Are sodium-glucose cotransporter-2 inhibitors safe adjunctive drugs during insulin therapy in young children with type 1 diabetes? The first case of type 1 diabetes with SLC5A2 mutation.

Highlights A persistent glycosuria alongside hypoglycemia in pediatric type 1 diabetes mellitus needs further evaluation. Morning hypoglycemia is a limiting side effect of sodium glucose transporter 2 (SGLT2) inhibitors in children younger than 5 years old. SLC5A2 mutation functioning as a SGLT2 inhibitor can result in acceptable range of glycated hemoglobin in younger children and lower required doses of insulin.

Glucose transporter-2 regulation of VMN GABA neuron metabolic sensor and transmitter gene expression.

Glucose transporter-2 (GLUT2) monitors cellular glucose uptake. Astrocyte GLUT2 controls glucose counterregulatory hormone secretion. In vivo gene silencing and laser-catapult-microdissection tools were used here to investigate whether ventromedial hypothalamic nucleus (VMN) GLUT2 may regulate dorsomedial (VMNdm) and/or ventrolateral (VMNvl) γ-aminobutyric acid (GABA) neurotransmission to control this endocrine outflow in female rats. VMN GLUT2 gene knockdown suppressed or stimulated hypoglycemia-associated glutamate decarboxylase (GAD)1 and GAD2 mRNA expression in VMNdm versus VMNvl GABAergic neurons, respectively. GLUT2 siRNA pretreatment also modified co-expressed transmitter marker gene profiles in each cell population. VMNdm GABA neurons exhibited GLUT2 knockdown-sensitive up-regulated 5'-AMP-activated protein kinase-alpha1 (AMPKα1) and -alpha2 (AMPKα2) transcripts during hypoglycemia. Hypoglycemic augmentation of VMNvl GABA neuron AMPKα2 was refractory to GLUT2 siRNA. GLUT2 siRNA blunted (VMNdm) or exacerbated (VMNvl) hypoglycemic stimulation of GABAergic neuron steroidogenic factor-1 (SF-1) mRNA. Results infer that VMNdm and VMNvl GABA neurons may exhibit divergent, GLUT2-dependent GABA neurotransmission patterns in the hypoglycemic female rat. Data also document differential GLUT2 regulation of VMNdm versus VMNvl GABA nerve cell SF-1 gene expression. Evidence for intensification of hypoglycemic hypercorticosteronemia and -glucagonemia by GLUT2 siRNA infers that VMN GLUT2 function imposes an inhibitory tone on these hormone profiles in this sex.

Fetal Hypoglycemia Induced by Placental SLC2A3-RNA Interference Alters Fetal Pancreas Development and Transcriptome at Mid-Gestation.

Glucose, the primary energy substrate for fetal oxidative processes and growth, is transferred from maternal to fetal circulation down a concentration gradient by placental facilitative glucose transporters. In sheep, SLC2A1 and SLC2A3 are the primary transporters available in the placental epithelium, with SLC2A3 located on the maternal-facing apical trophoblast membrane and SLC2A1 located on the fetal-facing basolateral trophoblast membrane. We have previously reported that impaired placental SLC2A3 glucose transport resulted in smaller, hypoglycemic fetuses with reduced umbilical artery insulin and glucagon concentrations, in addition to diminished pancreas weights. These findings led us to subject RNA derived from SLC2A3-RNAi (RNA interference) and NTS-RNAi (non-targeting sequence) fetal pancreases to qPCR followed by transcriptomic analysis. We identified a total of 771 differentially expressed genes (DEGs). Upregulated pathways were associated with fat digestion and absorption, particularly fatty acid transport, lipid metabolism, and cholesterol biosynthesis, suggesting a potential switch in energetic substrates due to hypoglycemia. Pathways related to molecular transport and cell signaling in addition to pathways influencing growth and metabolism of the developing pancreas were also impacted. A few genes directly related to gluconeogenesis were also differentially expressed. Our results suggest that fetal hypoglycemia during the first half of gestation impacts fetal pancreas development and function that is not limited to ß cell activity.

Congenital Hyperinsulinism Caused by Mutations in ABCC8 Gene Associated with Early-Onset Neonatal Hypoglycemia: Genetic Heterogeneity Correlated with Phenotypic Variability.

