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Query: UMLS:C0025362 (mental retardation)
 15,878 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The case is described of a child, age 6 1/2 years, with retarded mental development, mild neurological signs and abnormal metabolism of sulphur-containing amino acids and methylmalonate, due to an inborn error in the formation of vitamin B12 coenzymes. The patient was treated for almost three years with hydroxycobalamin, folic acid, pyridoxine and choline. Though physical growth was normal, she continued to demonstrate a moderate degree of mental retardation. A brother of the patient died at the age of 5 years, probably of a similar, but undiagnosed, disorder. As far as we are aware there are only four other reported cases similar to the case described here. Two of these patients died and in other other two the defect was so mild that no treatment was necessary and who, in fact, showed appreciable improvement during the follow-up period, which to date amounts to 3 years and 3 months. For reasons detailed in the discussion, it is suggested that the diagnosis of homocystinuria is not complete until studies of folate and vitamin B12 metabolism are undertaken at the same time, so as to identify the metabolic defect(s) responsible for the condition.
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PMID:A unique case of derangement of vitamin B12 metabolism. 102 7

Screening urine for inherited and acquired organic acidurias in newborns has the potential of preventing severe disease, mental retardation, and death. A method for screening dried urine filter paper samples for acidic markers of at least 20 different metabolic conditions has been developed. These conditions include, among others, maple syrup urine disease; methylmalonic, propionic, isovaleric, glutaric, and hydroxymethylglutaric acidurias; methylcrotonylglycinuria; medium-chain acyl-CoA dehydrogenase deficiency; inherited vitamin responsive disorders B12, biotin, B2), and acquired deficiencies of these vitamins. The preparation of the urine extract is identical to the method we use to screen infants for neuroblastoma. Screening is based on a highly sensitive and specific determination of eight organic acid markers by an automated computerized gas chromatography mass spectrometry system using selected ion monitoring. The markers used for screening are methylmalonic acid, 2-hydroxyisocaproic acid, glutaric acid, propionylglycine, isovalerylglycine, 3-methylcrotonylglycine, hexanoylglycine, and 3-phenylpropionylglycine. The extraction efficiencies of these acids from dried filter paper were similar to extraction from water, ranging from about 40% to 80%, except for propionylglycine which showed a low extraction efficiency of 11-13%. The stability of these acids on filter paper exposed to room air and temperature over a period of 15 d was adequate for the use of this collection method for organic aciduria screening. Normal levels, adjusted to urinary creatinine, were established for these acids in 519 urine filter paper samples obtained from 3-wk-old newborns. This screening method was tested on samples obtained from 12 patients with known organic acidurias including stored urine filter paper collected at 3-wk of age from two infants later found to have organic acidurias.
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PMID:Screening newborns for multiple organic acidurias in dried filter paper urine samples: method development. 195 13

Four patients with severe cerebral palsy, mental retardation, and seizures who were treated with valproic acid showed a broad spectrum of hematologic toxicity, which included thrombocytopenia, macrocytic red cells with or without anemia, and the Pelger-Huet anomaly in the segmented neutrophils, along with elevated vitamin B12 levels, normal serum folic acid levels, and elevated fetal hemoglobin values (two cases). Bone marrow findings in all four patients were abnormal, suggestive of a myelodysplastic syndrome. These hematologic findings have not been previously reported and are important for monitoring a patient on valproic acid therapy. The Pelger-Huet anomaly may be mistaken for an elevated band count, the macrocytic anemia appears not to be secondary to a vitamin B12 or folate deficiency, and the thrombocytopenia may be sensitive to drug dosage. The bone marrow changes appear to be a drug-related myelodysplastic phenomenon.
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PMID:Severe hematologic toxicity of valproic acid. A report of four patients. 210 2

