RESUMEN
An Argentine male child died at 4.5 years of age of a lethal mitochondrial disease associated with a MELAS mutation and a Barth syndrome-like presentation. The child had severe failure to thrive from the early months and for approximately two years thereafter. In addition, the patient had severely delayed gross motor milestones, marked muscle weakness, and dilated cardiomyopathy that progressed to congestive heart failure. He also had persistently elevated urinary levels of 3-methylglutaconic and 2-ethylhydracrylic acids and low blood levels of cholesterol. Detailed histopathologic evaluation of the skeletal muscle biopsy showed high activity of succinate dehydrogenase, a generalized decrease of COX activity, and abundant ragged-red fibers. Electron microscopic studies revealed multiple mitochondrial abnormalities in lymphocytes and monocytes, in the striated muscle, and in the postmortem samples (muscle, heart, liver, and brain). Biochemical analysis showed a pronounced and constant lactic acidosis, and abnormal urinary organic acid excretion (unchanged in the fasting and postprandial states). In addition, in CSF there was a marked increase of lactate and beta-hydroxybutyrate (beta-HOB) and also a high systemic ratio beta-HOB/acetoacetate. Enzymatic assay of the respiratory chain in biopsied muscle showed 10% of complex I activity and 24% of complex IV activity compared with controls. Molecular studies of the mitochondrial genome revealed an A to G mutation at nucleotide pair 3243 in mitochondrial DNA, a well-known pathogenetic mutation (MELAS mutation) in all the patient's tissues and also in the blood specimens of the probands mother and sibs (4 of 5). The diagnosis of MELAS mutation was reinforced by the absence of an identifiable mutation in the X-linked G4.5 gene of the propositus. The present observation gives additional evidence of the variable clinical expression of mtDNA mutations in humans and demonstrates that all clinical variants deserve adequate investigation to establish a primary defect. It also suggests adding Barth-like syndrome to the list of phenotypes with the MELAS mutation.
Asunto(s)
ADN Mitocondrial/genética , Síndrome MELAS/genética , Mutación Puntual , Ácido 3-Hidroxibutírico/sangre , Ácidos/líquido cefalorraquídeo , Ácidos/orina , Argentina , Biopsia , Preescolar , Transporte de Electrón , Humanos , Lactatos/sangre , Lactatos/líquido cefalorraquídeo , Síndrome MELAS/diagnóstico , Masculino , Mitocondrias/enzimología , Músculo Esquelético/patología , Músculo Esquelético/ultraestructura , Fenotipo , SíndromeRESUMEN
Experienced clinicians recognize that some children who appear to have static cerebral palsy (CP) actually have underlying genetic-metabolic disorders. We report a series of patients with motor disorders seen in children with extrapyramidal CP in whom brain magnetic resonance imaging abnormalities provided important diagnostic clues in distinguishing genetic-metabolic disorders from other causes. One cause of static extrapyramidal CP, hypoxic-ischemic encephalopathy at the end of a term gestation, produces a characteristic pattern of hyperintense signal and atrophy in the putamen and thalamus. Other signal abnormalities and atrophy in the putamen, globus pallidus, or caudate can point to genetic-metabolic diseases, including disorders of mitochondrial and organic acid metabolism. Progress in understanding and treating genetic diseases of the developing brain makes it essential to diagnose disorders that masquerade as static CP. Brain magnetic resonance imaging is a useful diagnostic tool in the initial evaluation of children who appear to have CP.
