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Prasad A, Kumar P, Marithammanahalli Faneesha G, Kumar C. Non-ketotic hyperglycinaemia masquerading as a hypotonic-hyporesponsive episode following vaccination in an infant. BMJ Case Rep 2024; 17:e257093. [PMID: 38782422 DOI: 10.1136/bcr-2023-257093] [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] [Indexed: 05/25/2024] Open
Abstract
Non-ketotic hyperglycinaemia (NKH) is an inborn error of glycine metabolism with autosomal recessive inheritance. A female infant presented to our emergency department with intractable seizures, lethargy and hypotonia, 2 weeks after her routine vaccination. Detailed infective and metabolic workup revealed normal blood sugar, ketone, lactate ammonia, and a high level of glycine in serum and cerebrospinal fluid suggesting NKH. Diagnosis of NKH was further confirmed on genetic analysis for AMT gene mutation. The child showed clinical improvement with oral sodium benzoate. Here, we report the inheritance, pathophysiology, diagnostic approach, genetic confirmation, management and prognosis of a child with NKH.
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Affiliation(s)
- Arun Prasad
- Department of Pediatrics, All India Institute of Medical Sciences Patna, Patna, Bihar, India
| | - Pradeep Kumar
- Department of Pediatrics, All India Institute of Medical Sciences Patna, Patna, Bihar, India
| | | | - Chandramohan Kumar
- Department of Pediatrics, All India Institute of Medical Sciences Patna, Patna, Bihar, India
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2
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Pin JN, Leonardi L, Nosadini M, Cavicchiolo ME, Guariento C, Zarpellon A, Perilongo G, Raffagnato A, Toldo I, Baraldi E, Sartori S. Efficacy and safety of ketamine for neonatal refractory status epilepticus: case report and systematic review. Front Pediatr 2023; 11:1189478. [PMID: 37334223 PMCID: PMC10275409 DOI: 10.3389/fped.2023.1189478] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/19/2023] [Accepted: 05/23/2023] [Indexed: 06/20/2023] Open
Abstract
Background Evidence-based data on treatment of neonatal status epilepticus (SE) are scarce. We aimed to collect data on the efficacy and safety of ketamine for the treatment of neonatal SE and to assess its possible role in the treatment of neonatal SE. Methods We described a novel case and conducted a systematic literature review on neonatal SE treated with ketamine. The search was carried out in Pubmed, Cochrane, Clinical Trial Gov, Scopus and Web of Science. Results Seven published cases of neonatal SE treated with ketamine were identified and analyzed together with our novel case. Seizures typically presented during the first 24 h of life (6/8). Seizures were resistant to a mean of five antiseizure medications. Ketamine, a NMDA receptor antagonist, appeared to be safe and effective in all neonates treated. Neurologic sequelae including hypotonia and spasticity were reported for 4/5 of the surviving children (5/8). 3/5 of them were seizure free at 1-17 months of life. Discussion Neonatal brain is more susceptible to seizures due to a shift towards increased excitation because of a paradoxical excitatory effect of GABA, a greater density of NMDA receptors and higher extracellular concentrations of glutamate. Status epilepticus and neonatal encephalopathy could further enhance these mechanisms, providing a rationale for the use of ketamine in this setting. Conclusions Ketamine in the treatment of neonatal SE showed a promising efficacy and safety profile. However, further in-depth studies and clinical trials on larger populations are needed.
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Affiliation(s)
- Jacopo Norberto Pin
- Department of Women’s and Children’s Health, Paediatric Neurology and Neurophysiology Unit, University Hospital of Padua, Padova, Italy
- Master in Pediatrics and Pediatric Subspecialties, University Hospital of Padua, Padova, Italy
| | - Letizia Leonardi
- Department of Women’s and Children’s Health, Paediatric Neurology and Neurophysiology Unit, University Hospital of Padua, Padova, Italy
| | - Margherita Nosadini
- Department of Women’s and Children’s Health, Paediatric Neurology and Neurophysiology Unit, University Hospital of Padua, Padova, Italy
- Neuroimmunology Group, Paediatric Research Institute “Città della Speranza”, Padova, Italy
| | - Maria Elena Cavicchiolo
- Department of Women’s and Children’s Health, Neonatal Intensive Care Unit, University Hospital of Padua, Padova, Italy
| | - Chiara Guariento
- Department of Women’s and Children’s Health, Paediatric Neurology and Neurophysiology Unit, University Hospital of Padua, Padova, Italy
| | - Anna Zarpellon
- Department of Women’s and Children’s Health, Paediatric Neurology and Neurophysiology Unit, University Hospital of Padua, Padova, Italy
| | - Giorgio Perilongo
- Department of Women’s and Children’s Health, Paediatric Neurology and Neurophysiology Unit, University Hospital of Padua, Padova, Italy
| | - Alessia Raffagnato
- Department of Women’s and Children’s Health, Child and Adolescent Neuropsychiatric Unit, University Hospital of Padua, Padova, Italy
| | - Irene Toldo
- Department of Women’s and Children’s Health, Paediatric Neurology and Neurophysiology Unit, University Hospital of Padua, Padova, Italy
| | - Eugenio Baraldi
- Department of Women’s and Children’s Health, Neonatal Intensive Care Unit, University Hospital of Padua, Padova, Italy
| | - Stefano Sartori
- Department of Women’s and Children’s Health, Paediatric Neurology and Neurophysiology Unit, University Hospital of Padua, Padova, Italy
- Master in Pediatrics and Pediatric Subspecialties, University Hospital of Padua, Padova, Italy
- Neuroimmunology Group, Paediatric Research Institute “Città della Speranza”, Padova, Italy
- Department of Neuroscience, University Hospital of Padua, Padova, Italy
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3
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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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Daida A, Hamano SI, Ikemoto S, Hirata Y, Matsuura R, Koichihara R, Oba D, Ohashi H. Use of Perampanel and a Ketogenic Diet in Nonketotic Hyperglycinemia: A Case Report. Neuropediatrics 2020; 51:417-420. [PMID: 32176929 DOI: 10.1055/s-0040-1708536] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
BACKGROUND Nonketotic hyperglycinemia is a severe form of early onset epileptic encephalopathy caused by disturbances in the glycine cleavage system; the neurological damage is mainly attributed to overstimulation of the N-methyl-D-aspartate receptor. CASE The patient presented with a severe form of nonketotic hyperglycinemia and experienced frequent epileptic spasms and focal seizures, which were resistant to vigabatrin, adrenocorticotropic hormone therapy, and combined dextromethorphan and sodium benzoate treatments. By 9 months of age, perampanel reduced epileptic spasms by >50%. At 14 months of age, the ketogenic diet markedly reduced focal seizures and glycine levels in the cerebrospinal fluid. CONCLUSION Perampanel reduced fast excitatory neuronal activity, which was induced by an α-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid receptor, followed by prolonged electrical depolarizations due to an N-methyl-D-aspartate receptor. Furthermore, the ketogenic diet may have modulated the excessive neurotoxic cascade through the N-methyl-D-aspartate receptor. Perampanel and ketogenic diet were effective for seizure control in our patient.
