Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0027066 (myoclonus)
4,275 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A 44-year-old man suffered from repeated impairment of consciousness associated with flapping tremor, myoclonus and generalized convulsions, and died in coma 6 months after admission. He had had a psychosomatically underdeveloped childhood, with a propensity for legumes without a family history of the same or a record of consanguinity. On admission, he had disturbed consciousness and emaciation without other physical abnormalities. The EEG revealed diffuse slow waves with occasional appearance of triphasic waves. A high level of serum citrulline (534.7 nmol/ml) was recognized and the assay of urea cycle enzymes in the liver demonstrated decreased argininosuccinate synthetase (ASS) activity (0.062 U/g liver, 7.4% of that in normal liver), although no kinetic abnormality was found. Accordingly he was diagnosed as having type II citrullinemia. In addition, this case could be classified as cluster type of localization of the ASS in the liver by immunohistochemical study. There were characteristic findings concerning his clinical picture and laboratory data, such as a significant correlation between the grade of disturbed consciousness and arterial blood gas pH (r = 0.61, p less than 0.01). However, the blood ammonia level did not always correlate with the severity of disturbed consciousness. Oral treatment with sodium citrate and sodium benzoate was very effective, though transiently, for disturbed consciousness in this case. Pathological findings of the autopsied liver were fatty change and fibrosis. Neuropathologically, characteristic findings were brain edema with cerebellar tonsilar herniation, laminar necrosis with spongy formation in cerebral cortex, and Alzheimer type II glia. The relationship between citrullinemia and other hepatic encephalopathy was also discussed.
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PMID:[An autopsied case of type II citrullinemia--transient effectiveness with either citrate or benzoate to the consciousness disturbance]. 269 30

We have described several kinds of involuntary movements occurring in metabolic encephalopathies. They are often associated with slowing of electroencephalographic basic activities and with loss of consciousness. Laboratory studies disclose the cause of the encephalopathies. Asterixis, first reported in hepatic encephalopathy, is produced by EMG silence during voluntary contraction. Myoclonus is associated with a short excessive EMG discharges. Tremor is caused by grouping EMG discharges. Some other kinds of involuntary movements are seen in metabolic encephalopathies. Clinical features of hepatic, uremic, hypoxic, and hypoglycemic encephalopathies are briefly described.
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PMID:[Dyskinesia in metabolic encephalopathy]. 827 69

In a retrospective study of 15.326 EEGs performed from 1983 to 1992 in a psychiatric institute, 83 EEGs (62 patients-13 men and 49 women ranging in age from 59 to 90 years, with a mean age of 74 years) had triphasic waves (TWs). All 62 patients were awake, though they were often confused. Most (n = 56) had dementia, usually severe; 15 also had delirium. There were six nondemented patients (age range, 59-79 years, with a mean age of 67 years). Infrequent etiologies included neuroleptic malignant syndrome (n = 1) and hepatic encephalopathy (n = 1); in four, the cause was uncertain, although all were receiving lithium. EEG features analyzed included frequency of background rhythms, distribution of the TWs, periodicity, and epileptiform abnormalities. Background rhythms were slow in all but seven patients (mean, 6.2 +/- 1.7 [SD] Hz). TWs were maximal posteriorly in 47 patients and anteriorly in six and were diffuse in nine. Neuroimaging studies showed prominent posterior abnormalities in only one case. Periodicity was prominent in four patients; in two the TWs were maximal anteriorly. Interictal epileptiform activity was present in six, a history of seizures in eight, and myoclonus in four. TWs are uncommon in a psychiatric population; they occur primarily in elderly, severely demented patients. They are usually associated with background slowing, are often maximal posteriorly, and occasionally are periodic.
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PMID:Triphasic waves in a psychiatric population: a retrospective study. 885 94

We report a 47-year-old alcoholic man with alcoholic pellagra encephalopathy (APE) showing myoclonus and ataxia as chief complaints. He had been a heavy drinker for 30 years. He had noticed appetite loss and subsequently showed a subacutely progressive gait disturbance. He had no history of diarrhea, dementia, or dermatitis. On admission, he showed severe alcoholic liver cirrhosis with a large amount of ascites, limbs and truncal ataxia, myoclonus of the limbs and areflexia, although his consciousness was alert and there were no sign of dermatitis. Though the plasma level of ammonia was normal, we started administration of amino acids suspecting hepatic encephalopathy. Symptoms showed no improvement, and subsequent administration of thiamine was also ineffective. A decreased serum level of niacin was demonstrated. After administration of nicotinamide, the symptoms improved gradually. This patient received a diagnosis of APE. Endemic pellagra, characterized by the classical triad of dermatitis, diarrhea and dementia, is known to be caused by a dietary deficiency of the niacin, and has now become very rare in developed countries. At present, pellagra is encountered most often in patients with chronic alcoholism, which is called APE. APE patients often show only disturbance of consciousness. Although several reports has described ataxia and myoclonus in patients with APE, APE patients with myoclonus and ataxia as chief complaints have not previously been reported. On autopsy cases, central chromatolysis of neurons in the dentate nucleus of the cerebellum, gracile and cuneate nuclei, and the Clarke's column has been demonstrated. The APE patients would show myoclonus and ataxia as their first symptoms. In conclusion, we would like to emphasize that administration of niacin should be started for the treatment of chronic alcoholic patients showing myoclonus and ataxia even without the classical triads found in endemic pellagra patients.
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PMID:[A suspected case of alcoholic pellagra encephalopathy with marked response to niacin showing myoclonus and ataxia as chief complaints]. 1651 10