Asunto(s)
Enfermedades de los Ganglios Basales/diagnóstico , Encefalopatías/diagnóstico , Encéfalo/patología , Parálisis Cerebral/diagnóstico , Imagen por Resonancia Magnética , Acidosis Láctica/diagnóstico , Atrofia , Encefalopatías/genética , Encefalopatías/metabolismo , Isquemia Encefálica/diagnóstico , Núcleo Caudado/patología , Cerebelo/patología , Preescolar , Diagnóstico Diferencial , Femenino , Globo Pálido/patología , Humanos , Enfermedad de Huntington/diagnóstico , Hipoxia Encefálica/diagnóstico , Lactante , Masculino , Errores Innatos del Metabolismo/diagnóstico , Encefalomiopatías Mitocondriales/diagnóstico , Trastornos del Movimiento/diagnóstico , Neurodegeneración Asociada a Pantotenato Quinasa/diagnóstico , Putamen/patología , Enfermedad por Deficiencia del Complejo Piruvato Deshidrogenasa/diagnóstico , Tálamo/patologíaRESUMEN
From the description of two pairs of siblings belonging to unrelated families, one Argentine family with a history of consanguinity and Irish ancestry and the other family native of Paraguay, in whom mitochondrial 2-methylacetoacetyl-CoA thiolase deficiency, commonly known as beta-ketothiolase deficiency (beta-KTD, McKusick 203750; EC 2.3.1.9) was recognized. We tried to outline through this experience the clinical and biochemical consequences of this genetic defect in the 6th step of the isoleucine catabolism. The phenotyoic expression presented by the patients belonged to the classical form of beta-KTD. Seven to 15 months was the age at onset of the uniform clinical pattern this being essentially an association of one or several severe ketoacidotic episodes and hyperglycemia which was observed in two patients. The thin-layer chromatography of the tiglylglycine, and dinitrophenylhydrazone of the butanone were positive; aminoacidemia and aminoaciduria revealed normal levels. The organic acids having a unique profile obtained through gaschromatography and mass-spectrometry (GC/MS) showed excretion of large quantities of metabolites characteristic of the disease: 2-methyl-3-hydroxybutirate, 2-methylacetoacetic acid, tiglylglycine and 2-ethylhydracrilic acid which led us to establish the biochemical diagnosis of beta-KTD. The assay of the beta-ketothiolase in lymphocytes and polymorphonuclear leukocytes of the only surviving patient (VT) showed absence of activation by the K+ ion when the acetoacetyl-CoA was used as a substrate. This first Argentine report about beta-KTD leads us to mention three amplifying aspects with regards to previous literature: it adds other different ethnic ancestries of patients, points out a morphological analysis of autopsy material with unchanged structures in the brain, liver and kidneys and marks in the patient VT a dissociation between a symptom-free clinical pattern since age 7 and the persistent biochemical abnormality until the present age, 15 years. The knowledge of the existence of these diseases in our country together with the availability and access to GC/MS of high precision and speed, will allow early diagnosis and better therapeutic results.
Asunto(s)
Acetil-CoA C-Aciltransferasa/deficiencia , Mitocondrias/enzimología , Argentina , Femenino , Humanos , Isoleucina/metabolismo , Cuerpos Cetónicos/metabolismo , Masculino , Errores Innatos del Metabolismo/diagnósticoRESUMEN
This paper describes the first Argentine case of 3-hydroxy-3-methylglutaric aciduria, a genetic defect of ketogenesis and leucine catabolism step. At the age of 4 months, the patient presented a life-threatening episode of hypoglucemia, metabolic acidosis and hyperammonemia resembling Reye syndrome. The lack of urinary ketone bodies, normal levels of plasma aminoacids and normal urinary excretion of p-hydroxyphenolic acids, led us to look for a ketogenic defect. An abnormal profile of urinary organic acids detected by thin layer chromatography and later characterized and quantified by gas chromatography-mass spectrometry (Figs. 1, 2; Table 1), showed a marked increase in the acidic metabolites typical of the 3-hydroxy-3-methylglutaric aciduria: 3-hydroxy-3-methylglutaric, 3-methylglutaconic, 3-methylglutaric and 3-hydroxyisovaleric acids. The activity of 3-hydroxy-3-methylglutaryl coenzyme A lyase was absent in white cell pellets and between 2-5% of the control values in skin fibroblasts (Table 2). Treatment of the disorder, mainly restricted leucine or low-protein diet and addition of L-carnitine had no significant effect on the severe neurological injuries present since the first illness. MRI of the brain, at the age of 1 year and 8 months, showed images in T1 suggestive of marked cerebral atrophy and in T2 hyperintensive images predominating in the right frontal and posterior parietal areas and of the punctiform lesions in the basal ganglia, particularly in the heads of both caudate nuclei.(ABSTRACT TRUNCATED AT 250 WORDS)