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Affiliation(s)
- Atsuro Daida
- Division of Neurology, Saitama Children's Medical Center, Saitama-City, Saitama, Japan.,Department of Pediatrics, Tokyo Medical University, Shinjuku-ku, Tokyo, Japan
| | - Shin-Ichiro Hamano
- Division of Neurology, Saitama Children's Medical Center, Saitama-City, Saitama, Japan
| | - Satoru Ikemoto
- Division of Neurology, Saitama Children's Medical Center, Saitama-City, Saitama, Japan
| | - Yuko Hirata
- Division of Neurology, Saitama Children's Medical Center, Saitama-City, Saitama, Japan
| | - Ryuki Matsuura
- Division of Neurology, Saitama Children's Medical Center, Saitama-City, Saitama, Japan
| | - Reiko Koichihara
- Division of Neurology, Saitama Children's Medical Center, Saitama-City, Saitama, Japan
| | - Daiju Oba
- Division of Medical Genetics, Saitama Children's Medical Center, Saitama-City, Saitama, Japan
| | - Hirofumi Ohashi
- Division of Medical Genetics, Saitama Children's Medical Center, Saitama-City, Saitama, Japan
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Jiang TJ, Jiang JJ, Xu JL, Zhen J, Jiang PF, Gao F. [Clinical and genetic analyses of a family with atypical nonketotic hyperglycinemia caused by compound heterozygous mutations in the GLDC gene]. ZHONGGUO DANG DAI ER KE ZA ZHI = CHINESE JOURNAL OF CONTEMPORARY PEDIATRICS 2017; 19:1087-1091. [PMID: 29046206 PMCID: PMC7389275 DOI: 10.7499/j.issn.1008-8830.2017.10.011] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Received: 04/26/2017] [Accepted: 06/22/2017] [Indexed: 06/07/2023]
Abstract
Nonketotic hyperglycinemia (NKH) is an autosomal recessive hereditary disease caused by a defect in the glycine cleavage system and is classified into typical and atypical NKH. Atypical NKH has complex manifestations and is difficult to diagnose in clinical practice. This article reports a family of NKH. The parents had normal phenotypes, and the older brother and the younger sister developed this disease in the neonatal period. The older brother manifested as intractable epilepsy, severe spastic diplegia, intellectual disability, an increased level of glycine in blood and cerebrospinal fluid, an increased glycine/creatinine ratio in urine, and an increased ratio of glycine concentration in cerebrospinal fluid and blood. The younger sister manifested as delayed language development, ataxia, chorea, mental and behavior disorders induced by pyrexia, hypotonia, an increased level of glycine in cerebrospinal fluid, and an increased ratio of glycine concentration in cerebrospinal fluid and blood. High-throughput sequencing found a maternal missense mutation, c.3006C>G (p.C1002W), and a paternal nonsense mutation, c.1256C>G (p.S419X), in the GLDC gene in both patients. These two mutations were thought to be pathogenic mutations by a biological software. H293T cells transfected with these two mutants of the GLDC gene had a down-regulated activity of glycine decarboxylase. NKH has various phenotypes, and high-throughput sequencing helps to make a confirmed diagnosis. Atypical NKH is associated with the downregulated activity of glycine decarboxylase caused by gene mutations.
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Affiliation(s)
- Tie-Jia Jiang
- Department of Neurology, Children's Hospital of Zhejiang University School of Medicine, Hangzhou 310051, China.
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Piper JD, Piper PW. Benzoate and Sorbate Salts: A Systematic Review of the Potential Hazards of These Invaluable Preservatives and the Expanding Spectrum of Clinical Uses for Sodium Benzoate. Compr Rev Food Sci Food Saf 2017; 16:868-880. [PMID: 33371618 DOI: 10.1111/1541-4337.12284] [Citation(s) in RCA: 73] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2017] [Revised: 06/08/2017] [Accepted: 06/10/2017] [Indexed: 12/30/2022]
Abstract
Sodium benzoate and potassium sorbate are extremely useful agents for food and beverage preservation, yet concerns remain over their complete safety. Benzoate can react with the ascorbic acid in drinks to produce the carcinogen benzene. A few children develop allergy to this additive while, as a competitive inhibitor of D-amino acid oxidase, benzoate can also influence neurotransmission and cognitive functioning. Model organism and cell culture studies have raised some issues. Benzoate has been found to exert teratogenic and neurotoxic effects on zebrafish embryos. In addition, benzoate and sorbate are reported to cause chromosome aberrations in cultured human lymphocytes; also to be potently mutagenic toward the mitochondrial DNA in aerobic yeast cells. Whether the substantial human consumption of these compounds could significantly increase levels of such damages in man is still unclear. There is no firm evidence that it is a risk factor in type 2 diabetes. The clinical administration of sodium benzoate is of proven benefit for many patients with urea cycle disorders, while recent studies indicate it may also be advantageous in the treatment of multiple sclerosis, schizophrenia, early-stage Alzheimer's disease and Parkinson's disease. Nevertheless, exposure to high amounts of this agent should be approached with caution, especially since it has the potential to generate a shortage of glycine which, in turn, can negatively influence brain neurochemistry. We discuss here how a small fraction of the population might be rendered-either through their genes or a chronic medical condition-particularly susceptible to any adverse effects of sodium benzoate.
