Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0025362 (mental retardation)
15,878 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Glutaric aciduria is a disorcer of lysine, tryptophan, and hydroxylysine metabolism characterized by intermittent metabolic acidemia, dystonia, athetosis and mental retardation. It is due to a recessively inherited deficiency of glutaryl-CoA dehydrogeanse, the enzyme(s) which catalyze the dehydrogenation of glutaryl-CoA to glutaconyl-CoA and decarboxylation of the latter to crotonyl-CoA. Abnormal quantities of glutaric, beta-hydroxyglutaric, and glutaconic acids are found in the urine of these patients. The nature of the movement disorder prompted study of the effects of the abnormally excreted metabolites on brain glutamate decarboxylase, an enzyme implicated in the pathogenesis of Huntington's chorea. Glutamate decarboxylase activity was examined in rat and rabbit brain acetone powders, stabilized with pyridoxal phosphate and glutathione. Glutarate, beta-hydroxyglutarate, and glutaconate were competitive inhibitors of this emzyme, Ki values being 1.3 X 10(-3) mol/l, 2.5 X 10(-4) mol/l, respectively. This inhibition may explain the neurological accompaniments of this syndrome.
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PMID:Inhibition of brain glutamate decarboxylase by glutarate, glutaconate, and beta-hydroxyglutarate: explanation of the symptoms in glutaric aciduria? 124 44

D-2-Hydroxyglutaric aciduria has been observed in patients with extremely variable clinical symptoms, creating doubt about the existence of a disease entity related to the biochemical finding. An international survey of patients with D-2-hydroxyglutaric aciduria was initiated to solve this issue. The clinical history, neuroimaging, and biochemical findings of 17 patients were studied. Ten of the patients had a severe early-infantile-onset encephalopathy characterized by epilepsy, hypotonia, cerebral visual failure, and little development. Five of these patients had a cardiomyopathy. In neuroimaging, all patients had a mild ventriculomegaly, often enlarged frontal subarachnoid spaces and subdural effusions, and always signs of delayed cerebral maturation. In all patients who underwent neuroimaging before 6 months, subependymal cysts over the head or corpus of the caudate nucleus were noted. Seven patients had a much milder and variable clinical picture, most often characterized by mental retardation, hypotonia, and macrocephaly, but sometimes no related clinical problems. Neuroimaging findings in 3 patients variably showed delayed cerebral maturation, ventriculomegaly, or subependymal cysts. Biochemical findings included elevations of D-2-hydroxyglutaric acid in urine, plasma, and cerebrospinal fluid in both groups. Cerebrospinal fluid gamma-aminobutyric acid was elevated in almost all patients investigated. Urinary citric acid cycle intermediates were variably elevated. The conclusion of the study is that D-2-hydroxyglutaric aciduria is a distinct neurometabolic disorder with at least two phenotypes.
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PMID:D-2-Hydroxyglutaric aciduria: biochemical marker or clinical disease entity? 989 84

L-2-Hydroxyglutaric aciduria (L-2-HGA) is a rare organic aciduria with a slowly progressive course regarding CNS involvement. We present a 13.5-year-old female patient who presented at the Emergency Department with a generalized status epilepticus, which promptly responded to intravenous phenytoin. CT and MRI demonstrated subcortical white matter alterations. The neurological examination revealed mild mental retardation, macrocephaly and ataxic gait with cerebellar signs. Repeated urinary organic acid analysis demonstrated increased excretion of 2-hydroxyglutaric acid which was of the L-configuration. The constellation of macrocephaly in a patient with mental retardation, cerebellar tract involvement and subcortical white matter signal alterations on MRI should alert the physician to the possibility of L-2-HGA. Although rare, epileptic seizures or even status epilepticus can be among the presenting symptoms in organic acidurias with a slow course, such as L-2-HGA.
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PMID:L-2-Hydroxyglutaric aciduria presenting as status epilepticus. 1137 7

L-2-hydroxyglutaric aciduria (L2HGA) is a chronic slowly progressive neurodegenerative disease characterized mainly by psychomotor developmental delay and cerebellar dysfunction. We report the clinical, biochemical, and neuroimaging features of 29 patients from 22 families. The mean age at the time of diagnosis was 13.4 years (2.5-32 years). The mean follow-up period of patients was four years (1.5-16 years). The main clinical findings were mental retardation and cerebellar involvement with ataxic gait and intentional tremor. Additional findings were mental retardation, macrocephaly and seizures. Diagnosis was confirmed by increased urinary excretion of L-2-hydroxyglutaric acid in all patients and highly specific magnetic resonance imaging (MRI) pattern showing subcortical leukoencephalopathy with bilateral high signal intensity in dentate nuclei and putamens. During the follow-up period, all patients had a static encephalopathy course. The underlying metabolic defect and the possible role of L-2-hydroxyglutaric acid are studied in a subgroup of these families and under evaluation for publication.
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PMID:L-2-hydroxyglutaric aciduria: a report of 29 patients. 1588 21