Asunto(s)
Aminoácidos/análisis , Daño Encefálico Crónico/etiología , Oxo-Ácido-Liasas/deficiencia , Cromatografía en Capa Delgada , Humanos , Lactante , Imagen por Resonancia Magnética , MasculinoRESUMEN
Se trata de la primera descripción en Argentina de una 3-hidroxi-3-metilglutárica aciduria (HMG-Aciduria), defecto genético de la cetogénesis hepática y en el último paso catabólico de la leucina. A la edad de 4 meses, el paciente debutó con un grave cuadro clínico evocador de un Síndrome de Reye; la ausencia de cambios en los aminoácidos séricos y urinários, como asimismo el no incremento en la excreción de los ácidos p-hidroxifenólicos y la presencia de acidosis metabólica sin cetosis, orientaron hacia defecto cetogénico. Un perfil anormal de ácidos orgánicos urinarios, detectado por cromatografía en capa delgada y luego caracterizado y cuantificado por cromatografía de gas-espectrometría de masa, demostró un muy marcado incremento de los metabolitos típicos de la HMG-Aciduria: 3-hidroxi-3-metilglutárico, 3 metilglutacónico, 3-metilglutárico y el 3-hidroxisovalérico. La actividad de la 3-hidroxi-3-metilglutaril-CoA Liasa en leucocitos y fibroblastos cultivados de una biopsia de piel del paciente, señaló una ausencia total en los primero y entre un 2-5% de los valores controles en los segundos. La terapia aplicada en base a una dieta restrictiva en leucina o hipoproteica, hipograsa y la administración continua de L-carnitina no logró mayores efecto sobre el cuadro neurológico ya evidenciado a partir de la primera crisis. La resonancia magnética del cerebro, realizada al año y 8 meses de edad, mostró en T1 imágenes sugestivas de una marcada atrofia cerebral y en T2 imágenes hiperintensas predominantes en la región frontal derecha y parietales posteriores y de tipo puntiforme en los ganglios basales, en particular en la cabeza de ambos núcleos caudados. Estos hallazgos eran compatibles con gliosis y/o desmielinización de la sustancia blanca y necrosis neuronal de la sustancia gris, objetivaciones en probable correlato al profundo retardo sicomotor convulsiones, microcefalia e hipotonía generalizada del niño e interpretado más bien como de tipo secuelar que como otra variante fenotípica de la enfermedad. De allí el acento en señalar la importancia de la alta presunción clínica y de la precocidad del tratamiento inicial sindrómico en la emergencia metabólica (AU)
Asunto(s)
Humanos , Masculino , Lactante , Acilcoenzima A/deficiencia , Aminoácidos/análisis , Cerebro/patología , Imagen por Resonancia Magnética , Cromatografía en Capa DelgadaRESUMEN
This paper describes the first Argentine case of 3-hydroxy-3-methylglutaric aciduria, a genetic defect of ketogenesis and leucine catabolism step. At the age of 4 months, the patient presented a life-threatening episode of hypoglucemia, metabolic acidosis and hyperammonemia resembling Reye syndrome. The lack of urinary ketone bodies, normal levels of plasma aminoacids and normal urinary excretion of p-hydroxyphenolic acids, led us to look for a ketogenic defect. An abnormal profile of urinary organic acids detected by thin layer chromatography and later characterized and quantified by gas chromatography-mass spectrometry (Figs. 1, 2; Table 1), showed a marked increase in the acidic metabolites typical of the 3-hydroxy-3-methylglutaric aciduria: 3-hydroxy-3-methylglutaric, 3-methylglutaconic, 3-methylglutaric and 3-hydroxyisovaleric acids. The activity of 3-hydroxy-3-methylglutaryl coenzyme A lyase was absent in white cell pellets and between 2-5
of the control values in skin fibroblasts (Table 2). Treatment of the disorder, mainly restricted leucine or low-protein diet and addition of L-carnitine had no significant effect on the severe neurological injuries present since the first illness. MRI of the brain, at the age of 1 year and 8 months, showed images in T1 suggestive of marked cerebral atrophy and in T2 hyperintensive images predominating in the right frontal and posterior parietal areas and of the punctiform lesions in the basal ganglia, particularly in the heads of both caudate nuclei.(ABSTRACT TRUNCATED AT 250 WORDS)
RESUMEN
