Manejo anestésico y perioperatorio en paciente pediátrico con hiperglicinemia no cetósica / Anesthetic and perioperative management in children with non-ketotic hyperglycinemiawith non-ketotic hyperglycinemia

Presentación del caso: se reporta un paciente pediátrico con diagnóstico de hiperglicinemia no cetósica (HNC), enfermedad neurometabólica poco frecuente ocasionada por una deficiencia en el sistema de segmentación de la glicina, codificada por los genes GLDC, GCSH, AMT y GCSL que conduce a niveles elevados de glicina en la sinapsis generando un efecto agonista prolongado en los receptores N-metil-D-aspartato (NMDA). Discusión y conclusiones: se asocia con hipotonía, convulsiones y trastornos de la deglución, los cuales dependerán de la edad de presentación. Se revisa la literatura actual para el abordaje perioperatorio.

Case presentation: we report a child with a diagnosis of non-ketotic hyperglycinemia (NKGH), a rare neurometabolic disease caused by a defect in the glycine cleavage system, encoded by the GLDC, GCSH, AMT and GCSL genes resulting in elevated synaptic glycine levels generating a prolonged agonist effect on N-methyl-D-aspartate (NMDA) receptors. Discussion and conclusions: it is associated with hypotonia, seizures and swallowing disorders, which will depend on the age at presentation. A literature review was conducted to tailor perioperative approach.

Hiperglicinemia no cetósica neonatal, fenotipo atenuado / Neonatal nonketotic hyperglycinemia, attenuated phenotype / Hiperglicinemia não-cetótica neonatal, fenótipo atenuado

Introducción. La Hiperglicinemia no Cetósica (HNC) es un error innato del metabolismo de herencia autosómica recesiva, cuya principal característica es la acumulación de glicina en los fluidos corporales, producido por una falla en el complejo de clivaje enzimático de este aminoácido. Presentación del caso. Presentamos el caso de un recién nacido de 36 semanas, con adaptación neonatal espontánea, sin historia de noxa perinatal ni hipoglicemia documentada, quien tras un corto período de 24 horas presentó deterioro neurológico progresivo, rápida alteración del estado de conciencia hasta el coma y falla ventilatoria. Llamó la atención al ingreso la hipotonía severa generalizada, hiporreflexia, ausencia de reflejos primitivos, con episodios de hipo aislado y movimientos oculares anormales. Ante la sospecha de un error innato del metabolismo se realizó el perfil de aminoácidos donde se evidenció elevación significativa de la glicina, 1417 mmol/L (referencia 94-553 umol/L). Se solicitaron aminoácidos en líquido cefalorraquídeo, glicina muy elevada 1263 mmol/L (referencia 3-7 umol/L), con lo que se confirma la sospecha de hiperglicinemia no cetósica. Se decidió iniciar manejo con benzoato de sodio y dextrometorfano. La resonancia magnética inicial fue normal, en estudio control se encontraron al igual que en el electroencefalograma hallazgos reportados previamente en la literatura para esta patología. Discusión. La mayoría de los niños con HNC se presentan en el período neonatal o en la primera infancia, y solo los casos más leves se presentan al final de la infancia o la niñez. En las presentaciones de inicio neonatal, el 85% tiene HNC grave y el 15% tiene forma atenuada, como este caso. El diagnóstico de la HNC se hace con base en la sospecha clínica, confirmada por los hallazgos de laboratorio, con la alteración característica de la glicina tanto en plasma como en el LCR y soportada por los hallazgos de las neuroimágenes y electroencefalograma (EEG). Conclusiones. La HNC no es una condición tan inusual, aunque sí posiblemente subdiagnosticada por la forma de presentación tan catastrófica, además porque no produce grandes desarreglos metabólicos de rápido diagnóstico. Por este motivo, ante un paciente con cuadro clínico sugestivo, con coma, alteración respiratoria y convulsiones de difícil manejo, y muy característicamente hipo, debe solicitarse el estudio de aminoácidos en plasma, neuroimágenes y EEG, con el fin de instaurar un manejo temprano.