Congenital hyperinsulinism (CHI) is a rare disorder of glucose metabolism and is the most common cause of severe and persistent hypoglycemia (hyperinsulinemic hypoglycemia, HH) in the neonatal period and childhood. Most cases are caused by mutations in the ABCC8 and KCNJ11 genes that encode the ATP-sensitive potassium channel (KATP). We present the correlation between genetic heterogeneity and the variable phenotype in patients with early-onset HH caused by ABCC8 gene mutations. In the first patient, who presented persistent severe hypoglycemia since the first day of life, molecular genetic testing revealed the presence of a homozygous mutation in the ABCC8 gene [deletion in the ABCC8 gene c.(2390+1_2391-1)_(3329+1_3330-1)del] that correlated with a diffuse form of hyperinsulinism (the parents being healthy heterozygous carriers). In the second patient, the onset was on the third day of life with severe hypoglycemia, and genetic testing identified a heterozygous mutation in the ABCC8 gene c.1792C>T (p.Arg598*) inherited on the paternal line, which led to the diagnosis of the focal form of hyperinsulinism. To locate the focal lesions, (18)F-DOPA (3,4-dihydroxy-6-[18F]fluoro-L-phenylalanine) positron emission tomography/computed tomography (PET/CT) was recommended (an investigation that cannot be carried out in the country), but the parents refused to carry out the investigation abroad. In this case, early surgical treatment could have been curative. In addition, the second child also presented secondary adrenal insufficiency requiring replacement therapy. At the same time, she developed early recurrent seizures that required antiepileptic treatment. We emphasize the importance of molecular genetic testing for diagnosis, management and genetic counseling in patients with HH.

Pathogenic Potential of a PCK1 Gene Variant in Cytosolic PEPCK Deficiency: A Compelling Case Study.

BACKGROUND Cytosolic phosphoenolpyruvate carboxykinase (PEPCK-C) deficiency is an extremely rare autosomal recessive inherited error of metabolism in which gluconeogenesis is impaired, resulting in life-threatening episodes of hypoglycemia and metabolic acidosis. The diagnosis of gluconeogenesis disorders is challenging. In the diagnostic pathway, the molecular test plays a paramount role. CASE REPORT The aim of the paper is to present the case report of a girl with recurrent episodes of severe hypoglycemia, in whom molecular diagnosis enabled the confirmation of PEPCK - C deficiency. The patient experienced 4 episodes of severe hypoglycemia. Most of them were accompanied by hyperlacticaemia, metabolic acidosis, and elevated liver enzymes. All of the metabolic decompensations were triggered by infectious agents. The episodes resolved after continuous infusion of high-dose glucose. Due to the recurrent character of the disease, a genetic condition was suspected. The differential diagnosis included metabolic and endocrinological causes of hypoglycemia. Two variants in the PCK1 gene were detected: c.265G>A p.(Glu89Lys) in exon 3 and c.925G>A p.(Gly309Arg) in exon 6. As c.925G>A p.(Gly309Arg) is a known pathogenic variant, the second variant was first described in June 2023 in the ClinVar database and described as "with unknown clinical significance". CONCLUSIONS According to the clinical symptoms observed in the presented case, the variant c.265G>A p.(Glu89Lys) in PCK1 gene should be considered likely pathogenic. We suggest considering molecular diagnostics in every patient presented with recurrent, severe hypoglycemia with accompanying liver damage as most accurate, feasible, and reliable method.

[Clinical and genetic analysis of two children with 3-hydroxy-3-methylglutaryl-CoA lyase deficiency].

