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Query: UMLS:C0004134 (ataxia)
 15,886 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Many neurological disorders have been described in combination with sensorineural hearing loss and pigmentary retinopathy. We present the clinicopathological case of such a combination, associated with premature atherosclerosis of large cerebral arteries. In the literature dealing with the combination of deafness and pigmentary retinopathy, none of the many described syndromes was associated with premature atherosclerosis. The mitochondrial myopathy, encephalopathy, lactic acidosis, early atherosclerosis and stroke-like episodes (MELAS) syndrome can include deafness and blindness. In this syndrome small cerebral arteries are affected. In our case we did not find electron microscopic evidence of mitochondrial myopathy. Also the syndrome with encephalopathy, deafness, blindness and ataxia in young women is attributed to microangiopathy with small brain infarcts and retinal infarcts. In contrast, in our case, large cerebral arteries are affected. In the reverse order, none of the conditions with early atherosclerosis has been reported in combination with sensorineural deafness and pigmentary retinopathy. There is some similarity of our case to cases of Usher syndrome, type II. In the Usher syndrome, plasma lipid disturbances have been described and neuroradiological evidence of decreased circulation in the posterior cerebral circulation has been published. We suggest that in cases of congenital or acquired oto-ophthalmo-neurological disease the cerebral circulation and the lipid metabolism should be analyzed.
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PMID:A congenital syndrome of mental deficiency, gait disturbance, sensorineural deafness and pigmentary retinopathy associated with premature atherosclerosis. 852 24

Two siblings (one man, one woman), presenting with diarrhea, severe weight loss peripheral neuropathy, ophthalmoparesis, asymptomatic leukoencephalopathy were diagnosed as a new cases of Mitochondrial Neuro Gastro Intestinal Encephalomyopathy syndrome (MNGIE). Hirano (1994) defined four criteria for the diagnostic: peripheral neuropathy, ophthalmoparesis, gastro intestinal dysmotility, muscle biopsy with histologic features of mitochondrial myopathy (ragged-red fibers, muscle fibers with increased succinate deshydrogenase stain or ultra structurally abnormal mitochondria). In a review of the literature, we found 31 cases with MNGIE. With our two cases, we study this group of 33 patients. First symptoms begin about 13.5 years with a median of 10 years and extremes for 1 to 32 years. The first signs are gastro intestinal symptoms (recurrent nausea, vomiting or diarrhea with intestinal dysmotility) in 22 cases, an ophthalmoparesia in 4 cases, intestinal and ocular signs in 1 case, gait ataxia or peripheral neuropathy in 3 cases, hearing loss in 1 case, gait ataxia or peripheral neuropathy in 3 cases, hearing loss in 1 case. During the evolution, besides the cardinal signs, the following features have been observed with a variable frequency: hearing loss, short stature, facial palsy, dysphonia, dysarthria, sweating, orthostatic hypotension, bladder dysfunction, hepatomegalia, The laboratory features are: abnormal Nerve Condition Studies/EMG compatible with a sensory motor neuropathy, lactic acidosis, mitochondrial respiratory chain defect (essentially complex IV deficiency, complex I deficiency or multiple complex defect), MRI leukodystrophy, elevated CSF protein, heart block, ragged-red fibers or increased SDH stain. The prognosis is poor, due to a severe weight loss bordering on cachexia 13 patients died with a mean age of 28.5 years (median 24 years, extreme 3 years to 51 years). The prognosis seems to be worsened by a young age of onset. The 33 patients belong to 19 families with 7 cases of consanguinity. 25 patients had a brother, a sister or a cousin affected. The study of these families is compatible with an autosomic recessive transmission, suggesting a pathology of the nuclear genomi, probably impliying the control of the mitochondrial DNA replication. In fact, in 13 cases, a study of the mt DNA was realized: multiple deletions were founded in 6 cases, multiples mutations in one case, unique mutation in 1 case. In 5 cases ther was no evidence of abnormality. These precise etiology and pathophysiologic significance of the mt DNA deletions, and the heterogeneity of the modifications of the mt DNA remain unknown. However, the possibility of various phenotypes for a same genotype or inversely is known in mitochondriopathies.
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PMID:[MNGIE syndrome in 2 siblings]. 968 18