Introduction. Nonketotic hyperglycinemia (NKH) is an autosomal recessive innate error of metabolism, whose main characteristic is the accumulation of glycine in body fluids, produced by a failure in the enzymatic cleavage complex of this amino acid. Case Presentation. We present the case of a 36-week-old newborn, with spontaneous neonatal adaptation, no history of perinatal noxa or documented hypoglycemia, who after a short period of 24 hours presented progressive neurological deterioration, rapid alteration of consciousness to coma and ventilatory failure. At admission the patient was noted for severe generalized hypotonia, hyporeflexia, absence of primitive reflexes, with episodes of isolated hiccups and abnormal eye movements. In view of the suspicion of an innate error of metabolism, an amino acid profile was performed, showing a significant elevation of glycine, 1417 umol/L (reference 94-553 umol/L). Amino acids were requested in cerebrospinal fluid, glycine very elevated 1263 umol/L (reference 3-7 umol/L), confirming the suspicion of nonketotic hyperglycinemia. It was decided to start treatment with sodium benzoate and dextromethorphan. The initial MRI was normal; in the control study, findings previously reported in the literature for this pathology were found, as well as in the electroencephalogram. Discussion. Most children with NKH will display it in the neonatal period or early infancy, with only the mildest cases presenting in late infancy or childhood. In neonatal-onset cases, 85% have severe NKH and 15% have attenuated form, as in this case. The diagnosis of NKH is made based on clinical suspicion, confirmed by laboratory findings, with the characteristic alteration of glycine in both plasma and CSF and supported by neuroimaging and electroencephalogram (EEG) findings. Conclusions. NKH is not such an unusual condition, although it is possibly underdiagnosed because of its catastrophic presentation and because it does not produce major metabolic disorders that are quickly diagnosed. For this reason, in a patient with a suggestive clinical condition, with coma, respiratory alteration and unmanageable seizures, and very characteristically hiccups, the study of amino acids in plasma, neuroimaging and EEG should be requested, in order to establish early treatment.

Introdução. A hiperglicinemia não-cetótica (HNC) é um erro inato do metabolismo de herança autossômica recessiva, cuja principal característica é o acúmulo de glicina nos fluidos corporais, produzido por uma falha no complexo de clivagem enzimática deste aminoácido. Apresentação do caso. Apresentamos o caso de um recém-nascido de 36 semanas, com adaptação neonatal espontânea, sem história de noxa perinatal nem hipoglicemia documentada, que após um curto período de 24 horas apresentou deterioração neurológica progressiva, alteração rápida de consciência até coma e falha ventilatória. Na admissão, eram notáveis a hipotonia grave generalizada, hiporreflexia, ausência de reflexos primitivos, com episódios de soluços isolados e movimentos oculares anormais. Diante da suspeita de erro inato no metabolismo, foi realizado o perfil de aminoácidos, onde foi constatada elevação significativa da glicina, 1417umol/L (referência 94-553 umol/L). Foram solicitados aminoácidos no líquido cefalorraquidiano, glicina muito alta 1263umol/L (referência 3-7 umol/L), confirmando a suspeita de hiperglicinemia não-cetótica. Foi decidido iniciar o tratamento com benzoato de sódio e dextrometorfano. A ressonância magnética inicial foi normal, tanto em estudo controle quanto no eletroencefalograma, foram encontrados achados previamente relatados na literatura para esta patologia. Discussão. A maioria das crianças com HNC estão no período neonatal ou na primeira infância, e apenas os casos mais leves ocorrem na infância ou na infância tardia. Nas apresentações de início neonatal, 85% têm HNC grave e 15% têm forma atenuada, como neste caso. O diagnóstico de HNC é feito com base na suspeita clínica, confirmada por achados laboratoriais, com alteração característica da glicina tanto no plasma quanto no LCR e apoiado por achados de neuroimagem e eletroencefalograma (EEG). Conclusões. A HNC não é uma condição tão incomum, embora possivelmente seja subdiagnosticada por sua apresentação catastrófica, também por não produzir grandes distúrbios metabólicos que possam ser diagnosticados rapidamente. Por esse motivo, em um paciente com quadro clínico sugestivo, com coma, distúrbios respiratórios e convulsões de difícil manejo, e soluços muito característicos, deve ser solicitado um estudo de aminoácidos no plasma, neuroimagem e EEG a fim de estabelecer um tratamento rápido.

Distúrbio de movimento por conta de estado hiperosmolar não cetótico em idosa: relato de caso / Movement disorder caused by hyperosmolar hyperglycemic state in an older adult: a case report

O diabetes e suas complicações constituem as principais causas de mortalidade precoce na maioria dos países. O envelhecimento da população e a crescente prevalência da obesidade e do sedentarismo, além dos processos de urbanização, são considerados os principais fatores responsáveis pelo aumento da incidência e da prevalência do diabetes mellitus (DM) em todo o mundo. Este relato de caso objetiva descrever a presença de distúrbio do movimento em idoso por conta do estado hiperosmolar não cetótico. A combinação de hemicoreia-hemibalismo, hiperglicemia não cetótica e envolvimento dos gânglios da base em exames de imagem é considerada uma síndrome única. Os distúrbios do movimento em estado hiperosmolar não cetótico apresentam resposta terapêutica satisfatória com o uso de neurolépticos e controle glicêmico adequado. A escassez de trabalhos publicados proporciona subdiagnósticos clínico e laboratorial, interferindo no prognóstico e no acompanhamento dos pacientes.