Hepatic encephalopathy is a common complication of hepatic cirrhosis. The clinical diagnosis is based on two concurrent types of symptoms: impaired mental status and impaired neuromotor function. Impaired mental status is characterized by deterioration in mental status with psychomotor dysfunction, impaired memory, and increased reaction time, sensory abnormalities, poor concentration, disorientation and coma. Impaired neuromotor function include hyperreflexia, rigidity, myoclonus and asterixis. The pathogenesis of hepatic encephalopathy has not been clearly defined. The general consensus is that elevated levels of ammonia and an inflammatory response work in synergy to cause astrocyte to swell and fluid to accumulate in the brain which is thought to explain the symptoms of hepatic encephalopathy. Acetyl-L-carnitine, the short-chain ester of carnitine is endogenously produced within mitochondria and peroxisomes and is involved in the transport of acetyl-moieties across the membranes of these organelles. Acetyl-L-carnitine administration has shown the recovery of neuropsychological activities related to attention/concentration, visual scanning and tracking, psychomotor speed and mental flexibility, language short-term memory, attention, and computing ability. In fact, Acetyl-L-carnitine induces ureagenesis leading to decreased blood and brain ammonia levels. Acetyl-L-carnitine treatment decreases the severity of mental and physical fatigue, depression cognitive impairment and improves health-related quality of life. The aim of this review was to provide an explanation on the possible toxic effects of ammonia in HE and evaluate the potential clinical benefits of ALC.
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PMID:Acetyl-L-carnitine in hepatic encephalopathy. 2338 20

Hepatic encephalopathy (HE) is a complex syndrome of neurological and psychiatric signs and symptoms that is caused by portosystemic venous shunting with or without liver disease irrespective of its etiology. The most common presentation of Wilson disease (WD) is liver disease and is frequently associated with a wide spectrum of neurological and psychiatric symptoms. The genetic defect in WD leads to copper accumulation in the liver and later in other organs including the brain. In a patient presenting with Wilsonian cirrhosis neuropsychiatric symptoms may be caused either by the metabolic consequences of liver failure or by copper toxicity. Thus, in clinical practice a precise diagnosis is a great challenge. Contrary to HE in neurological WD consciousness, is very rarely disturbed and pyramidal signs, myoclonus dominate. Asterixis and many other clinical symptoms may be present in both disease conditions and are quite similar. However details of neurological assessment as well as additional examinations could help in differential diagnosis.
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PMID:Encephalopathy in Wilson disease: copper toxicity or liver failure? 2604 65

Metabolic encephalopathies (ME) are a common cause of admission to emergency rooms, to hospitalization wards or to intensive care units. They could account for 10 to 20% of causes of comatose states in ICU and could be associated to a poor outcome especially in older patients. Nevertheless, they are often reversible and are associated with a favorable outcome when diagnosed and rapidly treated. They correspond to an altered brain functioning secondary to the deficiency of a substance that is mandatory for the normal brain functioning or to the accumulation of a substance that can be either endogenous or exogenous. It preferably occurs in co-morbid patients, complicating its diagnosis and its management. Altered brain functioning, going from mild neuropsychological impairment to coma, movement disorders especially myoclonus and the absence of any obvious differential diagnosis are highly suggestive of the diagnosis. Whereas some biological samplings and brain MRI are essential to rule out differential diagnosis, some others, such as electroencephalogram, may be able to propose important clues in favor of the diagnosis. Once simple symptomatic measures are introduced, the treatment consists mainly in the correction of the cause. Specific treatment options are only seldom available for ME; this is the case for hepatic encephalopathy and some drug-induced encephalopathies. We will successively describe in this review the main pathophysiological mechanisms, the main causes, favoring circumstances of ME, the differential diagnosis to rule out and the etiological work-up for the diagnosis. Finally, a diagnostic and therapeutic strategy for the care of patients with ME will be proposed.
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PMID:[Metabolic encephalopathies]. 3063 3