A 55-year-old woman, who had two episodes of difficulty in putting a key into a keyhole probably due to optic ataxia at age 52 and 54 years old, developed speaking errors and was admitted to our hospital. She was 152.5 cm in height and 52.5 kg in weight. Neurological examination revealed right homonymous hemianopsia and sensory aphasia. A CSF examination revealed lymphocytic pleocytosis of 88/microliter. Serum lactate and pyruvate were remarkably increased after an aerobic exercise test. A few ragged-red fibers were present in the biopsied brachial biceps muscle. Brain MRI by FLAIR method showed scattered high signal lesions in the left temporal lobe, bilateral parieto-occipital lobes, left insular cortex and left thalamus. The left superficial temporal lesion was enhanced by gadolinium-DTPA. The proton MRS demonstrated the lactic acid peak as well as the decrease of NAA/choline ratio (0.38) in the left parieto-occipital region. Thus, she was diagnosed as a case of MELAS (mitochondrial myopathy, encephalopathy, lactic acidosis and stroke-like episodes) and successfully treated with ubidecarenone (150 mg/day). Six months later, she again developed seizure, right hemiparesis and deterioration of aphasia and presented again CSF lymphocytic pleocytoses of 15/microliter. Brain MRI demonstrated new lesions in the left temporoparietal lobes, left insular cortex and left corona radiata. Therefore, CSF pleocytosis appeared to be associated with stroke-like episodes in this case. Although the mechanism of CSF pleocytosis remains to be elucidated, it may involve the breakdown of blood-brain barrier caused by mitochondrial dysfunction. Otherwise, an inflammatory process similar to that in cases of Leber disease, who developed multiple sclerosis-like additional lesions in the central nervous system, may also take place in MELAS.
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PMID:[A case of MELAS showing CSF pleocytosis associated with stroke-like episodes]. 986 8

This report concerns an autopsy case of mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episodes (MELAS) with unusual neuropathological findings. The patient was a Japanese woman who was 21 years old at the time of death. Her mother is a patient with genetically confirmed MELAS. Her clinical manifestations included convulsions and lactic acidosis in the latter half of the first decade of life, followed by deafness, dementia, muscle weakness in the lower extremities, slight ataxia in the upper and lower extremities, and diabetes mellitus. Muscle biopsy revealed ragged-red fibers, and genetic study showed a point mutation at nucleotide pair 3243 in mitochondrial DNA. She died of lactic acidosis. In the clinical course, she did not develop stroke-like episodes. The neuropathological examination revealed not only minute to small necrotic foci in the cerebral cortex, amygdala, hippocampus, and cerebellum, but also prominent white matter gliosis in the central nervous system and cerebellar cortical degeneration of granular cell type. Our neuropathological findings, including prominent white matter gliosis of the central nervous system and cerebellar cortical degeneration of granular cell type, may indicate morphologically widespread cellular dysfunction, not restricted to either neuronal or vascular derangement, in the brain pathology of MELAS.
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PMID:MELAS with prominent white matter gliosis and atrophy of the cerebellar granular layer: a clinical, genetic, and pathological study. 1033 91

Mitochondrial disorders are multisystem diseases with very heterogeneous clinical manifestations. Common cardiac features include cardiomyopathy and conduction defects. We report a five-year-old boy who presented with signs of congestive cardiac failure and was diagnosed to have dilated cardiomyopathy. Six months later, he developed progressively worsening ataxia, hypotonia, other cerebellar signs, hearing loss, severe sensory peripheral neuropathy and lactic acidosis. Electronmicroscopy of skeletal muscle biopsy was consistent with mitochondrial myopathy.
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PMID:Mitochondrial myopathy presenting as ataxia with dilated cardiomyopathy. 1137 Apr 43

We report a 67-year-old man with mitochondrial myopathy, encephalopathy, lactic acidosis and stroke-like episodes (MELAS), successfully treated with eicosapentaenoic acid ethyl ester (EPA-E) for about eight months. He showed bilateral auditory disturbance and slowly progressive gait ataxia at age 50 during treatment of diabetes mellitus (DM) with subcutaneous injection of insulin since age 29. At age 58 he manifested an acute hemiparesis of right extremities for one week with no abnormal findings on neuroradiological examinations. A permanent pacemaker was implanted at age 61 to treat frequent syncopal attacks due to complete atrioventricular block. On admission to our hospital, neurological examinations revealed dementia, auditory disturbance, severe cerebellar ataxia and mild atrophy of proximal muscles with systemic hyporeflexia. Based on a point mutation in position 3243 of mitochondrial DNA, he was diagnosed as having MELAS with severe DM, auditory disturbance and cardiac conduction block. After initiation of treatment with EPA-E at a dose of 2,700 mg/day he showed temporarily an improvement in auditory disturbance, blood glucose control and cerebellar ataxia. In objective evaluations for cerebellar ataxia, we could find significant decreases in times for 20 m walking and heel-knee patting in the ninth month, and in time for tracing of a whirl from the third to the ninth month, compared with those before treatment of EPA-E (p < 0.0001). Because EPA-E is taken into mitochondrial membranes and activates electron transmission enzyme complexes, it might be a candidate for therapy of mitochondrial encephalomyopathy, including MELAS.
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PMID:[A case of mitochondrial myopathy, encephalopathy, lactic acidosis and stroke-like episodes (MELAS), showing temporary improvement during the treatment with eicosapentaenoic acid ethyl ester]. 1199 86

