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)

Norrie disease is a rare X-linked recessive disorder characterized by blindness from infancy. The gene for Norrie disease has been localized to Xp11.3. More recently, the genes for monoamine oxidase (MAOA, MAOB) have been mapped to the same region. This study evaluates the clinical, biochemical, and neuropsychiatric data in an affected male and 2 obligate heterozygote females from a single family with a submicroscopic deletion involving Norrie disease and MAO genes. The propositus was a profoundly retarded, blind male; he also had neurologic abnormalities including myoclonus and stereotopy-habit disorder. Both obligate carrier females had a normal IQ. The propositus' mother met diagnostic criteria for "chronic hypomania and schizotypal features." The propositus' MAO activity was undetectable and the female heterozygotes had reduced levels comparable to patients receiving MAO inhibiting antidepressants. MAO substrate and metabolite abnormalities were found in the propositus' plasma and CSF. This study indicates that subtle biochemical and possibly neuropsychiatric abnormalities may be detected in some heterozygotes with the microdeletion in Xp11.3 due to loss of the gene product for the MAO genes; this deletion can also explain some of the complex phenotype of this contiguous gene syndrome in the propositus.
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PMID:Clinical, biochemical, and neuropsychiatric evaluation of a patient with a contiguous gene syndrome due to a microdeletion Xp11.3 including the Norrie disease locus and monoamine oxidase (MAOA and MAOB) genes. 130 52

The authors describe two series of patients: 12 treated simultaneously with fluoxetine and a monoamine oxidase inhibitor and 6 patients started on treatment with an MAOI 10 days or more after stopping fluoxetine treatment. All patients had extremely refractory depression and were treated in open fashion before general knowledge was obtained of the side effects that may accompany the fluoxetine-MAOI combination. During the fluoxetine-MAOI trial, most patients continued to receive other psychotropic combinations that had been partially helpful. The use of fluoxetine and an MAOI, either together or in close succession, was accompanied by a very high incidence of adverse effects, especially the "serotonergic syndrome." This syndrome was characterized by mental status changes, such as hypomania and confusion, and physical symptoms, such as myoclonus, hypertension, tremor, and diarrhea. Because of the high incidence of side effects and the lack of definite efficacy, the concurrent use of fluoxetine and MAOIs should generally be avoided. The long half-lives of fluoxetine and norfluoxetine, as well as the prolonged metabolic effects of MAOIs, may also dispose patients to an interaction if one of the drugs is started soon after stopping the other.
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PMID:Adverse consequences of fluoxetine-MAOI combination therapy. 199 42

In animals the occurrence of a behavioural syndrome consisting of hyperactivity, stereotyped movements and increase of temperature has been induced by MAOIs, 5-HT precursors (L-tryptophan) and 5-HT reuptake inhibitors. Most of these manifestations were specifically blocked by a pretreatment with an inhibitor of serotonin synthesis. In humans, the association of myoclonus, diarrhea, confusion, hypomania, agitation, hyperreflexia, shivering, incoordination, fever and diaphoresis, when patients are treated with serotoninergic agents, could constitute a "serotonin syndrome". Such cases of serotonin syndrome were reported after treatments with L-tryptophan, MAOIs, serotonin reuptake inhibitors and tricyclics alone or in association. The authors prospectively evaluated all the "serotonin-related" symptoms in 38 depressed inpatients fulfilling DSM III-R criteria of major depression. 16 (42%) out of 38 patients presented at least one symptom of serotonin syndrome. In 14 cases tremor and myoclonus occurred simultaneously and 10 patients presented at the same time tremor, myoclonus, diaphoresis and shivering. Except for two patients, symptoms were transient, lasted less than one week and disappeared with the pursuit of the treatment. Most often, serotonin syndrome thus corresponds to a reaction induced by a combination of serotoninergic agents at high dosages. In very rare cases, a toxic and potentially fatal interaction can occur between MAOIs, tricyclics and selective serotonin reuptake inhibitors at therapeutic dosages. Serotonin syndrome also provides an heuristic model of the putative mode of action of antidepressants. Serotonin-related symptoms are the physical and objective expression of the antidepressant-induced increase in serotonin. The specificity of serotonin-related syndrome also needs to be discussed since most of the symptoms, such as tremor and diaphoresis, are not in all cases related to an increase in serotonin.
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PMID:[The serotonin syndrome: review of the literature and description of an original study]. 852 62

Serotonin syndrome, a condition with numerous clinical neurological manifestations, is the result of central serotonergic hyperstimulation. Features of the syndrome include mental status and behavioral changes (agitation, excitement, hypomania, obtundation), motor system involvement (myoclonus, hemiballismus, tremor, hyperreflexia, motor weakness, dysarthria, ataxia) and autonomic symptoms (fever, chills, diarrhea). Serotonin syndrome has been reported exclusively in patients on medications for psychiatric illness and Parkinsonism, despite the fact that the putative action of many antimigraine agents also involves the serotonin system. We herein report six patients with migraine who developed symptoms suggestive of the serotonin syndrome. Five were taking one or more serotomimetic agents for migraine prophylaxis (sertraline, paroxetine, lithium, imipramine, amitriptyline). In each case the symptoms and signs developed in close temporal proximity with use of a migraine abortive agent known to interact with serotonin receptors. In three instances the agent was subcutaneous sumatriptan and, in three, intravenous dihydroergotamine. In each instance the symptoms were transient and there was full recovery. With the ever increasing use of migraine medications active at serotonin receptor sites, cases of serotonin syndrome will likely occur more frequently. It is important that physicians treating migraine are aware of the serotonin syndrome and are able to recognize its varying presentations.
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PMID:Serotonin syndrome complicating migraine pharmacotherapy. 886 67

Lithium has been used effectively used in the management of mood disorders, such as bipolar disease, acute mania, and hypomania. As the therapeutic index is very narrow for lithium, it is important to monitor lithium levels periodically to avoid toxic effects. Common toxic effects include diarrhea, tremor, muscle weakness, ataxia, and myoclonus. Severe toxicity can present with seizures, coma, and death. Cardiotoxicity secondary to lithium is rarely reported in the medical literature and can range from dysrhythmias and cardiomyopathies to myocardial infarction. We describe an interesting case report of cardiac toxicity secondary to lithium in a bipolar patient managed conservatively in an intensive care setting.
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PMID:Lithium-induced Cardiotoxicity: A Rare Clinical Entity. 3278 90