Diabetes mellitus (DM) and its complications constitute the leading causes of early mortality in most countries. Population aging and the growing prevalence of obesity and sedentary lifestyles, in addition to spreading urbanization, are considered the main drivers of the increasing incidence and prevalence of DM worldwide. This case report describes the acute onset of movement disorder in an older woman secondary to hyperosmolar hyperglycemic state (HHS). The combination of hemichorea­hemiballismus, HHS, and evidence of basal ganglia involvement on neuroimaging is considered a unique syndrome. Movement disorders secondary to HHS respond satisfactorily to administration of neuroleptic agents and proper glycemic control. The lack of published studies on this pathologic entity may lead to clinical and laboratory underdiagnosis, with negative impacts on patient prognosis and follow-up.

Dos mutaciones novedosas en el gen de glicina descarboxilasa en un niño con hiperglicinemia no cetósica clásica: a propósito de un caso / Two novel mutations in the glycine decarboxylase gene in a boy with classic nonketotic hyperglycinemia: case report

La hiperglicinemia no cetósica es una encefalopatía por glicina autosómica recesiva y hereditaria sumamente rara, causada por una deficiencia en el sistema enzimatico de división de la glicina mitocondrial, que provoca síntomas clínicos graves. La hiperglicinemia no cetósica se caracteriza por fenotipos diversos y complejos, por ejemplo, hipotonía, convulsiones, deterioro cognitivo, retrasos del desarrollo y espasmos mioclónicos que podrían causar apnea e incluso la muerte. En este artículo, presentamos el caso de un niño de 1 año con convulsiones mioclónicas, hipotonía y coma, con aumento de la concentración de glicina en el plasma y el líquido cefalorraquídeo y con un índice de glicina en líquido cefalorraquídeo/plasma de 0,24. Existen dos mutaciones heterocigotas novedosas que confirman el diagnóstico de hiperglicinemia no cetósica. Una es una mutación de aminoácido, c.2516A>G (p.Y839C), y la otra es una mutación en los sitios de corte y empalme, c.2457+2T>A, en el gen GLDC.

Nonketotic hyperglycinemia is an extremely rare autosomal recessively inherited glycine encephalopathy caused by a deficiency in the mitochondrial glycine cleavage system, which leads to severe clinical symptoms. Nonketotic hyperglycinemia is characterized by complex and diverse phenotypes, such as hypotonia, seizures, cognitive impairment, developmental delays and myoclonic jerks that may lead to apnea and even death. Here we report a 1-year-old boy with myoclonic seizures, hypotonia and coma; he had elevated plasma and cerebrospinal fluid glycine levels, and cerebrospinal fluid/plasma glycine ratio was 0.24. Two novel heterozygous mutations confirm the diagnosis of nonketotic hyperglycinemia. One is a missense mutation c.2516A>G (p.Y839C) and the other one is a splicing mutation c.2457+2T>A in the GLDC gene.

Clinical and genetic analyses of a family with atypical nonketotic hyperglycinemia caused by compound heterozygous mutations in the GLDC gene / 中国当代儿科杂志

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.

Clinical and molecular genetic study of nonketotic hyperglycinemia in a Chinese family / 中国当代儿科杂志

Nonketotic hyperglycinemia (NKH) is a rare, inborn error of metabolism. In this case report, a Chinese male infant was diagnosed with NKH caused by GLDC gene mutation. The clinical characteristics and genetic diagnosis were reported. The infant presented with an onset of early metabolic encephalopathy and Ohtahara syndrome. Both blood and urinary levels of metabolites were in the normal range. Brain MRI images indicated a poor development of corpus callosum, and a burst suppression pattern was found in the EEG. Results of target gene sequencing technology combined with multiplex ligation-dependent probe amplification (MLPA) indicated a heterozygous missense mutation of c.1786 C>T (p.R596X) in maternal exon 15 and a loss of heterozygosity of 4-15 exon gross deletions in paternal GLDC gene. These definite pathogenic mutations confirmed the diagnosis of NKH. The infant's clinical condition was not improved after treatment with adreno-cortico-tropic-hormone, topiramate and dextromethorphan, and he finally died at 4 months of age. Patients with NKH often exhibit complicated clinical phenotypes and are lack of specific symptoms. NKH could be diagnosed by metabolic screening and molecular genetic analysis.

