, 46.7%) with a mean age of 1.1 ± 1.02 years; all presented with variable neurological symptoms and signs that necessitate neonatal intensive care unit/pediatric intensive care unit (NICU/PICU) admission. The final diagnosis of the study group patients were hypoxic ischemia injury (HII) in 39 patients (65%), metachromatic leukodystrophy in 6 patients (10%), biotin-thiamine-responsive basal ganglia disease (BTBGD) and Leigh disease each in 4 patients (6.7%), periventricular leukomalacia (PVL) in 3 patients (5%), and mitochondrial encephalopathy with lactic acidosis and stroke-like episodes syndrome (MELAS) and non-ketotic hyperglycinemia (NKH) each in 2 patients (3.3%).
Conclusion
Much attention should be paid to pediatric non-traumatic brain injuries. MRI is a safe modality and should be the first radiological investigation if neurological causes are suggested but should be aided by meticulous clinical evaluation and dedicated laboratory investigations for better characterization and differentiation of various causes of non-traumatic, non-infective brain encephalopathy among NICU/PICU patients. When interpreting MRI, it is essential to have thorough relevant clinical data, gestational age at birth which is prognostic of the pattern of hypoxic-ischemic injury, and the time lag between the onset of HII and the time of performing the MR study.
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26
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Ichikawa K, Inami Y, Kaneko K. Seventeen-year long-term survival of a case of neonatal nonketotic hyperglycinemia. Pediatr Int 2020; 62:1111-1113. [PMID: 32754929 DOI: 10.1111/ped.14254] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/05/2020] [Revised: 04/01/2020] [Accepted: 04/15/2020] [Indexed: 11/29/2022]
Affiliation(s)
- Kazushi Ichikawa
- Department of Pediatrics, Fujisawa City Hospital, Kanagawa, Japan
| | - Yuki Inami
- Department of Pediatrics, Fujisawa City Hospital, Kanagawa, Japan
| | - Kaori Kaneko
- Department of Pediatrics, Fujisawa City Hospital, Kanagawa, Japan
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27
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Gropman AL, Anderson A. Novel imaging technologies for genetic diagnoses in the inborn errors of metabolism. JOURNAL OF TRANSLATIONAL GENETICS AND GENOMICS 2020; 4:429-445. [PMID: 35529470 PMCID: PMC9075742 DOI: 10.20517/jtgg.2020.09] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Many inborn errors of metabolism and genetic disorders affect the brain. The brain biochemistry may differ from that in the periphery and is not accessible by simple blood and urine sampling. Therefore, neuroimaging has proven to be a valuable tool to not only evaluate the brain structure, but also biochemistry, blood flow and function. Neuroimaging in patients with inborn errors of metabolism can include additional sequences in addition to T1 and T2-weighted imaging because in early stages, there may be no significant findings on the routine sequnces due to the lack of sensitivity or the evolution of abnormalities lags behind the ability of the imaging to detect it. In addition, findings on T1 and T2-weighted imaging of several inborn errors of metabolism may be non-specific and be seen in other non-genetic conditions. Therefore, additional neuroimaging modalities that have been employed including diffusion tensor imaging (DTI), magnetic resonance spectroscopy, functional MRI (fMRI), functional near infrared spectroscopy (fNIRS), or positron emission tomography (PET) imaging may further inform underlying changes in myelination, biochemistry, and functional connectivity. The use of Magnetic Resonance Spectroscopy in certain disorders may add a level of specificity depending upon the metabolite levels that are abnormal, as well as provide information about the process of brain injury (i.e., white matter, gray matter, energy deficiency, toxic buildup or depletion of key metabolites). It is even more challenging to understand how genetic or metabolic disorders contribute to short and/or long term changes in cognition which represent the downstream effects of IEMs. In order to image “cognition” or the downstream effects of a metabolic disorder on domains of brain function, more advanced techniques are required to analyze underlying fiber tracts or alternatively, methods such as fMRI enable generation of brain activation maps after both task based and resting state conditions. DTI can be used to look at changes in white matter tracks. Each imaging modality can explore an important aspect of the anatomy, physiology or biochemisty of the central nervous system. Their properties, pros and cons are discussed in this article. These imaging modalities will be discussed in the context of several inborn errors of metabolism including Galactosemia, Phenylketonruia, Maple syrup urine disease, Methylmalonic acidemia, Niemann-Pick Disease, type C1, Krabbe Disease, Ornithine transcarbamylase deficiency, Sjogren Larsson syndrome, Pelizeaus-Merzbacher disease, Pyruvate dehydrogenase deficiency, Nonketotic Hyperglycinemia and Fabry disease. Space constraints do not allow mention of all the disorders in which one of these modalities has been investigated, or where it would add value to diagnosis or disease progression.
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Affiliation(s)
- Andrea L Gropman
- Department of Neurology, Children's National Medical Center, Washington, DC 20010, USA
| | - Afrouz Anderson
- Department of Research, Focus Foundation, Crofton, MD 21035, USA
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