OBJECTIVE: To explore the clinical characteristics and genetic variants of two children with 3-hydroxy-3-methylglutaryl-coenzyme A lyase deficiency (HMGCLD). METHODS: Two children with HMGCLD diagnosed at Henan Provincial Children's Hospital respectively in December 2019 and June 2022 were selected as the study subjects. Clinical data and results of laboratory testing were analyzed retrospectively. RESULTS: Both children had manifested with repeated convulsions, severe hypoglycemia, metabolic acidosis and liver dysfunction. Blood amino acids and acylcarnitine analysis showed increased 3-hydroxy-isovalyl carnitine (C5OH) and 3-hydroxy-isovalyl carnitine/capryloyl carnitine ratio (C5OH/C8), and urinary organic acid analysis showed increased 3-hydroxyl-3-methyl glutaric acid, 3-methyl glutaric acid, 3-methyl glutaconic acid, 3-hydroxyisoglycine and 3-methylprotarylglycine. Child 1 was found to harbor homozygous c.722C>T variants of the HMGCL gene, which was rated as uncertain significance (PM2_Supporting+PP3). Child 2 was found to harbor homozygous c.121C>T variants of the HMGCL gene, which was rated as pathogenic variant (PVS1+PM2_Supporting+PP4). CONCLUSION: Acute episode of HMGCLD is usually characterized by metabolic disorders such as hypoglycemia and metabolic acidosis, and elevated organic acids in urine may facilitate the differential diagnosis, though definite diagnosis will rely on genetic testing.

Metabolomic associations of impaired awareness of hypoglycaemia in type 1 diabetes.

This study investigates impaired awareness of hypoglycaemia (IAH), a complication of insulin therapy affecting 20-40% of individuals with type 1 diabetes. The exact pathophysiology is unclear, therefore we sought to identify metabolic signatures in IAH to elucidate potential pathophysiological pathways. Plasma samples from 578 individuals of the Dutch type 1 diabetes biomarker cohort, 67 with IAH and 108 without IAH (NAH) were analysed using the targeted metabolomics Biocrates AbsoluteIDQ p180 assay. Eleven metabolites were significantly associated with IAH. Genome-wide association studies of these 11 metabolites identified significant single nucleotide polymorphisms (SNPs) in C22:1-OH and phosphatidylcholine diacyl C36:6. After adjusting for the SNPs, 11 sphingomyelins and phosphatidylcholines were significantly higher in the IAH group in comparison to NAH. These metabolites are important components of the cell membrane and have been implicated to play a role in cell signalling in diabetes. These findings demonstrate the potential role of phosphatidylcholine and sphingomyelins in IAH.

Genotype-histotype-phenotype correlations in hyperinsulinemic hypoglycemia.

Hyperinsulinemic hypoglycemia (HH) of pancreatic origin includes congenital hyperinsulinism (CHI), insulinoma, insulinomatosis, and adult-onset non-insulinoma persistent hyperinsulinemic hypoglycemia syndrome (NI-PHHS). In this review, we describe the genotype-histotype-phenotype correlations in HH and their therapeutic implications. CHI can occur from birth or later on in life. Histologically, diffuse CHI shows diffuse beta cell hypertrophy with a few giant nuclei per islet of Langerhans, most frequently caused by loss-of-function mutations in ABCC8 or KCNJ11. Focal CHI is histologically characterized by focal adenomatous hyperplasia consisting of confluent hyperplastic islets, caused by a paternal ABCC8/KCNJ11 mutation combined with paternal uniparental disomy of 11p15. CHI in Beckwith-Wiedemann syndrome is caused by mosaic changes in the imprinting region 11p15.4-11p15.5, leading to segmental or diffuse overgrowth of endocrine tissue in the pancreas. Morphological mosaicism of pancreatic islets is characterized by occurence of hyperplastic (type 1) islets in one or a few lobules and small (type 2) islets in the entire pancreas. Other rare genetic causes of CHI show less characteristic or unspecific histology. HH with a predominant adult onset includes insulinomas, which are pancreatic insulin-producing endocrine neoplasms, in some cases with metastatic potential. Insulinomas occur sporadically or as part of multiple endocrine neoplasia type 1 due to MEN1 mutations. MAFA mutations may histologically lead to insulinomatosis with insulin-producing neuroendocrine microadenomas or neuroendocrine neoplasms. NI-PHHS is mainly seen in adults and shows slight histological changes in some patients, which have been defined as major and minor criteria. The genetic cause is unknown in most cases. The diagnosis of HH, as defined by genetic, histological, and phenotypic features, has important implications for patient management and outcome.

An extremely rare case of hypoglycemia with a novel mutation and review of the literature: fructose-1,6 bisphosphatase deficiency in an adult man.