Hiperglicinemia no cetósica: mutación novedosa en el gen aminometiltransferasa. A propósito de un caso / Nonketotic hyperglycinemia: novel mutation in the aminomethyl transferase gene. Case report

La hiperglicinemia no cetósica es un raro trastorno metabólico autosómico recesivo hereditario causado por una deficiencia en el sistema enzimático de división de la glicina mitocondrial. Se desconoce la incidencia general de la hiperglicinemia no cetósica, aunque es mayor en ciertas poblaciones, como las del norte de Finlandia (1/12 000) y de la Columbia Británica (1/63 000). Se sabe que son tres los genes que causan hiper-glicinemia no cetósica: GLDC, AMT y GCSH. Las mutaciones en el gen AMT son responsables del 20% de los casos de hiperglicinemia no cetósica. En este artículo describimos una mutación novedosa del codón de terminación (c.565C>T, p.Q189*) del gen AMT en un niño de cuatro meses de vida con hiperglicinemia no cetósica.

Nonketotic hyperglycinemia is a rare autosomal recessively inherited metabolic disorder, caused by a deficiency in the mitochondrial glycine cleavage system. The overall incidence of nonketotic hyperglycinemia is unknown, but is higher in certain populations such as north Finland (1/12,000) and British Colombia (1/63,000). Three genes (GLDC, AMT and GCSH) are known to cause nonketotic hyperglycinemia. Mutations in the AMT gene are responsible for 20% of nonketotic hyperglycinemia cases. We describe a novel stop codon mutation (c.565C>T, p.Q189*) in AMT gene in a four-month male infant with nonketotic hyperglycinemia.

Biochemical findings in the first Filipino child confirmed to have nonketotic hyperglycinemia: A case report

@#<p style="text-align: justify;">This is a report of the biochemical findings in the first diagnosed case of Nonketotic Hyperglycinemia (NKH) in the Philippines. Urine metabolic screening by high voltage electrophoresis showing grossly increased glycine necessitated  confirmation of NKH. Confirmatory analysis was done by paired plasma-cerebrospinal fluid quantitative amino acid analysis using Ultrahigh Performance Liquid Chromatography (UPLC). The result was compatible with the clinical picture of the patient who presented primarily with apnea, seizures, hypotonia and lethargy. This paper emphasizes the importance of locally available biochemical genetic tests in the diagnosis of inborn errors of metabolism.</p>

A novel association between cerebral sinovenous thrombosis and nonketotic hyperglycinemia in a neonate / 소아과

Lethargy in newborns usually indicates central nervous system dysfunction, and many conditions such as cerebrovascular events, infections, and metabolic diseases should be considered in the differential diagnosis. Nonketotic hyperglycinemia is an autosomal recessive error of glycine metabolism, characterized by myoclonic jerks, hypotonia, hiccups, apnea, and progressive lethargy that may progress to encephalopathy or even death. Cerebral sinovenous thrombosis is a rare condition with various clinical presentations such as seizures, cerebral edema, lethargy, and encephalopathy. Here, we report the case of a newborn infant who presented with progressive lethargy. An initial diagnosis of cerebral venous sinus thrombosis was followed by confirmation of the presence of nonketotic hyperglycinemia.

Revisão sobre cetoacidose diabética / Review on diabetic ketoacidose

Este trabalho visa a esclarecer o manejo da cetoacidose diabética, facilitando o diagnóstico e tratamento desta emergência endocrinológica, a fim de diminuir as complicações e melhorar o desfecho clínico do paciente.

This paper intended to clarify the management of the diabetic ketoacidosis, an endocrinological emergency , by facilitating its diagnosis and treatment, in order to reduce complications and improve the clinical outcome of the patient.