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Affiliation(s)
- Joseph D Piper
- Centre for Genomics and Child Health, Blizard Inst., Queen Mary Univ. of London, London, E1 2AT, United Kingdom
| | - Peter W Piper
- Dept. of Molecular Biology and Biotechnology, Univ. of Sheffield, Sheffield, S10 2TN, United Kingdom
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7
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Li HF. [Clinical and molecular genetic characteristics of nonketotic hyperglycinemia]. ZHONGGUO DANG DAI ER KE ZA ZHI = CHINESE JOURNAL OF CONTEMPORARY PEDIATRICS 2017; 19:272-274. [PMID: 28302195 PMCID: PMC7390138 DOI: 10.7499/j.issn.1008-8830.2017.03.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Received: 11/06/2016] [Accepted: 12/20/2016] [Indexed: 06/06/2023]
Affiliation(s)
- Hai-Feng Li
- Department of Rehabilitation, Children's Hospital, Zhejiang University School of Medicine, Hangzhou 310003, China
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8
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Abstract
Inborn errors of metabolism (IEM) are rare conditions that represent more than 1000 diseases, with a global prevalence of approximately 1:2000 individuals. Approximately, 40%-60% of IEM may present with epilepsy as one of the main neurologic signs. Epilepsy in IEM may appear at any age (fetal, newborn, infant, adolescent, or even adult). Different pathophysiological mechanisms may be responsible for the clinical phenotype, such as disturbances in energy metabolism (mitochondrial and fatty oxidation disorders, GLUT-1, and cerebral creatine deficiency), accumulation of complex molecules (lysosomal storage disorders), toxic mechanisms (organic acidurias and urea cycle disorders), or impairment of neurotransmission. Early diagnosis and, in some cases, an effective treatment may result in an excellent evolution of the IEM, in particularly seizure control. This review attempts to delineate a summary of IEM that may present with seizures or epilepsy and emphasizes the management in treatable conditions.
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Affiliation(s)
- Jaume Campistol
- From the *Neurology Department, Hospital Sant Joan de Déu, Barcelona University, Barcelona, Spain; Center for Biomedical Research on Rare Diseases (CIBERER), Instituto de Salud Carlos III, Madrid, Spain; Institute of Pediatric Research, Sant Joan de Déu, Barcelona, Spain.
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9
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Nonketotic Hyperglycinemia of Infants in Taiwan. Pediatr Neonatol 2016; 57:420-426. [PMID: 26947380 DOI: 10.1016/j.pedneo.2015.10.008] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/27/2015] [Revised: 10/05/2015] [Accepted: 10/16/2015] [Indexed: 11/23/2022] Open
Abstract
BACKGROUND Nonketotic hyperglycinemia (NKH) is a rare, inherited disease, with very poor outcome. It is difficult to confirm the diagnosis due to nonspecific presentations and rapid progression. The incidence was reported in a few countries. We report the clinical and genetic features of typical neonatal NKH with novel splicing mutation, c.1058+3A>C, in the intron 7 of the glycine decarboxylase (GLDC) gene. Furthermore, this study aimed to delineate the estimated incidence and clinical characteristics of NKH in the Taiwanese population. METHODS Reports of Health Promotion Administration, Ministry of Health and Welfare of Taiwan, during the period from 2000 to 2013; the Human Gene Mutation Database; and literature regarding NKH in Taiwan were reviewed. Demographic information, age of onset, clinical characteristics, genetic analysis, electroencephalography examinations, and outcome of the patients were analyzed. RESULTS The estimated incidence of NKH in the Taiwanese population was 7.2 cases per 1,000,000 live births. Among the 12 cases reported in Taiwan, more than 90% were of neonatal type. Fifty-five percent of affected patients died within 5 years, and all survivors had severe neurologic outcomes. Only three infants underwent genetic analysis during the study period. Two neonatal NKH infants had mutation in the GLDC gene, and the other one, who had late-onset NKH, had mutation in the glutaredoxin 5 gene. CONCLUSION Compared with other countries, the estimated incidence of NKH was relatively rare in the Taiwanese population. It is important to characterize all index cases at the genetic level. With more awareness of NKH, increased knowledge of gene mutation, and improvement of diagnostic tools, NKH can be diagnosed more accurately.
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Nickerson SL, Balasubramaniam S, Dryland PA, Love JM, Kava MP, Love DR, Prosser DO. Two Novel GLDC Mutations in a Neonate with Nonketotic Hyperglycinemia. J Pediatr Genet 2016; 5:174-80. [PMID: 27617160 DOI: 10.1055/s-0036-1584358] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2015] [Accepted: 09/09/2015] [Indexed: 10/21/2022]
Abstract
Nonketotic hyperglycinemia, also known as glycine encephalopathy (OMIM #605899), is an autosomal recessive disorder of glycine metabolism resulting from a defect in the glycine cleavage system. We report two novel mutations of the glycine decarboxylase (GLDC) gene observed in a compound heterozygous state in a neonate of mixed Maori and Caucasian parentage: c.395C>T p.(Ser132Leu) in exon 3, and c.256-?_334+?del p.(Ser86Valfs*119), resulting in an out-of-frame deletion of exon 2. Additionally, we describe our experience of implementing the ketogenic diet, alongside standard pharmacological therapy, and highlight its potential therapeutic benefit in severe nonketotic hyperglycinemia, particularly in seizure management.