Hypoglycemia is an uncommon clinical problem among non-diabetic patients. It requires systematic evaluation to determine the etiology. It may be related to critical illness, hepatic insufficiency, renal insufficiency, cardiac insufficiency, drugs, alcohol, cortisol insufficiency, growth hormone insufficiency, insulinoma, gastric bypass surgery, and paraneoplastic (insulin-like growth factor-2-related) immune-mediated or inherited metabolic disorders. We aimed to summarize the literature and present a case who suffered from hypoglycemia throughout his life and was diagnosed with fructose-1, 6 bisphosphatase deficiency in adulthood to attract attention to the rare causes of hypoglycemia in adulthood.

Novel compound heterozygous mutations of the FBP1 gene in a patient with hypoglycemia and lactic acidosis: A case report.

BACKGROUND: Fructose-1,6-bisphosphatase (FBPase) deficiency, caused by an FBP1 mutation, is an autosomal recessively inherited metabolic disorder characterized by impaired gluconeogenesis. Due to the rarity of FBPase deficiency, the mechanism by which the mutations cause enzyme activity loss still remains unclear. METHODS: We report a pediatric patient with typical FBPase deficiency who presented with hypoglycemia, hyperlactatemia, metabolic acidosis, and hyperuricemia. Whole-exome sequencing was used to search for pathogenic genes, Sanger sequencing was used for verification, and molecular dynamic simulation was used to evaluate how the novel mutation affects FBPase activity and structural stability. RESULTS: Direct and allele-specific sequence analysis of the FBP1 gene (NM_000507) revealed that the proband had a compound heterozygote for the c. 490 (exon 4) G>A (p. G164S) and c. 861 (exon 7) C>A (p. Y287X, 52), which he inherited from his carrier parents. His father and mother had heterozygous G164S and Y287X mutations, respectively, without any symptoms of hypoglycemia. CONCLUSION: Our results broaden the known mutational spectrum and possible clinical phenotype of FBP1.

Analysis of 6 cases with hepatocerebral mitochondrial DNA depletion syndrome and literature review / 中华儿科杂志

Objective: To explore the clinical features of hepatocerebral mitochondrial DNA depletion syndrome (MDS). Methods: The clinical data of 6 hepatocerebral MDS patients diagnosed in the Jinshan Hospital of Fudan University from January 2012 to December 2019 were retrospectively collected and analyzed. Related literature published before January 2020 were searched with the key words of "DGUOK""MPV17""POLG""C10orf2" in PubMed, China national knowledge infrastructure (CNKI) and Wanfang database. Results: All the 6 hepatocerebral MDS cases were male. The age of onset ranged from 3 days to 8 months. The most common initial symptoms were cholestasis and developmental retrogression. The main clinical manifestations included hepatomegaly (4 cases), hypotonia (3 cases), growth retardation (4 cases), cholestasis (5 cases), coagulopathy (5 cases), hypoalbuminemia (3 cases), hypoglycemia (4 cases), hyperlactacidemia (5 cases), and abnormal blood metabolism screening (6 cases). The isotope hepatobiliary imaging revealed no gallbladder and intestinal tract development within 24 hours in 2 patients. Regarding the cranial imaging examination, the head CT found widening of the extracranial space in 1 case, the brain magnetic resonance imaging (MRI) found ventricular enlargement in 2 cases, and the brain ultrasound found peripheral white matter injury in 1 case. Two cases were lost to follow-up, one died of liver failure, and three died of multiple organ failure due to aggravated infection. Among the 6 cases, there were 3 with MPV17 variation (c.182T>C and c.279G>C were novel), 1 with POLG variation (c.2993G>A was novel), 1 with DGUOK variation (c.679G>A homozygous mutation, parthenogenetic diploid of chromosome 2) and 1 with C10orf2 variation (c.1186C>T and c.1504C>T were novel). The literature review found that 129, 100, 51 and 12 cases of hepatocerebral MDS were caused by DGUOK, MPV17, POLG and C10orf2 gene variations, respectively. And the most common clinical manifestations were liver dysfunction presented with cholestasis and elevated transaminase, metabolic disorders including hypoglycemia and hyperlactacidemia, and diverse neurologic symptoms including developmental retardation, hypotonia, epilepsy and peripheral neuropathy. Besides, 1/3 of the patients with C10orf2 variation developed renal tubular injury. Conclusions: Hepatocerebral MDS mainly present with liver dysfunction, metabolic disorder and neuromuscular impairment. Different genotypes show specific clinical manifestations.