L-2-Hydroxyglutaric aciduria (L-2-HGA) is a rare progressive neurometabolic disease, defined as a characteristic clinical and radiological entity, mainly including mental retardation, cerebellar dysfunction and involvement of the subcortical white matter, cerebellum and basal ganglia on brain MRI. The biochemical hallmark is an increased urinary excretion of L-2-hydroxyglutaric acid. Management is only supportive. A child born to a Turkish mother in whom L-2-HGA was previously diagnosed is reported. Although pregnancy was repeatedly advised against because of the important degree of mental retardation and the potential risk of a toxic effect on the embryo and/or fetus (at that time no reports of maternal L-2-HGA were available), she became pregnant at 30 years of age and the pregnancy passed uneventfully. On amniocentesis, performed at 5 months of gestational age, elevated 2-hydroxyglutarate, previously shown to be almost exclusively the L-2-stereoisomer, was present in the amniotic fluid: 27.5mu mol/L (controls <1.3; n=5). The child, not affected by the disease as shown by a normal urinary excretion of 2-hydroxyglutaric acid, was normal at birth. When last examined at the age of 3 years, both somatic and mental development were excellent. As the pathogenesis of the extensive brain damage in affected persons remains largely unknown, notwithstanding the recent identification of the mutated gene and the deficient enzyme, one can only speculate on the mechanism by which embryo and fetus from a L-2-HGA mother are spared, at least in this case.
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PMID:Normal pregnancy outcome in L-2-hydroxyglutaric aciduria. 1680 9

Introduction. Organic acidurias are a group of hereditary metabolic disorders characterized by an increase in excretion of organic acids in urine. L-2 hydroxyglutaric aciduria is a neurodegenerative disorder with insidious onset after infancy, which is likely inherited in an autosomal recessive mode, characterized by mental retardation, progressive ataxia, epilepsy, macrocephaly, pyramidalism and extrapyramidal symptoms in variable combinations, with subcortical encephalopathy and cerebral atrophy in neuroimaging studies. Biochemical diagnosis was based on the detection of high levels of L-2 hydroxyglutaric acid in body fluids. Clinical case. We present the case of a 42 year old male patient with psychomotor development delay, generalized tonic epileptic crisis, and ataxia and pyramidal syndrome after the age of 18 months. Neuroimaging study findings revealed subcortical leukoencephalopathy. Diagnosis of the disease was reached after measuring the level of L-2 hydroxyglutaric acid in body fluid (blood, urine and cerebrospinal fluid). This diagnosis was also confirmed in three of the patient's brothers who were affected by a non-filial neurological disease by measurement of this acid level in urine. The genetic study was performed in all the cases. Discussion. As with the majority of patients who reach adulthood without having been diagnosed of this disease during infancy, we believe that this disorder should be considered as a possibility in adults presenting a combination of the symptoms described and subcortical encephalopathy in magnetic resonance imaging, regardless of whether there is a family background of it. Thus, it should be included in the differential diagnosis of leukodystrophy in adult patients.
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PMID:[L-2 hydroxyglutaric aciduria: presentation of a family diagnosed in adulthood]. 1964 38

L-2-Hydroxyglutaric aciduria is a rare autosomal recessively inherited metabolic disorder of organic acid metabolism. Clinical findings are characterised by progressive neurological syndrome with cerebellar signs, mental deterioration and macrocephaly. Diagnosis is via increased levels of L-2 hydroxyglutaric acid in urine, plasma and cerebrospinal fluid. Brain magnetic resonance imaging (MRI) shows peripheral white matter abnormalities in cerebral hemispheres, basal ganglia and dentate nuclei. In this report, we present an rare 8-year-old patient with a rare mental retardation, cerebellar findings, macrocephaly and typical brain MRI findings, who was subsequently diagnosed with L-2-hydroxyglutaric aciduria. In conclusion, in patients with progressive mental retardation, macrocephaly and cerebral findings, L-2-hydroxyglutaric aciduria should be considered in case of deep white matter and dentate nuclei involvement in MRI.
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PMID:Contribution of brain MRI in a patient diagnosed with 2-hydroxyglutaric aciduria. 2378 58

L-2-hydroxyglutaric aciduria (L2HGA) is a neurometabolic disorder characterized by macrocephaly, seizures, progressive mental retardation, pyramidal signs, ataxia and tremor. Dystonia is an under-recognized feature of this entity in the literature. We report two siblings with L2HGA, one of whom presented with writer's cramp followed by dystonia of the other hand. An elevated plasma lysine, highly elevated urine 2-hydroxyglutaric acid, and MRI with characteristic findings (leukoencephalopathy of bilateral subcortical white matter sparing central white matter) suggested the diagnosis, which was confirmed by genetic testing.
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PMID:Writer's cramp as a presentation of L-2-hydroxyglutaric aciduria. 2678 35