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Affiliation(s)
- Sarah L Nickerson
- Diagnostic Genetics, LabPLUS, Auckland City Hospital, Auckland, New Zealand
| | - Shanti Balasubramaniam
- Metabolic Unit, Department of Rheumatology/Metabolic Medicine, Princess Margaret Hospital, Perth, WA, Australia; School of Paediatrics and Child Health, University of Western Australia, WA, Australia
| | - Philippa A Dryland
- Diagnostic Genetics, LabPLUS, Auckland City Hospital, Auckland, New Zealand
| | - Jennifer M Love
- Diagnostic Genetics, LabPLUS, Auckland City Hospital, Auckland, New Zealand
| | - Maina P Kava
- School of Paediatrics and Child Health, University of Western Australia, WA, Australia; Department of Paediatric Neurology, Princess Margaret Hospital for Children, Perth, WA, Australia
| | - Donald R Love
- Diagnostic Genetics, LabPLUS, Auckland City Hospital, Auckland, New Zealand
| | - Debra O Prosser
- Diagnostic Genetics, LabPLUS, Auckland City Hospital, Auckland, New Zealand
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Bjoraker KJ, Swanson MA, Coughlin CR, Christodoulou J, Tan ES, Fergeson M, Dyack S, Ahmad A, Friederich MW, Spector EB, Creadon-Swindell G, Hodge MA, Gaughan S, Burns C, Van Hove JLK. Neurodevelopmental Outcome and Treatment Efficacy of Benzoate and Dextromethorphan in Siblings with Attenuated Nonketotic Hyperglycinemia. J Pediatr 2016; 170:234-9. [PMID: 26749113 DOI: 10.1016/j.jpeds.2015.12.027] [Citation(s) in RCA: 50] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/22/2015] [Revised: 10/05/2015] [Accepted: 12/08/2015] [Indexed: 11/18/2022]
Abstract
OBJECTIVE To evaluate the impact of sodium benzoate and dextromethorphan treatment on patients with the attenuated form of nonketotic hyperglycinemia. STUDY DESIGN Families were recruited with 2 siblings both affected with attenuated nonketotic hyperglycinemia. Genetic mutations were expressed to identify residual activity. The outcome on developmental progress and seizures was compared between the first child diagnosed and treated late with the second child diagnosed at birth and treated aggressively from the newborn period using dextromethorphan and benzoate at dosing sufficient to normalize plasma glycine levels. Both siblings were evaluated with similar standardized neurodevelopmental measures. RESULTS In each sibling set, the second sibling treated from the neonatal period achieved earlier and more developmental milestones, and had a higher developmental quotient. In 3 of the 4 sibling pairs, the younger sibling had no seizures whereas the first child had a seizure disorder. The adaptive behavior subdomains of socialization and daily living skills improved more than motor skills and communication. CONCLUSIONS Early treatment with dextromethorphan and sodium benzoate sufficient to normalize plasma glycine levels is effective at improving outcome if used in children with attenuated disease with mutations providing residual activity and when started from the neonatal period.
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Affiliation(s)
| | | | | | - John Christodoulou
- Western Sydney Genetics Program, Children's Hospital at Westmead, and Disciplines of Pediatrics and Child Health and Genetic Medicine, Sydney Medical School, University of Sydney, Sydney, New South Wales, Australia
| | - Ee S Tan
- Western Sydney Genetics Program, Children's Hospital at Westmead, and Disciplines of Pediatrics and Child Health and Genetic Medicine, Sydney Medical School, University of Sydney, Sydney, New South Wales, Australia
| | - Mark Fergeson
- Department of Pediatrics, Oklahoma University, Oklahoma City, OK
| | - Sarah Dyack
- Department of Pediatrics, Dalhousie University, IWK Health Centre, Halifax, Nova Scotia, Canada
| | - Ayesha Ahmad
- Division of Pediatric Genetics, University of Michigan, Ann Arbor, MI
| | | | | | | | - M Antoinette Hodge
- Child Development Unit, Children's Hospital at Westmead, Sydney, New South Wales, Australia
| | - Sommer Gaughan
- Department of Pediatrics, University of Colorado, Aurora, CO
| | - Casey Burns
- Department of Pediatrics, University of Colorado, Aurora, CO
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Subramanian V, Kadiyala P, Hariharan P, Neeraj E. A rare case of glycine encephalopathy unveiled by valproate therapy. J Pediatr Neurosci 2015; 10:143-5. [PMID: 26167219 PMCID: PMC4489059 DOI: 10.4103/1817-1745.159200] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
Glycine encephalopathy (GE) or nonketotic hyperglycinemia is an autosomal recessive disorder due to a primary defect in glycine cleavage enzyme system. It is characterized by elevated levels of glycine in plasma and cerebrospinal fluid usually presenting with seizures, hypotonia, and developmental delay. In our case, paradoxical increase in seizure frequency on starting sodium valproate led us to diagnose GE.
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Affiliation(s)
- Velusamy Subramanian
- Department of Paediatric Neurology, Institute of Social Paediatrics, Stanley Medical College, Chennai, Tamil Nadu, India
| | - Pramila Kadiyala
- Department of Biochemistry, Institute of Child Health, Madras Medical College, Chennai, Tamil Nadu, India
| | | | - E Neeraj
- Department of Paediatrics, Institute of Social Paediatrics, Stanley Medical College, Chennai, Tamil Nadu, India
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13
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Alfadhel M, Al-Thihli K, Moubayed H, Eyaid W, Al-Jeraisy M. Drug treatment of inborn errors of metabolism: a systematic review. Arch Dis Child 2013; 98:454-61. [PMID: 23532493 PMCID: PMC3693126 DOI: 10.1136/archdischild-2012-303131] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
BACKGROUND The treatment of inborn errors of metabolism (IEM) has seen significant advances over the last decade. Many medicines have been developed and the survival rates of some patients with IEM have improved. Dosages of drugs used for the treatment of various IEM can be obtained from a range of sources but tend to vary among these sources. Moreover, the published dosages are not usually supported by the level of existing evidence, and they are commonly based on personal experience. METHODS A literature search was conducted to identify key material published in English in relation to the dosages of medicines used for specific IEM. Textbooks, peer reviewed articles, papers and other journal items were identified. The PubMed and Embase databases were searched for material published since 1947 and 1974, respectively. The medications found and their respective dosages were graded according to their level of evidence, using the grading system of the Oxford Centre for Evidence-Based Medicine. RESULTS 83 medicines used in various IEM were identified. The dosages of 17 medications (21%) had grade 1 level of evidence, 61 (74%) had grade 4, two medications were in level 2 and 3 respectively, and three had grade 5. CONCLUSIONS To the best of our knowledge, this is the first review to address this matter and the authors hope that it will serve as a quickly accessible reference for medications used in this important clinical field.