Analysis of a child with carnitine palmitoyl transferase 1A deficiency due to variant of CPT1A gene / 中华医学遗传学杂志

OBJECTIVE@#To report on the clinical, metabolic and genetic characteristics of a child with carnitine palmitoyl transferase 1A (CPT1A) deficiency.@*METHODS@#Clinical data and the level of acylcarnitine for a child who initially presented as epilepsy were analyzed. Genomic DNA was extracted from peripheral blood samples of the child and her parents and subjected to next-generation sequencing (NGS).@*RESULTS@#Mass spectrometry of blood acylcarnitine indicated increased carnitine 0 (C0) and significantly increased C0/ (C16+C18). DNA sequencing revealed that the child has carried compound heterozygous variants of the CPT1A gene, namely c.1846G>A and c.2201T>C, which were respectively inherited from her mother and father.@*CONCLUSION@#CPT1A presenting initially as epilepsy was unreported previously. Analysis of blood acylcarnitine C0 and C0/ (C16 + C18) ratio and NGS are necessary for the identification and diagnosis of CPT1A deficiency. The c.1846G>A and c.2201T>C variants of the CPT1A gene probably underlay the disease in this child. Above finding has also enriched the spectrum of CPT1A gene variants.

Heterogeneidad clínica y genética del hiperinsulinismo congénito / Clinical and genetic heterogeneity of congenital hyperinsulinism

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Energy intake underreporting of adults in a household survey: the impact of using a population specific basal metabolic rate equation / Subestimativa da ingestão energética em amostra probabilística de adultos: o impacto do uso de equações específicas para taxa metabólica basal / Subestimación de la ingesta energética en una muestra probabilística de adultos: el impacto del uso de ecuaciones específicas para la tasa metabólica basal

The purpose of the present study was to identify energy intake (EI) underreporting and to estimate the impact of using a population specific equation for the basal metabolic rate (BMR) in a probability sample of adults from Niterói, Rio de Janeiro State, Brazil. A sample of 1,726 subjects participated in the study. EI was assessed by a 24-hour dietary recall and EI/BMR was computed with BMR estimated using internationally recommended equations as well as specific equations developed for the adult population of Niterói. Mean EI was 1,570.9 and 2,188.8kcal.day-1 for women and men, respectively. EI decreased with increasing age in both men and women. BMR estimated by the Brazilian equation was significantly lower than the values estimated by the international equation for all age, sex and nutritional status groups. In general, EI underreporting was found in at least 50% of the population, higher in women, and increased with increasing age and body mass index (BMI). The results of the present study confirm that EI is underreported, even when BMR is estimated using population-specific equations.

O objetivo do presente estudo foi identificar a subestimativa da ingestão energética (IE) e estimar o impacto do uso de uma equação específica da população para a taxa metabólica basal (TMB), em amostra probabilística de adultos do Município de Niterói, Rio de Janeiro, Brasil. Uma amostra de 1.726 indivíduos da população adulta participou do estudo. Ingestão energética foi avaliada por um recordatório de 24 horas e IE/TMB foi calculada com TMB estimada pelas equações recomendadas e pelas equações específicas para a população. A média da IE foi 1.570,9 e 2.188,8kcal.dia-1 em mulheres e homens, respectivamente. A ingestão energética diminuiu com o aumento da idade em homens e mulheres. A taxa metabólica basal estimada pela equação brasileira foi significativamente menor do que os valores estimados pela equação recomendada para todas as idades, sexo e estado nutricional. Em geral, a subestimativa da IE foi encontrada em pelo menos 50% da população, maior em mulheres, e aumentou com o avanço da idade e índice de massa corporal (IMC). Os resultados confirmam que IE é subestimada, mesmo quando a TMB é estimada pelas equações da população específica.

