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)

Myoclonus, defined as shock-like involuntary movement, may be physiological or caused by a very wide variety of hereditary and acquired conditions. Because myoclonus can originate from different disorders and lesions affecting quite varied levels of the central and peripheral nervous systems, it represents from many points of view a diagnostic challenge. Moreover, new entities have been recently individualized, such as cortical tremor, which deserve renewed attention. The aim of this review is to propose a rationale for a diagnostic approach based on clinical and electrophysiological grounds. In this setting, we successively address 1) the clinical features allowing a positive diagnosis of myoclonus; 2) the clinical clues to the etiology; 3) the relevance of the clinical context to the diagnosis; and 4) the contribution of neurophysiology. Differentiating myoclonus from tics, spasm, chorea and dystonia can be difficult, and a careful reappraisal of clinical features allowing precise identification is presented. Moreover, the topographical distribution of myoclonus, the temporal pattern of muscle recruitment, the condition of occurrence and the rhythm of the event, may provide clinical clues relevant to the diagnosis. Myoclonus without associated epilepsy, myoclonus with epilepsy, myoclonus with encephalopathy, parkinsonism and/or dementia represent overlapping clinical categories, although they remain useful for the diagnostic approach. Using electrophysiology (including back-averaging EEG, MEG, SEP, C-reflex studies) to determine the origin of myoclonus may not allow us to focus on the underlying condition. Indeed, in many instances, the myoclonus is cortical in origin, but the pathology is found elsewhere.
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PMID:[Myoclonus in the adult: diagnostic approach]. 1128 Oct 67

A 23-year-old woman with a history of episodic stiffening of the limbs since her early adolescence, reported attacks of muscle contraction accompanied by feelings of panic but without loss of consciousness. Epileptic seizures, e.g. progressive myoclonic epilepsy, metabolic encephalopathy, dystonia and tetany were suggested. During the examination, muscle contraction could be provoked whilst measuring the blood pressure. Tetany based on primary hypoparathyroidism was diagnosed from the medical history as well as the neurological examination. This was confirmed by laboratory tests. She was successfully treated with calcium and I-alpha-(OH)2 vitamin D3.
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PMID:[Clinical thinking and decision making in practice. A young women with muscle cramps]. 1137 Apr 26

Glutaric aciduria typo I (GA I) is an uncommon metabolic disease with autosomal recessive inheritance. It usually presents in the first years of life and frequently causes movement disorders. Only a few cases have been diagnosed in adulthood. Two siblings who were diagnosed of GA I after a course of more than 20 years are reported here. The elder brother, after 9 months of normal psychomotor development, suffered from an acute encephalopathy with generalized hypotonia and, later on, dyskinetic movements. Throughout the following years severe generalized dystonia developed. The younger brother presented at 16 months with acute encephalopathy, hypotonia and generalized choreoathetoid movements. Cranial computed tomography showed in both patients an slight enlargement of Silvian cisures and diffuse white matter hypodensities. Magnetic resonance imaging performed in the second case disclosed in addition bilateral hyperintensities in putamen and caudate nucleous. At 29 and 24 years of age, respectively, an increased urinary excretion of glutaric and 3-hydroxiglutaric acids was detected in both patients. Glutaryl-CoA deshidrogenase activity in fibroblasts was absent in both. The patients were treated with carnitine and riboflavine, with no response. The present report shows that diagnosis of GA I should be considered in adults presenting a range of movement disorders from childhood.
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PMID:[Glutaric aciduria type I: diagnosis in adulthood and phenotypic variability]. 1173 16

The mitochondrial cytopathies are genetically and phenotypically heterogeneous group of disorders caused by structural and functional abnormalities in mitochondria. To the best of our knowledge, there are very few studies published from India till date. Selected and confirmed fourteen cases of neurological mitochondrial cytopathies with different clinical syndromes admitted between 1997 and 2000 are being reported. There were 8 male and 6 female patients. The mean age was 24.42+/-11.18 years (range 4-40 years). Twelve patients could be categorized into well-defined syndromes, while two belonged to undefined group. In the defined syndrome categories, three patients had MELAS (mitochondrial encephalopathy, lactic acidosis and stroke like episodes), three had MERRF (myoclonic epilepsy and ragged red fibre myopathy), three cases had KSS (Kearns-Sayre Syndrome) and three were diagnosed to be suffering from mitochondrial myopathy. In the uncategorized group, one case presented with paroxysmal kinesogenic dystonia and the other manifested with generalized chorea alone. Serum lactic acid level was significantly increased in all the patients (fasting 28.96+/-4.59 mg%, post exercise 41.02+/-4.93 mg%). Muscle biopsy was done in all cases. Succinic dehydrogenase staining of muscle tissue showed subsarcolemmal accumulation of mitochondria in 12 cases. Mitochondrial DNA study could be performed in one case only and it did not reveal any mutation at nucleotides 3243 and 8344. MRI brain showed multiple infarcts in MELAS, hyperintensities in putaminal areas in chorea and bilateral cerebellar atrophy in MERRF.
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PMID:Neurological mitochondrial cytopathies. 1213 80