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Affiliation(s)
- Majid Alfadhel
- Division of Genetics, Department of Pediatrics, King Saud bin Abdulaziz University for Health Sciences, King Abdulaziz Medical City, PO Box 22490, Riyadh 11426, Saudi Arabia.
| | - Khalid Al-Thihli
- Genetics and Developmental Medicine Clinic, Sultan Qaboos University Hospital, Muscat, Sultanate ofOman
| | - Hiba Moubayed
- Pharmaceutical Care Services, Division of Clinical Pharmacy, King Abdulaziz Medical City, Riyadh, Saudi Arabia
| | - Wafaa Eyaid
- Division of Genetics, Department of Pediatrics, King Saud bin Abdulaziz University for Health Sciences, King Abdulaziz Medical City, Riyadh, Saudi Arabia
| | - Majed Al-Jeraisy
- Pharmaceutical Care Services, Division of Clinical Pharmacy, King Abdulaziz Medical City, Riyadh, Saudi Arabia
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Mulligan JL. Neonatal nonketotic hyperglycinemia: a case study and review of management for the advanced practice nurse. Neonatal Netw 2013; 32:95-103. [PMID: 23477976 DOI: 10.1891/0730-0832.32.2.95] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Nonketotic hyperglycinemia (NKH) is an autosomal recessive inborn error of glycine metabolism. In this article, I will present the case of baby girl S. who presented to the emergency room on Day 4 of life with severe lethargy, seizures, and respiratory depression requiring mechanical ventilation. A diagnosis of NKH was made secondary to elevated plasma and cerebrospinal fluid glycine concentrations. I will review the pathophysiology of NKH, methods of diagnosis, and the differential diagnosis. There are a variety of different pharmacologic and alternative therapies for NKH. Despite these treatments, the prognosis for infants with NKH is poor, with severe neurologic impairment, intractable seizures, and death common before 5 years of age. I will address the role of the advanced practice nurse in caring for an infant with NKH including clinical, educational, and research implications.
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15
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Dulac O. Epileptic encephalopathy with suppression-bursts and nonketotic hyperglycinemia. HANDBOOK OF CLINICAL NEUROLOGY 2013; 113:1785-1797. [PMID: 23622401 DOI: 10.1016/b978-0-444-59565-2.00048-4] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Bursts of paroxysmal activity alternating with lack of activity define the suppression-burst (SB) pattern that may be acute, in hypoxic-ischemic encephalopathy and barbiturate intoxication, or chronic in the course of early epileptic and neonatal myoclonic (NME) encephalopathies. Malformations, namely Aicardi syndrome and hemimegalencephaly, gene mutations - of ARX and MUNC18 -, and inborn errors of metabolism, namely glycine encephalopathy, are the main causes, with spasms indicating more likely a malformation whereas myoclonus indicates metabolic disorders. Although glycine encephalopathy has a very severe outcome in its classical expression, it may be transient in the neonatal period, for reasons yet not identified. Although glycine encephalopathy is the main identified cause of NME, the disorder may not cause SB, especially in cases with later onset. The biochemical bases, due to changes in one of the four proteins that compose the enzyme, are well understood, but there is no phenotype-genotype correlation. Prenatal diagnosis is based on villous biopsy. The mechanism of SB partly depends on glutamate - or glycine, the co-neurotransmitter for NMDA transmission - overflow, mainly in the immature brain but also in cases due to barbiturate intoxication. Energy supply defect may also be involved in some inborn errors of metabolism.
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Affiliation(s)
- Olivier Dulac
- Department of Pediatric Neurology, Hôpital Necker-Enfants Malades, INSERM U663, Paris, France.
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Terek D, Koroglu OA, Gunes S, Yalaz M, Akisu M, Uçar SK, Gokben S, Coker M, Kultursay N. Diagnostic tools of metabolic and structural brain disturbances in neonatal non-ketotic hyperglycinemia. Pediatr Int 2012; 54:717-20. [PMID: 23005907 DOI: 10.1111/j.1442-200x.2012.03591.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Non-ketotic hyperglycinemia (NKH) is a rare autosomal recessive disorder of glycine metabolism. We report a newborn case of NKH and discuss the effects of this rare disease on brain metabolism and structure together with amplitude-integrated electroencephalography, cranial magnetic resonance and magnetic resonance spectroscopy findings which are very rarely reported together so far.
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Affiliation(s)
- Demet Terek
- Division of Neonatology, Department of Pediatrics, Ege University Faculty of Medicine, Bornova, Izmir, Turkey.
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Cusmai R, Martinelli D, Moavero R, Dionisi Vici C, Vigevano F, Castana C, Elia M, Bernabei S, Bevivino E. Ketogenic diet in early myoclonic encephalopathy due to non ketotic hyperglycinemia. Eur J Paediatr Neurol 2012; 16:509-13. [PMID: 22261077 DOI: 10.1016/j.ejpn.2011.12.015] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/19/2011] [Revised: 12/16/2011] [Accepted: 12/22/2011] [Indexed: 10/14/2022]
Abstract
Non ketotic hyperglycinemia is a rare inborn error of glycine metabolism due to deficient activity of glycine cleavage system, a multienzymatic complex consisting of four protein subunits: the P-protein, the H-protein, the T-protein and the L-protein. The neonatal form of non ketotic hyperglycinemia presents in the first days of life with encephalopathy, seizures, multifocal myoclonus and characteristic "hiccups". Rapid progression may lead to intractable seizures, coma and respiratory failure requiring mechanical ventilation. Clinical trial with scavenges drugs decreasing glycine levels such as sodium benzoate, and with drugs reducing NMDA receptors excitatory properties, such as ketamine and dextromethorphan, have been tried but the outcome is usually poor; antiepileptic therapy, moreover, is unable to control epileptic seizures. Ketogenic diet has been successfully tried for refractory epilepsy in pediatric patients. We report three cases affected by neonatal non ketotic hyperglycinemia and early myoclonic encephalopathy treated with ketogenic diet. In our patients ketogenic diet, in association with standard pharmacological therapy, determined dramatic reduction of seizures and improved quality of life.