El objetivo del presente estudio fue identificar la subestimación de la ingesta energética (IE) y estimar el impacto del uso de una ecuación específica de la población para la tasa metabólica basal (TMB), en una muestra probabilística de adultos del municipio de Niterói, Río de Janeiro, Brasil. Una muestra de 1.726 individuos de la población adulta participó en el estudio. La ingesta energética fue evaluada mediante un recordatorio de 24 horas y las IE/TMB fueron calculadas con una TMB estimada por las ecuaciones recomendadas y por las ecuaciones específicas para la población. La media de la IE fue 1.570,9 y 2.188,8kcal.día-1 en mujeres y hombres, respectivamente. La ingesta energética disminuyó con el aumento de la edad en hombres y mujeres. La tasa metabólica basal estimada por la ecuación brasileña fue significativamente menor que los valores estimados por la ecuación recomendada para todas las edades, sexo y estado nutricional. En general, la subestimación de la IE se encontró en por lo menos un 50% de la población, fue mayor en mujeres y aumentó con el aumento de la edad e índice de masa corporal (IMC). Los resultados confirman que la IE está subestimada, incluso cuando la TMB está estimada por las ecuaciones de población específica.

Hyperinsulinism/hyperammonemia (HI/HA) syndrome due to a mutation in the glutamate dehydrogenase gene / Síndrome de hiperinsulinemia/hiperamonemia devido a uma mutação no gene da glutamato desidrogenase

The hyperinsulinism/hyperammonemia (HI/HA) syndrome is a rare autosomal dominant disease manifested by hypoglycemic symptoms triggered by fasting or high-protein meals, and by elevated serum ammonia. HI/HA is the second most common cause of hyperinsulinemic hypoglycemia of infancy, and it is caused by activating mutations in GLUD1, the gene that encodes mitochondrial enzyme glutamate dehydrogenase (GDH). Biochemical evaluation, as well as direct sequencing of exons and exon-intron boundary regions of the GLUD1 gene, were performed in a 6-year old female patient presenting fasting hypoglycemia and hyperammonemia. The patient was found to be heterozygous for one de novo missense mutation (c.1491A>G; p.Il497Met) previously reported in a Japanese patient. Treatment with diazoxide 100 mg/day promoted complete resolution of the hypoglycemic episodes. Arq Bras Endocrinol Metab. 2012;56(8):485-9.

A síndrome de hiperinsulinemia/hiperamonemia (HI/HA) é uma condição rara, de herança autossômica dominante, que se manifesta por sintomas de hipoglicemia desencadeada por jejum ou refeições de alto conteúdo proteico, juntamente com elevação da concentração de amônia sérica. HI/HA é a segunda causa de hipoglicemia hiperinsulinêmica da infância e é causada por mutações ativadoras no GLUD1, o gene que codifica a enzima mitocondrial glutamato desidrogenase (GDH). A avaliação bioquímica, bem como o sequenciamento direto dos éxons e junções éxon-íntron do gene GLUD1, foi realizada em uma paciente de 6 anos de idade com hipoglicemia de jejum e hiperamonemia. A paciente apresentava uma mutação de novo missense (c.1491A>G; p.Il497Met) em heterozigose, que havia sido previamente relatada em um paciente japonês. O tratamento com diazóxido 100 mg/dia promoveu resolução completa dos episódios hipoglicêmicos. Arq Bras Endocrinol Metab. 2012;56(8):485-9.

Hiperinsulinismo monogénico / Monogenic hyperinsulinism

El término hiperinsulinismo monogénico se refiere a casos de hiperinsulinemia causados por mutaciones en un solo gen. Los pacientes presentan hipoglucemias de ayuno recurrentes, niveles inadecuados de insulina e incremento de la glucemia tras la administración de glucagón endovenoso. Además, no existe cetonemia, cetonuria ni acidosis. La principal causa de este cuadro clínico son las canelopatías, en las que el hiperinsulinismo está producido por alteraciones estructurales de los canales de potasio dependientes del ATP como consecuencia de mutaciones en el receptor de la sulfonilurea 1 (SUR1) o en el rectifi cador interno de los canales de potasio (Kir6.2). La segunda causa más común es el síndrome de hiperinsulinismo-hiperamonemia, originado por mutaciones activadoras de la enzima glutamato deshidrogenasa (GDH). Este síndrome se caracteriza por cuadros de hipoglucemia hiperinsulinémica con niveles elevados de amonio, que pueden ser provocados por la ingestión de una comida rica en proteínas. Otra causa de hiperinsulinismo monogénico es el hiperinsulinismo inducido por mutaciones activadoras en el gen de la glucocinasa (GGK). Finalmente, debe incluirse también la mutación en la enzima mitocondrial 3-hidroxiacil-CoA deshidrogenasa de cadena corta (SCHAD), que cataliza el tercero de los cuatro pasos de la oxidación de los ácidos grasos en la mitocondria