Sibling cases of familial vitamin E deficiency accompanied by ataxia, polyneuropathy and mental retardation were reported. Case 1 was a 37-year-old male who developed progressive gait disturbance, deformity of the feet and head tremor from childhood, after normal delivery and development of early childhood. On physical examination, he had cataract, high arched palate and pes cavus. Neurological examination revealed mental retardation (WAIS 68), scanning speech, muscular atrophy of the face and extremities with predominance in the lower limbs, absent Achilles tendon reflex, disturbance of superficial and deep sensation predominant in distal limbs, and marked gait ataxia. Ataxia was both cerebellar and sensory in nature. Laboratory data of the blood showed no significant abnormalities including blood glucose and vitamin B12 except a markedly low level of serum vitamin E. The brain CT scan revealed severe cerebellar atrophy and marked dilatation of the cisterna magna and the subarachnoid space around the cerebellum. Motor nerve conduction velocity in the leg was decreased. Biopsy specimen from the quadriceps muscle showed neurogenic atrophy. Sural nerve biopsy revealed decrease in large myelinated fibers with axonal degeneration and regeneration. Oral administration of alpha-tocopherol acetate, 600 mg per day, diminished ataxia significantly. Based on lysosomal enzyme activity in leukocytes, clinical and laboratory examination, lipidosis or spinocerebellar degeneration was excluded. Chronic lipid malabsorption or beta lipoprotein deficiency which can cause decrease in vitamin E absorption, was not recognized. On oral loading with 2 g of alpha-tocopherol acetate, the decrease rate of serum vitamin E was normal. Consequently the low vitamin E was considered to have resulted from selective impairment of vitamin E absorption.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:[Familial idiopathic vitamin E deficiency associated with cerebellar atrophy]. 226 7

A Turkish girl presented with a history of fever, diarrhoea, convulsions, recurrent infections and failure to thrive from the age of 5 months. Megaloblastic anaemia was present and profound folate deficiency was evidenced in plasma and in CSF. Treatment with oral folic acid cured the anaemia, diarrhoea and infections but failed to prevent convulsions and the appearance of mental retardation and cerebral calcifications. Loading tests with folic acid and its derivatives led to the conclusion that the folate deficiency was caused by a defect in folate transport both across the gut and the blood-brain barrier. Low plasma concentrations of methionine prompted a therapeutic trial with methionine associated with vitamin B12 and folic acid that spectacularly improved the convulsions.
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PMID:Congenital folate malabsorption. 398 28

The relationship between serum folate level and psychological disturbances was studied in a series of 95 chronic epileptic outpatients. All were nondrinkers. Serum folic acid in all cases and vitamin B12 in 83 cases were determined by radioimmunoassay. Only three factors were significantly related with psychological disturbances: serum levels of folic acid were significantly lower and the mean corpuscular volume of the erythrocytes was significantly higher in disturbed patients, particularly in those with the most severe psychiatric syndromes, and the incidence of disturbances was significantly higher in patients treated with three or more drugs. Conversely, variables such as number or type of seizures, duration of epilepsy, duration of treatment, presence of structural neurological lesions, previous mental retardation, or focal temporal lobe disturbances in the EEG did not show any statistical relationship to the presence of psychological disturbances. No relevant relationship was found between serum vitamin B12 and psychological disturbances.
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PMID:Psychological disturbances and folic acid in chronic epileptic outpatients. 661 89

Two siblings (4 and 10 years old) with ichthyosis vulgaris, growth and mental retardation, hair dysplasia, teeth abnormalities, recurrent infections and malabsorption are presented. The elder sister of the children as well as the rest of the family are unremarkable. The complex of symptoms does not fit into one of the known Ichthyosis syndromes. Microscopically the dystrophic hairs show changes in diameters, nodules, lack of the medulla, rough cuticle and splits vertical to the axis, sometimes resembling trichorrhexis nodosa. In the scanning electron-microscope there is a clear difference to Netherton's syndrome. The plasma concentrations of the vitamines A, B12 as well as of beta-carotines are low in spite of normal nutrition. During parenteral therapy with vitamin A and B12 symptoms ameliorate slightly.
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PMID:[Ichthyosis vulgaris, growth retardation, hair dysplasia, tooth abnormalities, immunologic deficiencies, psychomotor retardation and resorption disorders. Case report of 2 siblings]. 722 65