Inherited metabolic disorders can cause onset of epilepsy in the first year of life. Epilepsy rarely dominates the clinical presentation, which is more frequently associated with other neurologic symptoms, such as mental retardation, hypotonia and/or dystonia, or vigilance disturbances. The pathogenesis of seizures is multifaceted; inherited metabolic disorder can affect the balance between excitatory and inhibitory chemical mediators, eliminate an energetic substrate at the cerebral level, cause in utero brain malformation, or provoke acute brain lesions. Some clinical disorders that strongly suggest particular metabolic etiologies can be identified. For example, specific clinical signs and findings on electroencephalogram (EEG) are characteristic of pyridoxine-dependent seizures, and inherited metabolic disorders associated with early myoclonic encephalopathy are well defined. In most cases, however, epilepsy secondary to inherited metabolic disorders presents with polymorphic clinical and EEG features that are difficult to classify into precise epileptic syndromes. Common characteristics of these seizures include onset in the first months of life; usually partial, multifocal; simple partial motor semiology; successive appearance of tonic seizures, spasms, and massive myoclonus; and resistance to antiepilepsy drugs. Inherited metabolic disorders must be considered in patients presenting with epilepsy and progressive neurologic worsening.
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PMID:Infantile epileptic syndromes and metabolic etiologies. 1259 51

Mutations in the MECP2 (methyl-CpG-binding protein 2) gene are known to cause Rett syndrome, a well-known and clinically defined neurodevelopmental disorder. Rett syndrome occurs almost exclusively in females and for a long time was thought to be an X-linked dominant condition lethal in hemizygous males. Since the discovery of the MECP2 gene as the cause of Rett syndrome in 1999, MECP2 mutations have, however, also been reported in males. These males phenotypically have classical Rett syndrome when the mutation arises as somatic mosaicism or when they have an extra X chromosome. In all other cases, males with MECP2 mutations show diverse phenotypes different from classical Rett syndrome. The spectrum ranges from severe congenital encephalopathy, mental retardation with various neurological symptoms, occasionally in association with psychiatric illness, to mild mental retardation only. We present a 21-year-old male with severe mental retardation, spastic tetraplegia, dystonia, apraxia and neurogenic scoliosis. A history of early hypotonia evolving into severe spasticity, slowing of head growth, breathing irregularities and good visual interactive behaviour were highly suggestive of Rett syndrome. He has a de novo missense mutation in exon 3 of the MECP2 gene (P225L). The clinical spectrum and molecular findings in males with MECP2 mutations are reviewed.
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PMID:Neurodevelopmental disorders in males related to the gene causing Rett syndrome in females (MECP2). 1261 69

Movement disorders or basal ganglia injury have not been reported as complications of the ketogenic diet, an alternative treatment for intractable epilepsy. We report on a novel complication of the ketogenic diet manifesting as a severe extrapyramidal movement disorder and bilateral putaminal lesions. A single case is described. A video demonstrating the movement disorder is included. A 5-year-old girl with a cryptogenic epileptic encephalopathy developed focal dystonia, diffuse chorea, and ataxia after starting the ketogenic diet. Cranial magnetic resonance imaging (MRI) demonstrated bilateral putaminal lesions that were not present before starting the diet. MR spectroscopy showed a lactate peak in the basal ganglia, suggesting a failure of mitochondrial energy metabolism as the mechanism of cerebral injury. The radiographic abnormalities resolved after stopping the diet, although the movement disorder persisted. Basal ganglia injury and extrapyramidal movement abnormalities are potential complications of the ketogenic diet. Concomitant use of valproate or a latent inborn error of metabolism may be risk factors for these rare complications.
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PMID:Basal ganglia injury as a complication of the ketogenic diet. 1267 55

