Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0013421 (dystonia)
 8,418 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Extrapyramidal features may occur in spinocerebellar ataxias consistent with neuropathological evidence of nigrostriatal involvement. Recently, striatal dopaminergic neurotransmission was found to be abnormal in the uncommon parkinsonian presentation of spinocerebellar ataxia type 2 (SCA2). We have investigated, therefore, striatal dopamine transporter and D2 receptor function in a series of 9 patients with the more common ataxic presentation of SCA2 using single photon emission computed tomography and beta-CIT as well as IBZM. Age-matched healthy subjects and patients with Parkinson's disease (PD) served as controls. All except 1 SCA2 patient exhibited slowness of limb movements without rigidity or rest tremor. In addition, cervical dystonia was present in 5 and dystonic head tremor in 2 SCA2 patients. Striatocerebellar (S/C) ratios of beta-CIT binding were significantly reduced in SCA2 patients compared to control subjects, and they were within the range of PD patients. S/C ratios of IBZM binding were significantly reduced in SCA2 patients compared to control subjects. We conclude that dopaminergic neurotransmission is impaired in the ataxic presentation of SCA2, with a prominent loss of striatal dopamine transporter function. Both slowness of limb movements as well as dystonia in the ataxic SCA2 phenotype may reflect dysfunction not only at cerebellar but also at basal ganglia level.
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PMID:Abnormalities of dopaminergic neurotransmission in SCA2: a combined 123I-betaCIT and 123I-IBZM SPECT study. 1539 3

Eighteen patients from three large multigenerational families with genetically established spinocerebellar ataxia type 2 (SCA2) were examined, with special attention to the presence of dystonic features. Cervical dystonia (CD) was diagnosed according to standardised clinical criteria. CD was scored using the Tsui score. Polymyography was performed in six cases using bilateral surface electrode recordings of the sternocleidomastoid and trapezius muscles together with needle electrode recordings of the splenius capitis muscles bilaterally. CD was found in 11 of 18 patients (61%), and was the presenting symptom in one case. Severity of CD was mild to moderate, with Tsui scores ranging from 5 to 12 points. Polymyography in 6 of 11 SCA2 patients with CD showed the typical pattern of dystonia with spontaneous, involuntary muscle activation at rest in at least one neck muscle with disturbed reciprocal inhibition of antagonistic neck muscles. CD appears to be a common clinical feature in SCA2 and may precede ataxia and gait disturbance. By contrast, none of the 18 patients had dystonic features in other body regions. CD has probably been underreported in patients with the ataxic SCA2 phenotype and should be considered as an additional clinical manifestation in patients with hereditary ataxia.
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PMID:Cervical dystonia in spinocerebellar ataxia type 2: clinical and polymyographic findings. 1722 Feb 91

Transcranial sonography (TCS) identifies basal ganglia alterations in extrapyramidal movement disorders such as Parkinson's disease or dystonia. Although only rarely reported, TCS also reveals signal alterations of basal ganglia in several forms of hereditary and nonhereditary ataxia. Here, the examination procedure and its diagnostic value for the classification of ataxia are reviewed. Three TCS studies reported hyperechogenicity of substantia nigra (SN) as a frequent finding in spinocerebellar ataxia type 2, type 3, and type 17, indicating a vulnerability of the nigrostriatal system in SCA patients. A new "cerebellar examination plane" was proposed, allowing better visualization of fourth ventricle enlargement and nucleus dentatus hyperechogenicity as a characteristic finding in SCA3 patients. In sporadic Creutzfeldt-Jakob disease, a blurry inhomogeneous hyperechogenic signal pattern of lentiform nucleus was identified in all of the patients in a small case series. Furthermore, distinct bilateral hyperechogenicity of pallidostriatal regions have been described as a novel diagnostic feature in the sonographic differentiation of extrapyramidal and atactic movement disorders. TCS is a commonly available, noninvasive, and inexpensive diagnostic tool, which provides reliable information about the morphology of the brain in ataxias, even in agitated patients who do not tolerate other imaging techniques. Further neuropathological and multimodal imaging studies are needed to elucidate the precise morphological and pathogenetic background of the detected echosignal pathology, and also to correlate these findings to the various clinical features of this disease entity.
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PMID:Transcranial sonography in ataxia. 2069 5

We report a 50-year-old woman with an unremarkable birth and developmental history, and with no family history of neurological disorders. The patient had a 6-year history of progressive cervical dystonia, oral dyskinesia, and hyperreflexia. She was initially considered to have spastic paraparesis of unknown cause. Because brain MRI showed mild atrophy of the cerebellar vermis, genetic analysis for spinocerebellar ataxia types 1, 2, 3, 6, 7, 8, 12, and 17, and dentatorubral-pallidoluysian atrophy was performed. The results revealed an abnormal expansion of CAG repeats (38 repeats) in one allele of ATXN2, and the patient was diagnosed with spinocerebellar ataxia type 2 (SCA2). She had no major clinical features of SCA2 such as cerebellar ataxia, slow saccade, or hyporeflexia. Recent reports have shown the CAG repeat expansion in ATXN2 to be detected in patients with familial L-dopa-responsive parkinsonism. The present case suggests that CAG repeat expansion in ATXN2 may be detected in some patients with spastic paraparesis, and that wide variations of clinical manifestations exist in SCA2.
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PMID:[A case of spinocerebellar ataxia type 2 presenting with a clinical course similar to spastic paraparesis]. 2096 Sep 29