We report an unusual case of encephalo-entero-myopathy associated with the A8344G mutation in the tRNA(Lys) gene of mitochondrial DNA (mtDNA). This patient had mitochondrial myopathy, multiple lipomatosis, mild hearing loss, stroke-like episodes, and paralytic ileus, but she lacked the canonical clinical features of MERRF, myoclonus, epilepsy, or ataxia. We conducted genetic, biochemical, histochemical, and immunohistochemical studies in skeletal muscle, brain, intestine, and lipoma tissue. The mutation was abundant in all tissues, and cytochrome c oxidase (COX) activity was selectively decreased in brain and small intestine. COX deficiency was also documented histochemically and immunohistochemically in the small intestine, suggesting that mitochondrial dysfunction played a role in the pathogenesis of paralytic ileus. This case illustrates an unusual and dramatic clinical phenotype of the A8344G mutation, characterized by stroke-like episodes and acute ileus.
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PMID:The A8344G mutation in mitochondrial DNA associated with stroke-like episodes and gastrointestinal dysfunction. 1247 64

The mitochondrial encephalomyopathies are chronic progressive disorders affecting predominantly the neuromuscular system. Symptoms are induced by insufficient energy supply resulting from a deficiency of oxidative phosphorylation. We studied one male and four female patients with genetically proven mitochondrial encephalomyopathy. Their ages ranged from 7 to 19 years (two with Kearns-Sayre syndrome, one patient with neuronal muscle weakness, ataxia, and retinitis pigmentosa syndrome, and two patients with mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episodes), using a retrospective study method. We studied the effect of creatine supplementation (0.08 g-0.35 g/kg body weight/day; 9 months to 4 years, 10 months) and measured skeletal muscle power analysis (bicycle ergometer). After creatine supplementation all patients demonstrated an increase in their maximum performance (W) (+4% - +30%; mean: +12.1%). These results indicate an improved aerobic oxidative function of mitochondria after creatine administration in patients with mitochondrial encephalomyopathies. Continuous physical exercise was improved to a greater extent than instantaneous activity.
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PMID:Effectiveness of creatine monohydrate in mitochondrial encephalomyopathies. 1265 21

The accumulation of multiple mitochondrial DNA (mtDNA) deletions in stable tissues is a distinctive feature of several autosomal disorders, characterized by Progressive External Ophthalmoplegia (PEO), ptosis, and proximal myopathy. At least three nuclear genes are responsible for these disorders: ANT1 and C10orf2 cause autosomal dominant PEO, while mutations of DNA polymerase gammaA (POLG1 or POLG) gene on chromosome 15q25 causes both autosomal dominant and recessive forms of PEO. To investigate the contribution of these genes to the sporadic cases of PEO with multiple mtDNA deletions, we studied 31 mitochondrial myopathy patients without any family history for the disorder: 23 had PEO with myopathy, with or without the additional features of pigmentary retinopathy, ataxia, neurosensorial hypoacusia and diabetes mellitus, 7 presented isolated myopathy and one a peripheral neuropathy with ptosis. In all patients Southern blot of muscle DNA showed multiple mtDNA deletions; screening for ANT1 and C10ORF2 genes was negative. POLG analysis revealed mutations in eight patients; in six of them the mutations were allelic, while two patients were heterozygous. Five mutations were new, namely one stop codon (c.2407C>T/p.R709X) and four missense mutations (c.1085G>C/p.G268A; c.1967G>A/p.R562Q; c.2702G>C/p.R807P; c.3076C>T/p.H932W). A high degree of conservation was observed for all the new missense mutations. Only patients presenting PEO as part of their clinical phenotype had POLG mutations, in seven of them together with myopathic signs and in one with a sensori-motor peripheral neuropathy.
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PMID:POLG mutations in sporadic mitochondrial disorders with multiple mtDNA deletions. 1463 18

We describe a young woman with a progressive mitochondrial myopathy that started with muscle weakness and went on to include deafness, dementia and ataxia. Skeletal muscle showed the histological and biochemical features of mitochondrial respiratory chain dysfunction. Genetic analysis identified a novel, heteroplasmic, A to G transition in tRNA(Ser(UCN)) at position 7480 affecting a highly conserved base in the anticodon loop. Single-fibre PCR showed highest levels of mutation in cytochrome c-oxidase-deficient fibres and quantification in two biopsies taken 5 years apart showed no change in percentage heteroplasmy. The mutation was present at lower levels in the patient's blood, but was not found in either her mother's or sister's blood and skeletal muscle, suggesting a sporadic occurrence. This is the eighth disease-causing mutation in this tRNA gene and confirms serine (UCN) as one of the most common sites for mtDNA mutation.
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PMID:Sporadic mitochondrial myopathy due to a new mutation in the mitochondrial tRNASer(UCN) gene. 1521 Jan 64


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