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Affiliation(s)
- Raffaella Cusmai
- Neurology Unit, "Bambino Gesù" Children's Hospital, IRCCS, Rome, Italy
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Chien YH, Lin MI, Weng WC, Du JC, Lee WT. Dextromethorphan in the treatment of early myoclonic encephalopathy evolving into migrating partial seizures in infancy. J Formos Med Assoc 2012; 111:290-4. [DOI: 10.1016/j.jfma.2012.03.007] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2009] [Revised: 03/31/2009] [Accepted: 10/02/2009] [Indexed: 10/28/2022] Open
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Griesmaier E, Keller M. Glutamate receptors — Prenatal insults, long-term consequences. Pharmacol Biochem Behav 2012; 100:835-40. [DOI: 10.1016/j.pbb.2011.04.011] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/20/2010] [Revised: 03/23/2011] [Accepted: 04/15/2011] [Indexed: 10/18/2022]
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Ficicioglu C, Bearden D. Isolated neonatal seizures: when to suspect inborn errors of metabolism. Pediatr Neurol 2011; 45:283-91. [PMID: 22000307 DOI: 10.1016/j.pediatrneurol.2011.07.006] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/09/2011] [Accepted: 07/25/2011] [Indexed: 10/16/2022]
Abstract
Neonatal seizures are common, and often comprise the first clinical indicator of central nervous system dysfunction. Although most neonatal seizures are secondary to processes such as hypoxic-ischemic injury, infection, or cortical malformations (which are readily identifiable through routine testing and imaging), seizures secondary to inborn errors of metabolism can be much more difficult to diagnose, and thus a high index of suspicion is required. The early diagnosis of inborn errors of metabolism is crucial, considering that many can receive effective treatment (e.g., dietary supplementation or restriction) with favorable long-term outcomes. This review emphasizes the importance of considering inborn errors of metabolism in the differential diagnosis of neonatal seizures, discusses red flags for inborn errors of metabolism as a cause of neonatal seizures, and provides an overview of diagnoses and treatments of inborn errors of metabolism most commonly associated with neonatal seizures.
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Affiliation(s)
- Can Ficicioglu
- Department of Pediatrics, Children’s Hospital of Philadelphia, 3501 Civic Center Boulevard, Colket (CTRB), 9th Floor, Number 54, Philadelphia, PA 19104, USA.
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Lee WT. Disorders of amino acid metabolism associated with epilepsy. Brain Dev 2011; 33:745-52. [PMID: 21803516 DOI: 10.1016/j.braindev.2011.06.014] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/19/2011] [Revised: 06/29/2011] [Accepted: 06/30/2011] [Indexed: 10/18/2022]
Abstract
Seizures are a common presenting manifestation in children with disorders of amino acid metabolism. However, seizures may be very common in some specific diseases, but are rare in other diseases. In patients with classical maple syrup urine disease (MSUD), seizures commonly occur in the neonatal stage. But in intermittent or intermediate MSUD, seizures may develop in a later stage, or are uncommon. Patients with nonketotic hyperglycinemia often present with early myoclonic encephalopathy in the first weeks of life. However, in patients with atypical variants, seizures may be rare. In addition, patients with sulfite oxidase deficiency, serine deficiency, or GABA-related disorders may also present with different types of seizures. In monoamine biosynthesis disorders, seizures are rare, but paroxysmal dystonia is frequently misdiagnosed as seizures. Therefore, the incidence of seizures in disorders of amino acid metabolism is variable. Timely diagnosis and early treatment may improve the prognosis of these disorders.
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Affiliation(s)
- Wang-Tso Lee
- Department of Pediatrics, National Taiwan University Hospital, Taipei.
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Meyer S, Acquaviva C, Shamdeen MG, Haas D, Vianey-Saban C. A novel missense mutation in a neonate with nonketotic hyperglycinemia. Pediatr Neurol 2010; 43:363-7. [PMID: 20933183 DOI: 10.1016/j.pediatrneurol.2010.05.025] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/11/2010] [Revised: 04/15/2010] [Accepted: 05/24/2010] [Indexed: 11/19/2022]
Abstract
Nonketotic hyperglycinemia (OMIM #605899), also known as glycine encephalopathy, is an autosomal recessive disorder of glycine metabolism caused by a defect in the glycine cleavage system. A term neonate developed progressive lethargy, muscular hypotonia, and respiratory insufficiency on day 2 after birth, but no overt clinical seizures. Amplitude-integrated electroencephalography indicated a continuous burst-suppression pattern. The diagnosis of nonketotic hyperglycinemia was made biochemically and was confirmed by genetic studies, which revealed two missense mutations (one not previously described) within the glycine decarboxylase gene, GLDC. Nonketotic hyperglycinemia should be incorporated into the differential diagnosis of neonatal hypotonia, to avoid an erroneous diagnosis of sepsis or hypoxic ischemic injury. Amplitude-integrated electroencephalography may be helpful in the initial assessment of severely sick and hypotonic neonates without overt clinical seizures, and may direct further diagnostic evaluation.
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Affiliation(s)
- Sascha Meyer
- Department of Pediatric and Neonatal Intensive Care Medicine, University Hospital of Saarland, Homburg, Germany.