The term monogenic hyperinsulinism refers to cases of hyperinsulinism caused by mutations in a single gene. The affected patients show recurrent fasting hypoglycemia, inadequate serum insulin levels, and an increase in plasma glucose levels following the administration of intravenous glucagon. In addition, there is an absence of ketonemia, ketonuria and acidosis. The main causes of these syndromes are channelopathies, in which hyperinsulinism is caused by structural changes in the ATP-sensitive potassium channels due to mutations in sulfonylurea receptor 1 (SUR1) or in Kir6.2, the pre-forming subunit of this channel. The second most frequent cause is the hyperinsulinism/hyperammonemia syndrome, caused by activating mutations of the glutamate dehydrogenase (GDH) enzyme. This syndrome is characterized by episodes of hypoglycemia with hyperinsulinism and elevated levels of ammonium, which can be triggered by the ingestion of a protein- rich meal. Monogenic hyperinsulinism can also be induced by activating mutations of the glucokinase gene. Finally, mutations of mitochondrial short-chain 3-hydroxyacyl-coenzyme A dehydrogenase (SCHAD), which catalyses the third of the four steps in mitochondrial fatty acid oxidation, should also be included

Déficit de acetoacetil-CoA tiolasa mitocondrial: inicio en el período neonatal / Mitochondrial acetoacetyl-CoA Thiolase deficiency: neonatal onset

Presentamos el caso de un recién nacido de cuatro días de vida con deshidratación grave, polipnea, hipertonía y letargia. Los exámenes complementarios revelaron una acidosis metabólica grave con cetonemia, cetonuria y aumento del anión GAP. El análisis de orina reveló una excreción aumentada de ácido 2-metil-3-hidroxibutirato, tiglicina y 2-metilacetoacetato. El inicio neonatal del déficit de acetoacetil-CoA tiolasa (T2) es muy infrecuente. En la mayoría de los casos, los pacientes no presentan clínica en el período neonatal. Debemos pensar en esta entidad cuando un paciente presente una acidosis metabólica aguda, cetosis con glucemia normal y aciduria. La orina presenta aumento de las concentraciones de 2-metilacetoacetato y sus productos de descarboxilación. Este error innato del metabolismo en período neonatal puede producir graves alteraciones hidroelectrolíticas en forma de un proceso gradual o agudo que ocasionalmente puede causar la muerte del paciente

We present the case of a 4-day-old newborn with serious dehydration, polypnea, hypertonus and lethargy. Blood analysis showed severe metabolic acidosis with ketonemia, ketonuria and elevation of the GAP anion. Urine analysis revealed increased excretion of 2-methyl-3-hydroxybutyrate acid, tiglycine, and 2-methylacetoacetate acid. Neonatal onset of mitochondrial acetoacetyl-CoA thiolase (T2) deficiency is exceptional. Most patients have no clinical symptoms in the neonatal period. This entity should be considered in patients with acute metabolic acidosis and ketosis with normal glycemia and aciduria. The urine contains large amounts of 2-methylacetoacetate and its decarboxylation products. In the neonatal period, this inherited disorder of metabolism can produce severe hydroelectrolyte disorders in the form of a gradual process or acute episodes, which can occasionally be fatal

Hipoglucemia por hiperinsulinismo. A propósito de un caso / Hypoglycemia by hyperinsulinism. To purpose of a case

Se presenta un recién nacido con hipoglucemia refractaria al tratamiento, secundario e hiperinsulinismo. Se describen los hallazgos clínicos, de laboratorio, los diagnósticos diferenciales y el tratamiento con el propósito de analizar esta patología infrecuente. (AU)

Hipoglicemia secundaria a hipopituitarismo congénito / Hypoglycemia secundary a congenital hipopituitarism

La hipoglicemia es la manifestación inicial de los pacientes con hipopituitarismo congénito, especialmente en el período neonatal, en la mayoría de los casos se asocia a defectos en la línea media, sin déficid pondoestatural al momento del nacimiento, ni en los primeros meses de vida. Se presenta el caso de lactante mayor con hipoglicemia y convulsiones generalizadas, sin alteraciones al examen físico. El perfil endocrinológico reportó insuficiencia hipofisiaria