Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0016719 (Friedreich's ataxia)
 2,098 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The authors report a clinical review of 16 childhood cases with early-onset cerebellar ataxia with retained tendon reflexes. The preservation of tendon reflexes distinguishes this disorder from Friedreich's ataxia. The mean age of onset of symptoms was 7.1 years. The main presenting symptom was abnormal gait (100%). Ataxia of gait and limbs and normal or increased tendon reflexes were found in all cases. This disorder is associated with dysarthria, pyramidal signs in the limbs, and in some instances, sensory loss. Other important differences from Friedreich's ataxia are absence of optic atrophy, diabetes mellitus, cardiomyopathy and severe skeletal deformity. Sensory nerve conduction was found to be normal, excluding one case. This finding constitutes another aspect of the syndrome different from Freidreich's ataxia. CT scans were normal in 2 of the 4 cases. The remaining two cases showed cerebellar atrophy. Inheritance is probably autosomal recessive in the majority of cases.
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PMID:Early-onset cerebellar ataxia with retained tendon reflexes. 261 87

The authors report the clinical review of 20 childhood cases with Friedreich's ataxia. The mean age at onset of symptoms was 6.1 years. The main presenting symptom was abnormal gait (100%). Ataxia of gait and limbs and depressed or absent tendon reflexes were found in all cases. Clinical findings are in accordance with the findings of Harding and Werdelin. Neurophysiological studies (especially sensory) are important in the confirmation of the diagnosis. Of the 10 cases in which sensory nerve conduction velocity measurements were performed, 7 had absent sensory action potentials, 2 had decreased potentials and one was normal. In our study, it is shown that in patients having ataxic gait, ataxia of limbs and tendon reflexes depression or loss, Friedreich's ataxia may be diagnosed with the help of electrophysiological studies.
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PMID:Friedreich's ataxia: a clinical review of 20 childhood cases. 340 87

Friedreich's ataxia (FRDA) is the most frequent cause of recessive ataxias. Neurological examination shows oculo-motor ataxia, dysarthria, limbs ataxia, tendon areflexia, pyramidal signs and sensory deficits. Extra-neurological involvement consists in osteoarticular deformities, cardiomyopathy and diabetes mellitus. Neurological deficits and osteoarticular deformities both contribute to the gait disorder, which is the main disabling deficit. In 98% of the cases, a trinucleotide repeat is found in chromosome 9. Gene implicated in FRDA codes for a protein called frataxin. Experimental studies have revealed iron accumulation in mitochondria of neurons and cardiomyocytes, suggesting that frataxin plays a determinant role in intramitochondrial iron homeostasis. These discoveries are now considered as a clue for new strategies of treatment in this hereditary disease.
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PMID:[Friedreich's ataxia: recent developments and prospects for treatment]. 1033

A 55-year-old woman presented with a 10-yeai history of a progressive gait disorder. Her examination showed a spastic paraparesis with brisk deep tendon reflexes, but only minimal limb ataxia and no evidence for a sensory neuropathy The patient was found to be homozygous for the GAA trinucleotide repeal diagnostic of Friedreich's ataxia The presentation of Friedreich's ataxia as a spastic paraparesis reinforces the appreciation of the variable phenotype of this disease.
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PMID:Late-Onset Friedreich's Ataxia Presenting as a Spastic Paraparesis. 1907

Our aim was to perform a comprehensive analysis of the global and segmental features of gait in patients with genetically confirmed inherited ataxias. Sixteen patients with autosomal dominant (spinocerebellar ataxia, SCA1 or 2) or recessive (Friedreich's ataxia, FRDA) ataxia were studied. We used a motion analysis system to record gait kinematic and kinetic data. We measured the mean values of global (time-distance parameters, COM displacement, support moment) and segmental gait parameters (joint displacement and inter-joint coordination), as both discrete and continuous variables, and their variability and correlations with International Cooperative Ataxia Rating Scale (ICARS) scores. We found a marked difference in all global gait parameters between the ataxic patients and the controls and close correlations between longer stride and stance duration and lower gait, posture and total ICARS scores. The only difference between the two patient groups was a shorter step length in the FRDA patients. As regards the segmental features, we found a significantly different waveform shape for all continuous kinematic and kinetic measures between the ataxic patients and the healthy controls, but only minor differences for the discrete measures. Intersegmental coordination evaluated using the continuous relative phase method revealed an irregular alternating joint behaviour without clear evidence of the synchronous pattern of alternating proximal/distal joint seen in healthy subjects. For almost all gait parameters we observed a markedly higher intra-subject variability in the ataxic patients versus the controls, which was strongly related to the clinical ICARS scores. Patients with chronic, progressive inherited ataxias lose the ability to "stabilize" a walking pattern that can be repeated over time. The most peculiar aspect of the gait of inherited ataxia patients, regardless the different genetic forms, seems to be the presence of increased variability of all global and segmental parameters rather than an invariant abnormal gait pattern.
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PMID:Gait pattern in inherited cerebellar ataxias. 2171 29

Spinocerebellar ataxia in the Italian Spinone dog breed is characterised by a progressive gait abnormality that manifests from approximately 4 months of age. The disorder shows an autosomal recessive mode of inheritance, and affected individuals are usually euthanized by one year of age on welfare grounds due to an inability to ambulate. Using a homozygosity mapping technique with six cases and six controls, we mapped the disease locus to chromosome 20 of the canine genome. Linkage analysis across an extended pedigree confirmed the association, with microsatellite C20.374 achieving a maximal LOD score of 4.41. All five genes within the disease-associated interval were exon resequenced, although no exonic candidate mutations were identified. A targeted resequencing approach was therefore adopted to sequence the entire disease-associated interval. Analysis of the sequencing data revealed a GAA repeat expansion in intron 35 of ITPR1, which was homozygous in all cases and heterozygous in obligate carriers. Partial impairment of cerebellar ITPR1 expression in affected dogs was demonstrated by immunohistochemistry. Given the association of ITPR1 mutations with spinocerebellar ataxia (SCA) type 15 (also designated SCA16) in humans and that an intronic GAA repeat expansion has been shown to cause Friedreich ataxia, the repeat expansion is an excellent candidate for the cause of spinocerebellar ataxia in the Italian Spinone. This finding represents the first naturally occurring pathogenic intronic GAA repeat expansion in a non-human species and a novel mechanism for ITPR1 associated spinocerebellar ataxia.
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PMID:Spinocerebellar ataxia in the Italian Spinone dog is associated with an intronic GAA repeat expansion in ITPR1. 2535 48

The classic phenotype of Friedreich ataxia is characterized by dysarthria, progressive limb and trunk ataxia, loss of reflexes, and gait disturbance with the onset of disease before the second decade. Homozygous trinucleotide repeat expansion of GAA in the FXN gene is found in 98% of patients. Two-5% of all patients have a repeat expansion on one allele and a point mutation on the other allele. Atypical phenotype is found in 25% of patients. A 10-year-old boy presented with congenital biliary atresia and progressive gait abnormality. His examination was significant for spastic gait, hyperreflexia, and sensory neuropathy. Genetic testing revealed a compound heterozygous mutation in the FXN gene. The absence of dysarthria and ataxia, retention of reflexes, absence of diabetes, and variable development of cardiomyopathy support a slow progression of disease with compound heterozygous mutation at G130V. Missense mutations are rare causes of Friedreich ataxia that can only be detected by sequencing of the FXN gene. Sequencing of the FXN gene is essential to make an early diagnosis when there is an atypical phenotype.
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PMID:Atypical Presentation for Friedreich Ataxia in a Child. 2630 74