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Rossi S, Daniele I, Bastrenta P, Mastrangelo M, Lista G. Early myoclonic encephalopathy and nonketotic hyperglycinemia. Pediatr Neurol 2009; 41:371-4. [PMID: 19818941 DOI: 10.1016/j.pediatrneurol.2009.05.005] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/08/2009] [Revised: 04/27/2009] [Accepted: 05/04/2009] [Indexed: 11/29/2022]
Abstract
Early myoclonic encephalopathy is an epileptic syndrome with different etiologies. Nonketotic hyperglycinemia is one cause. We describe two cases of early myoclonic encephalopathy, secondary to nonketotic hyperglycinemia, with fatal evolution in the neonatal period. These two cases may better clarify clinical findings that can be associated with impairment of glycine metabolism. Distinguishing features include agenesis of the corpus callosum in patient 1, and weight loss exceeding 10%, associated with metabolic acidosis, in patient 2. The burst-suppression electroencephalography pattern is relatively common in neonatal encephalopathies, and is frequently associated with seizures. Nonketotic hyperglycinemia is an inborn error of metabolism caused by mutations in genes encoding protein in the mitochondrial glycine cleavage system. The neonatal form is a severe, frequently lethal neurologic disease. When associated with electro-clinical features, progressive lethargy and hypotonia occur in the first days of life, progressing to apnea and often death. Prospective treatment with oral sodium benzoate, the N-methyl-d-aspartate receptor antagonist ketamine, and dextromethorphan can favorably modify the early neonatal course of severe nonketotic hyperglycinemia, but does not prevent poor long-term outcomes.
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Affiliation(s)
- Samantha Rossi
- Neonatal Intensive Care Unit, Istituti Clinici di Perfezionamento, Milan, Italy.
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Griesmaier E, Keller M. Neuroprotective strategies in excitotoxic brain injury: potential applications to the preterm brain. FUTURE NEUROLOGY 2009. [DOI: 10.2217/fnl.09.28] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Neuronal and oligodendroglial cell death owing to increased glutamate levels plays an important role in the pathophysiology of hypoxic-, ischemic- and inflammation-mediated brain injury as well as in disorders such as epilepsy, Alzheimer’s, Parkinson’s or Huntington’s disease. In addition, excitotoxic brain injury is known to be a major contributing factor to brain injury in preterm infants. Excitotoxicity is characterized as excessive glutamatergic activation of postsynaptic receptors that consequently leads to cell injury and cell death. The major excitatory amino acid neurotransmitter is glutamate. Glutamate plays a key role in brain development, affecting progenitor cell differentiation, proliferation, migration and survival. In physiological conditions the presence of glutamate in the synapse is regulated by ATP-dependent glutamate transporters in neurons and glial cells, with astrocytes being responsible for a major part of glutamate uptake in the brain. In pathologic circumstances the function of the transporters is impaired, leading to glutamate accumulation in the synaptic cleft and in turn excessive activation of postsynaptic glutamate receptors with subsequent massive Ca2+ influx, activation of neuronal nitric oxide synthase, translocation of proapoptotic genes to the mitochondria, mitochondrial dysfunction, release of cytochrome C into the cytosol, activation of caspases and subsequent cell death. Based on the pathogenic concept of an overactivation of the excitatory pathways, glutamate receptors have been a longstanding therapeutic target for rational drug design. This article reviews the pathophysiology of excitotoxic brain injury in the example of preterm brain injury, as well as current research on therapeutic antiexcitotoxic strategies.
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Affiliation(s)
- Elke Griesmaier
- Department of Pediatrics IV, Medical University Innsbruck, Austria, Anichstr. 35, 6020 Innsbruck, Austria
| | - Matthias Keller
- Department of Pediatrics I University Hospital Essen, Hufelandstraße 55, 45147 Essen Germany
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Keller M, Griesmaier E, Auer M, Schlager G, Urbanek M, Simbruner G, Gressens P, Sárközy G. Dextromethorphan is protective against sensitized N-methyl-d-aspartate receptor-mediated excitotoxic brain damage in the developing mouse brain. Eur J Neurosci 2008; 27:874-83. [DOI: 10.1111/j.1460-9568.2008.06062.x] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Abstract
Nonketotic hyperglycinemia has variable phenotypic expressions and a poor prognosis. We report a case of severe neonatal nonketotic hyperglycinemia, who started convulsing immediately after birth. His glycine index was 0.38 and he did not respond to treatment with sodium benzoate and dextromethorphan. Hypotonia, transient hyperammonemia and metabolic acidosis were associated findings.
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Affiliation(s)
- Rahul P Bhamkar
- Department of Pediatrics, MGM Medical College and Hospital, Navi, Mumbai, India
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Abstract
The pediatric neurotransmitter disorders represent an enlarging group of neurological syndromes characterized by abnormalities of neurotransmitter synthesis and breakdown. The disorders of dopamine and serotonin synthesis are aromatic amino acid decarboxylase deficiency, tyrosine hydroxylase deficiency, and disorders of tetrahydrobiopterin synthesis. Amino acid decarboxylase, tyrosine hydroxylase, sepiapterin reductase, and guanosine triphosphate cyclohydrolase (Segawa disease) deficiencies do not feature elevated serum phenylalanine and require cerebrospinal fluid analysis for diagnosis. Segawa disease is characterized by dramatic and lifelong responsiveness to levodopa. Glycine encephalopathy is typically manifested by refractory neonatal seizures secondary to a defect of the glycine degradative pathway. gamma-amino butyric acid (GABA) metabolism is associated with several disorders, including glutamic acid decarboxylase deficiency with nonsyndromic cleft lip/ palate, GABA-transaminase deficiency, and succinic semialdehyde dehydrogenase deficiency. The latter is characterized by elevated gamma-hydroxybutyric acid and includes a wide range of neuropsychiatric symptoms as well as epilepsy. Pyridoxine-dependent seizures have now been associated with deficiency of alpha-aminoadipic semialdehyde dehydrogenase, as well as a new variant requiring therapy with pyridoxal-5-phosphate, the biologically active form of pyridoxine.
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Affiliation(s)
- Phillip L Pearl
- Department of Neurology, Children's National Medical Center, The George Washington University School of Medicine, Washington, DC 20010, USA.