Homocyst(e)ine [H(e)], the sum of homocysteine, homocystine, and the homocysteine-cysteine mixed disulfide, free and protein-bound, has been shown to be associated in retrospective case control studies, and in one prospective study, with vascular disease, including coronary artery disease (CAD), cerebrovascular disease, and peripheral vascular disease. Elevated levels of homocyst(e)ine severe enough to cause homocystinuria are seen in severe nutritional deficiencies of vitamin B12, folic acid and vitamin B6. Rare genetic disorders of vitamin B12 synthesis of 5'-10'-methylene tetrahydrofolate reductase, or the pyridoxal phosphate-dependent enzyme cystathionine beta-synthase may cause severe hyperhomocyst(e)inemia and homocystinuria. The clinical manifestation of these disorders are mental retardation, neurological disorders, and widespread thromboembolic phenomena. The measurement of H(e) is currently performed using high-pressure liquid chromatography with fluorescence detection. Other methods, especially mass spectroscopy, are also used. Internal standards using increasing concentrations of homocystine and acetylcysteine and several external standards are used to ensure accuracy of the assay. Milder elevations of H(e) have recently been associated with vascular disease, in both men and women. The strength of this association appears to be stronger for peripheral and cerebrovascular disease than for CAD. Nevertheless, several case control studies in Europe, Canada, and the United States have shown that H(e) levels are elevated in CAD patients compared with controls, and H(e) levels are independent of the conventional cardiovascular risk factors (age, gender, lipid and lipoprotein cholesterol levels, hypertension, or cigarette smoking). One prospective study, the Physicians' Health Study, has shown that H(e) levels are slightly but significantly higher in CAD cases vs controls in a population of US physicians.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Measurement of homocyst(e)ine in the prediction of arteriosclerosis. 762 74

We performed a retrospective study of all patients with methylmalonic acidemia diagnosed during the past 20 years. Only those patients who were nonresponsive to vitamin B12 in vivo and in vitro were included. The final study group consisted of 26 patients, of whom 16 had a neonatal (early) onset; in 10 patients the diagnosis was made after 2 months to 2.2 years (late onset). Of the early-onset patients, 14 (87%) died, with a mean survival time of 1.5 years (range, 10 days to 2.5 years), whereas four of the late-onset patients (40%) died (range, 1.2 to 15 years). At present, eight patients are alive; their mean age is 4.6 years (range, 1 to 10 years). In the early 1970s, treatment was based on the principles of treating patients with phenylketonuria: restricting natural protein intake and supplementing essential amino acids, vitamins, and trace elements. After about 1980, nasogastric tube feeding became a mainstay of the therapy, natural protein restriction became stricter, and the use of essential amino acid mixtures diminished. Carnitine was added to the therapy and, in later years, metronidazole. Since these changes were implemented, the number of episodes of metabolic decompensation and hospitalizations has decreased. Mean survival time of the patients, in particular those with early onset, has only slightly improved, partly because of psychosocial problems in many of these families. Almost all the patients, especially those with early onset, had some degree of neurologic impairment and mental retardation, and many patients were at less than 2 SD for weight or height or both. In contrast, the neurologic and mental status of the late-onset patients was frequently normal, and their weight and height were more often within normal limits. Our results show that the treatment of methylmalonic acidemia still poses considerable problems; despite intense medical efforts and familial stress, the prognosis for the early-onset patients is disappointing. The patients with late-onset disease, however, appear to have a fairly good prognosis with the present therapeutic approach. Liver transplantation or possibly genetic therapy might improve our results in the future.
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PMID:Clinical outcome of long-term management of patients with vitamin B12-unresponsive methylmalonic acidemia. 799 62

Familial hereditary ventricular hypertrophy (HCM) is classified as a genetically determined disease (autosomal dominant trait) characterized by generalized ventricular hypertrophy, specific heart sounds and echocardiography images, characteristic ECG changes. Sudden death occurs in some cases. Clinical data and laboratory findings in a family of twelve, in which three brothers (aged 17, 21 and 25) displayed typical features of hypertrophic cardiomyopathy, are presented. In addition to the HCM symptoms, all brothers displayed unique, characteristic phenotype: long upper and lower extremities, microcephaly and different in degree mental retardation. Echocardiography and Holter monitoring revealed types III and IV (according to Maron's classification) with complex ECG disturbances. In other members of the family the following changes were found: supra and ventricular arrhythmias appeared in the ECG of the mother (45 years old) in the forth decade of her life and ST disturbances ("silent ischaemia") in the ECG of the father (44 years old). Arrhythmias were present in the father's brother and sister, but without any clinical signs of HCM. Cytogenetic analysis was performed on the peripheral blood lymphocytes derived from the mother and all her sick sons--the karyotypes were normal. Additional cytogenetic studies detecting the presence of chromosome fra (16) were negative. Analyses of the HLA antigens were performed on 13 members of the three generations in the family. The HLA antigens of classes I-A, B and C were identified and results suggest some linkage between HCM and B12 (44) antigen. To our knowledge, the present study provides the first description of a family displaying simultaneously ventricular hypertrophy and a specific phenotype with mental retardation.
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PMID:[Hypertrophic cardiomyopathy occurring in the family. Rare coexistence with oligophrenia. Clinical examinations, cytogenetic and HLA system]. 823 Oct 10


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