Sequential magnetic resonance spectroscopic changes in a patient with nonketotic hyperglycinemia / 소아과

Nonketotic hyperglycinemia (NKH) is a rare inborn error of amino acid metabolism. A defect in the glycine cleavage enzyme system results in highly elevated concentrations of glycine in the plasma, urine, cerebrospinal fluid, and brain, resulting in glycine-induced encephalopathy and neuropathy. The prevalence of NKH in Korea is very low, and no reports of surviving patients are available, given the scarcity and poor prognosis of this disease. In the current study, we present a patient with NKH diagnosed on the basis of clinical features, biochemical profiles, and genetic analysis. Magnetic resonance spectroscopy (MRS) allowed the measurement of absolute glycine concentrations in different parts of the brain that showed a significantly increased glycine peak, consolidating the diagnosis of NKH. In additional, serial MRS follow-up showed changes in the glycine/creatinine ratios in different parts of the brain. In conclusion, MRS is an effective, noninvasive diagnostic tool for NKH that can be used to distinguish this disease from other glycine metabolism disorders. It may also be useful for monitoring NKH treatment.

Hiperglicinemia no cetósica neonatal: presentación de caso / Non-ketotic neonatal hyperglycinemia: case report

La hiperglicinemia no cetósica es un error innato del metabolismo del aminoácido glicina. Es una entidad rara que se manifiesta de manera clásica en el período neonatal con convulsiones intratables y apneas que requieren asistencia ventilatoria prolongada. Se presenta el caso de un lactante de 2 meses de edad con deterioro neurológico desde el tercer día de vida y convulsiones. Se describen los hallazgos en imágenes por resonancia magnética y espectroscopia por resonancia magnética.

Early myoclonic encephalopathy.

Early myoclonic encephalopathy (EME) is a rare malignant epileptic syndrome. The erratic myoclonus with or without focal motor seizures, onset before 3 months of age, and persistent suppression-burst pattern in electroencephalograph (EEG) are accepted as the diagnostic criteria for EME. We report an 11 month-old infant with EME which was secondary to non-ketotic hyperglycinemia.

Neonatal nonketotic hyperglycinemia.

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.

Uncommon Neurological Presentation due to Non-Ketotic Hyperglycemia (NKH) –Report to two cases.

Two patients of uncommon neurological presentation due to non-ketotic hyperglycemia (NKH) are being described in this report. Generalized choreo-athetosis and epilepsia partialis continua as presenting symptoms in non-ketotic hyperglycemia is rare. The abnormal movements responded completely to insulin therapy. In acute onset of abnormal movements, besides other causes, metabolic disorders such as non-ketotic hyperglycemia should also be ruled out as they are treatable.

Diabetic nonketotic hyperosmolar state: interesting imaging observations in 2 patients with involuntary movements and seizures.

We report two patients of diabetic nonketotic hyperosmolar state presenting acutely with "self-limiting hemichorea - hemiballismus" and "generalized convulsive status epilepticus". CT scan in both the patients revealed a hyperdense nonenhancing basal ganglia. Magnetic resonance imaging brain of patient 1 showed it to be hyperintense on T1W image and iso-hyper intense on T2W image, minimally enhancing with contrast injection.

Tonic eye deviation due to nonketotic hyperglycaemia induced focal seizures: case report.

We report a case of intermittent tonic conjugate eye deviation due to nonketotic hyperglycaemia induced focal seizure.

Nonketotic hyperglycinemia in two siblings with neonatal seizures.

Seizures are a common problem in neonates. Differential diagnoses include infection, trauma, hypoxia and congenital metabolic disorders. Among these, congenital metabolic disorder is less familiar to general pediatricians. We report two patients with nonketotic hyperglycinemia (NKH), a rare and lethal congenital metabolic disease. Transient hyperammonemia and transient hypouricemia, uncommon features found in NKH, were detected in one patient. High doses of sodium benzoate and dextromethorphan failed to modify the clinical course. Neuropathology denoted characteristic diffuse vacuolization and changes in reactive and gliotic astrocytes. The clinical course, biochemical findings, diagnostic approaches and diagnostic tests are discussed in detail. Recent modalities of treatment are reviewed. Because of its rarity and rapidly progressive course, it maybe underdiagnosed resulting in death before being recognized. Awareness of the possibility of congenital metabolic disorder in early neonatal catastrophe will increase the diagnostic rate.

Localized Proton MR Spectroscopic Detection of Nonketotic Hyperglycinemia in an Infant

Nonketotic hyperglycinemia (NKH) is a rare metabolic brain disease caused by deficient activity of the glycine cleveage system. Localized proton MR spectroscopy (echo-time 166 msec), performed in an infant with the typical clinical and biochemical features of neonatal NKH, showed a markedly increased peak intensity at 3.55 ppm, which was assigned to glycine. Serial proton MR spectrosocpic studies indicated that glycine/choline and glycine/total creatine ratios correlated closely with the patient's clinical course. Proton MR spectroscopy was useful for the non-invasive detection and monitoring of cerebral glycine levels in this infant with NKH.