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Pearl PL, Hartka TR, Taylor J. Diagnosis and treatment of neurotransmitter disorders. Curr Treat Options Neurol 2006; 8:441-50. [PMID: 17032564 DOI: 10.1007/s11940-006-0033-7] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
The neurotransmitter disorders represent an enigmatic and enlarging group of neurometabolic conditions caused by abnormal neurotransmitter metabolism or transport. A high index of clinical suspicion is important, given the availability of therapeutic strategies. This article covers disorders of monoamine (catecholamine and serotonin) synthesis, glycine catabolism, pyridoxine dependency, and gamma-aminobutyric acid (GABA) metabolism. The technological aspects of appropriate cerebrospinal fluid (CSF) collection, shipment, study, and interpretation merit special consideration. Diagnosis of disorders of monoamines requires analysis of CSF homovanillic acid, 5-hydroxyindoleacetic acid, ortho-methyldopa, BH4, and neopterin. The delineation of new disorders with important therapeutic implications, such as cerebral folate deficiency and PNPO deficiency, serves to highlight the value of measuring CSF neurotransmitter precursors and metabolites. The impressive responsiveness of Segawa fluctuating dystonia to levodopa is a hallmark feature of previously unrecognized neurologic morbidity becoming treatable at any age. Aromatic amino acid decarboxylase and tyrosine hydroxylase deficiency have more severe phenotypes and show variable responsiveness to levodopa. Glycine encephalopathy usually has a poor outcome; benzoate therapy may be helpful in less affected cases. Pyridoxine-dependent seizures are a refractory but treatable group of neonatal and infantile seizures; rare cases require pyridoxal-5-phosphate. Succinic semialdehyde dehydrogenase deficiency is relatively common in comparison to the remainder of this group of disorders. Treatment directed at the metabolic defect with vigabatrin has been disappointing, and multiple therapies are targeted toward specific but protean symptoms. Other disorders of GABA metabolism, as is true of the wide spectrum of neurotransmitter disorders, will require increasing use of CSF analysis for diagnosis, and ultimately, treatment.
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Affiliation(s)
- Phillip L Pearl
- Department of Neurology, Children’s National Medical Center, Washington, DC 20010, USA.
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Morrison PF, Sankar R, Shields WD. Valproate-induced chorea and encephalopathy in atypical nonketotic hyperglycinemia. Pediatr Neurol 2006; 35:356-8. [PMID: 17074608 DOI: 10.1016/j.pediatrneurol.2006.06.009] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/27/2006] [Revised: 03/06/2006] [Accepted: 06/05/2006] [Indexed: 11/21/2022]
Abstract
Nonketotic hyperglycinemia is a disorder of amino acid metabolism in which a defect in the glycine cleavage system leads to an accumulation of glycine in the brain and other body compartments. In the classical form it presents as neonatal apnea, intractable seizures, and hypotonia, followed by significant psychomotor retardation. An important subset of children with nonketotic hyperglycinemia are atypical variants who present in a heterogeneous manner. This report describes a patient with mild language delay and mental retardation, who was found to have nonketotic hyperglycinemia following her presentation with acute encephalopathy and chorea shortly after initiation of valproate therapy.
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Affiliation(s)
- Peter F Morrison
- Department of Pediatrics, Division of Pediatric Neurology, David Geffen School of Medicine at UCLA, Los Angeles, CA 90095, USA.
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Korman SH, Wexler ID, Gutman A, Rolland MO, Kanno J, Kure S. Treatment from birth of nonketotic hyperglycinemia due to a novel GLDC mutation. Ann Neurol 2006; 59:411-5. [PMID: 16404748 DOI: 10.1002/ana.20759] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
OBJECTIVE To determine whether the devastating outcome of neonatal-onset glycine encephalopathy (NKH) could be improved by instituting treatment immediately at birth rather than after symptoms are already well established. METHODS A newborn with NKH diagnosed prenatally following the neonatal death of a previous affected sibling was treated from birth with oral sodium benzoate (250 mg/kg/day) and the NMDA receptor antagonist ketamine (15 mg/kg/day) immediately after sampling cord blood and cerebrospinal fluid (CSF) for glycine determination. Glycine cleavage system (CGS) activity was determined in placental tissue. Mutation analysis was performed by sequencing all GLDC, GCSH and AMT exons. RESULTS CSF glycine (99 micromol/L, reference 3.8-8.0) was already markedly elevated at birth. GCS activity in placental tissue was severely reduced (2.6% of controls). A novel homozygous GLDC c.482A-->G(Y161C) missense mutation was identified. Neonatal hypotonia and apnea did not occur but the long-term outcome was poor, with intractable seizures and severe psychomotor retardation. This contrasts with the favorable outcome with early treatment in variant NKH with mild GCS deficiency (Ann Neuol 2004;56:139-143). INTERPRETATION Prospective treatment with this regimen can favorably modify the early neonatal course of severe NKH but does not prevent the poor long-term outcome, suggesting glycine-induced prenatal injury and/or ongoing postnatal damage.
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Affiliation(s)
- Stanley H Korman
- Department of Clinical Biochemistry, Mt. Scopus, Hadassah-Hebrew University Medical Center, Jerusalem, Israel.
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Abstract
Diagnosis and management of pediatric epilepsy are challenging for a variety of reasons; however, one of the most common yet difficult situations involves treatment of the patient with pediatric epilepsy with coexistent cognitive impairment or psychiatric disturbance. The etiologies and presentations of these comorbidities are myriad, making diagnosis problematic; furthermore, interactions between epilepsy and its treatments and the neuropsychiatric problem and its treatments add another layer of complexity to the management of these patients. Antiepileptic drugs are often blamed for cognitive or behavioral problems in children treated for epilepsy, but the actual contribution to such problems in a particular child can be difficult to ascertain.
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Affiliation(s)
- John M Pellock
- Division of Child Neurology, Department of Neurology, Virginia Commonwealth University, Medical College of Virginia, 1001 East Marshall Street, 1st Floor, Richmond, VA 23298, USA.
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Affiliation(s)
- John M Pellock
- Division of Child Neurology, Department of Neurology, Virginia Commonwealth University, Medical College of Virginia, 1001 East Marshall Street, 1st Floor, Richmond, VA 23298, USA.
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