We identified the IgG autoantibody ANNA-2 ("anti-Ri") in 34 patients in a 12-year period by immunofluorescence screening of sera from approximately 75000 patients with subacute neurological disorders that were suspected to be paraneoplastic. Detailed clinical information was available for 28 patients (10 men, 18 women). Cancer was diagnosed in 24 patients (86%); 21 had histologically proven carcinoma (10 lung, 9 breast, 1 cervical, 1 bladder), and 3 had an intrathoracic imaging abnormality. Cancer anteceded neurological symptoms in 4 of 28 patients. Cancer detection frequency increased with continued surveillance. Neurological disorders, in decreasing frequency, were brainstem syndrome (including opsoclonus, myoclonus, or both), cerebellar syndrome, myelopathy, peripheral neuropathy, cranial neuropathy, movement disorder, encephalopathy, Lambert-Eaton syndrome, and seizures. Four patients had laryngospasm and four had jaw opening dystonia (two with neck dystonia). Nine (32%) were wheelchair-bound 1 month after neurological symptom onset. Most improved neurologically after immunomodulatory or tumor-directed therapy. Accompanying autoantibodies, found in 73% of sera, included ANNA-1, ANNA-3, CRMP-5-IgG, P/Q-type and N-type Ca(2+) channel antibodies, and muscle-type acetylcholine receptor antibody. Some neurological accompaniments of ANNA-2 may reflect potentially pathogenic humoral or cell-mediated responses to coimmunogenic tumor antigens, for example, Lambert-Eaton syndrome (P/Q-type Ca(2+) channel antibody) and peripheral neuropathy (ANNA-1 effector T cells).
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PMID:Anti-neuronal nuclear autoantibody type 2: paraneoplastic accompaniments. 1273 Sep 91

Tyrosine hydroxylase (TH) is the key enzyme in the biosynthesis of the catecholamines dopamine, epinephrine, and norepinephrine. Recessively inherited deficiency of TH was recently identified and incorporated into recent concepts of genetic dystonias as the cause of recessive Dopa-responsive dystonia or Segawa's syndrome in analogy to dominantly inherited GTP cyclohydrolase I deficiency. We report four patients with TH deficiency and two with GTP cyclohydrolase I deficiency. Patients with TH deficiency suffer from progressive infantile encephalopathy dominated by motor retardation similar to a primary neuromuscular disorder, fluctuating extrapyramidal, and ocular and vegetative symptoms. Intellectual functions are mostly compromised. Prenatally disturbed brain development and postnatal growth failure were observed. Treatment with levodopa ameliorates but usually does not normalize symptoms. Compared with patients with dominantly inherited GTP cyclohydrolase I deficiency, catecholaminergic neurotransmission is severely and constantly impaired in TH deficiency. In most patients, this results not in predominating dystonia, a largely nondegenerative condition, but in a progressive often lethal neurometabolic disorder, which can be improved but not cured by L-dopa. Investigations of neurotransmitter defects by specific cerebrospinal fluid determinations should be included in the diagnostic evaluation of children with progressive infantile encephalopathy.
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PMID:Tyrosine hydroxylase deficiency causes progressive encephalopathy and dopa-nonresponsive dystonia. 1470 30

A previously neurodevelopmentally intact 5-year-old male was admitted to hospital with a right lower lobe pneumonia with pleural effusion, subsequently confirmed to be a Mycoplasma pneumoniae infection. On the seventh day of the illness he had a prolonged generalized tonic or tonic-clonic convulsion, requiring intubation and ventilation. He was slow to regain consciousness (Child's Glasgow Coma Score 7-10 over 6 days) and brain imaging with CT and then MRI demonstrated bilateral thalamic lesions with oedema and central haemorrhage suggestive of acute bilateral thalamic necrosis, without striatal or white-matter involvement. He was treated with a 2-week course of erythromycin, and as an autoimmune process was considered possible, 5 days of intravenous methylprednisolone (20 mg/kg/day) followed by a 4-week oral prednisolone taper. He made a slow recovery over the next few weeks with almost complete neurological recovery by 2 months but with significant dysarthria, drooling, and a mild left hemiparesis. At 9 months, significant dystonia continued to affect his speech and, together with tremor, his upper-limb fine motor function bilaterally. His gait, personality, and higher cognitive functions appeared to have recovered fully. Although acute striatal necrosis, acute disseminated encephalomyelitis, and encephalitis have been reported with Mycoplasma pneumoniae and a similar picture of acute bilateral thalamic necrosis with influenza-A ('acute necrotizing encephalopathy'), this is the first reported case of Mycoplasma pneumoniae-associated isolated acute bilateral thalamic necrosis.
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PMID:Acute bilateral thalamic necrosis in a child with Mycoplasma pneumoniae. 1499 91


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