This paper describes the first Argentine case of 3-hydroxy-3-methylglutaric aciduria, a genetic defect of ketogenesis and leucine catabolism step. At the age of 4 months, the patient presented a life-threatening episode of hypoglucemia, metabolic acidosis and hyperammonemia resembling Reye syndrome. The lack of urinary ketone bodies, normal levels of plasma aminoacids and normal urinary excretion of p-hydroxyphenolic acids, led us to look for a ketogenic defect. An abnormal profile of urinary organic acids detected by thin layer chromatography and later characterized and quantified by gas chromatography-mass spectrometry (Figs. 1, 2; Table 1), showed a marked increase in the acidic metabolites typical of the 3-hydroxy-3-methylglutaric aciduria: 3-hydroxy-3-methylglutaric, 3-methylglutaconic, 3-methylglutaric and 3-hydroxyisovaleric acids. The activity of 3-hydroxy-3-methylglutaryl coenzyme A lyase was absent in white cell pellets and between 2-5
of the control values in skin fibroblasts (Table 2). Treatment of the disorder, mainly restricted leucine or low-protein diet and addition of L-carnitine had no significant effect on the severe neurological injuries present since the first illness. MRI of the brain, at the age of 1 year and 8 months, showed images in T1 suggestive of marked cerebral atrophy and in T2 hyperintensive images predominating in the right frontal and posterior parietal areas and of the punctiform lesions in the basal ganglia, particularly in the heads of both caudate nuclei.(ABSTRACT TRUNCATED AT 250 WORDS)
RESUMEN
Se trata de la primera descripción en Argentina de una 3-hidroxi-3-metilglutárica aciduria (HMG-Aciduria), defecto genético de la cetogénesis hepática y en el último paso catabólico de la leucina. A la edad de 4 meses, el paciente debutó con un grave cuadro clínico evocador de un Síndrome de Reye; la ausencia de cambios en los aminoácidos séricos y urinários, como asimismo el no incremento en la excreción de los ácidos p-hidroxifenólicos y la presencia de acidosis metabólica sin cetosis, orientaron hacia defecto cetogénico. Un perfil anormal de ácidos orgánicos urinarios, detectado por cromatografía en capa delgada y luego caracterizado y cuantificado por cromatografía de gas-espectrometría de masa, demostró un muy marcado incremento de los metabolitos típicos de la HMG-Aciduria: 3-hidroxi-3-metilglutárico, 3 metilglutacónico, 3-metilglutárico y el 3-hidroxisovalérico. La actividad de la 3-hidroxi-3-metilglutaril-CoA Liasa en leucocitos y fibroblastos cultivados de una biopsia de piel del paciente, señaló una ausencia total en los primero y entre un 2-5% de los valores controles en los segundos. La terapia aplicada en base a una dieta restrictiva en leucina o hipoproteica, hipograsa y la administración continua de L-carnitina no logró mayores efecto sobre el cuadro neurológico ya evidenciado a partir de la primera crisis. La resonancia magnética del cerebro, realizada al año y 8 meses de edad, mostró en T1 imágenes sugestivas de una marcada atrofia cerebral y en T2 imágenes hiperintensas predominantes en la región frontal derecha y parietales posteriores y de tipo puntiforme en los ganglios basales, en particular en la cabeza de ambos núcleos caudados. Estos hallazgos eran compatibles con gliosis y/o desmielinización de la sustancia blanca y necrosis neuronal de la sustancia gris, objetivaciones en probable correlato al profundo retardo sicomotor convulsiones, microcefalia e hipotonía generalizada del niño e interpretado más bien como de tipo secuelar que como otra variante fenotípica de la enfermedad. De allí el acento en señalar la importancia de la alta presunción clínica y de la precocidad del tratamiento inicial sindrómico en la emergencia metabólica
Asunto(s)
Humanos , Masculino , Lactante , Acilcoenzima A/deficiencia , Aminoácidos/análisis , Cerebro/patología , Cromatografía en Capa Delgada , Imagen por Resonancia MagnéticaRESUMEN
Seven boys with an apparently X-linked syndrome of dilated cardiomyopathy, growth retardation, neutropenia, and persistently elevated urinary levels of 3-methylglutaconate, 3-methylglutarate, and 2-ethylhydracrylate were studied. The natural history of the disorder was characterized by severe or lethal cardiac disease and recurrent infections during infancy and early childhood but relative improvement in later childhood. The initial presentation of the syndrome varied from congenital dilated cardiomyopathy to infantile congestive heart failure to isolated neutropenia without clinical evidence of heart disease. The excretion of 3-methylglutaconate and 3-methylglutarate appeared to be independent of the metabolism of leucine, the presumed precursor of these organic acids in humans. Although the cause of the organic aciduria remains obscure, the constellation of biochemical and clinical abnormalities forms a distinct syndrome that may be a relatively common cause of dilated cardiomyopathy or neutropenia in boys during infancy and childhood.
Asunto(s)
Cardiomiopatía Dilatada/genética , Glutaratos/orina , Trastornos del Crecimiento/genética , Neutropenia/genética , Cromosoma X , Adulto , Cardiomiopatía Dilatada/metabolismo , Cardiomiopatía Dilatada/patología , Niño , Preescolar , Cromatografía Líquida de Alta Presión , Fumaratos/orina , Trastornos del Crecimiento/metabolismo , Insuficiencia Cardíaca/genética , Humanos , Masculino , Meglutol/análogos & derivados , Meglutol/orina , Enfermedades Musculares/genética , Enfermedades Musculares/patología , Neutropenia/metabolismo , Neutropenia/patología , Linaje , SíndromeRESUMEN
We report four patients with methylmalonic acidemia who developed acute extrapyramidal disease after metabolic decompensation. The neurologic findings resulted from bilateral destruction of the globus pallidus with variable involvement of the internal capsules. This complication was unrelated to a specific gene defect responsible for methylmalonic acidemia or to cyanocobalamin administration. These lesions constitute a "metabolic stroke," probably because of the accumulation of toxic organic acid metabolites, because they cannot be accounted for by hypoxemia or vascular insufficiency.
Asunto(s)
Errores Innatos del Metabolismo de los Aminoácidos/complicaciones , Enfermedades de los Ganglios Basales/patología , Encefalopatías Metabólicas/patología , Trastornos Cerebrovasculares/patología , Globo Pálido/patología , Malonatos/sangre , Ácido Metilmalónico/sangre , Adolescente , Errores Innatos del Metabolismo de los Aminoácidos/patología , Atrofia , Corteza Cerebral/patología , Preescolar , Femenino , Humanos , Masculino , Tomografía Computarizada por Rayos XRESUMEN
A four-month-old child with non-ketotic hypoglycemia and rapidly progressive cirrhosis excreted in her urine large amounts of two unidentified organic acids in addition to a spectrum of saturated, unsaturated, and 3-hydroxy dicarboxylic acids in her urine. Gas chromatography/mass spectrometry of the trimethylsilyl derivative of one of the unknown compounds suggested the structure of 3-hydroxyoctanoic acid, which was confirmed by similar analysis of the authentic compound. The same organic acid was found in the child's plasma. The significance of 3-hydroxyoctanoic aciduria as a possible marker for a primary defect of 3-hydroxy fatty acid metabolism is discussed.
Asunto(s)
Hidroxiácidos/orina , Hipoglucemia/orina , Femenino , Humanos , LactanteRESUMEN
We have seen three unrelated patients with the DiGeorge anomalad who also had the same deletion of chromosome 22 (pter leads to qll). In each, the remaining long arm material (qll leads to qter) was translocated to a different autosome. Our patients and a review of the literature, including a recent report of a family having four infants with the DiGeorge anomalad and the same deletion of chromosome 22 (de la Chapelle et al: Hum Genet 57:253, 1981), make a strong argument for at least some cases of the DiGeorge anomalad arising from a deletion of the pericentromeric region of chromosome 22.