Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P00492 (hypoxanthine-guanine phosphoribosyltransferase)
 2,385 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We studied 5 boys, 2 to 10 years old, with marked or complete deficiency of hypoxanthine-guanine phosphoribosyltransferase and Lesch-Nyhan syndrome with varying degrees of mental retardation, dysarthria, chorea, dystonia, spasticity, and ataxia. Four patients had marked reduction of homovanillic acid in the cerebrospinal fluid (CSF) and all showed low CSF 3-methoxy-4-hydroxy phenylethylene glycol, indicating reduced dopamine and norepinephrine turnover. Three patients showed high CSF 5-hydroxyindoleacetic acid, suggesting increased serotonin turnover. Some patients improved with carbidopa-levodopa, but others benefited from tetrabenazine, a monoamine-depleting agent. This study provides support for the theory of abnormal central monoamine metabolism in Lesch-Nyhan syndrome.
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PMID:Lesch-Nyhan syndrome: a study of motor behavior and cerebrospinal fluid neurotransmitters. 245 72

A variety of inheritable metabolic disorders produce movement disorders. A lists of conditions associated with tremor, athetosis, chorea, dystonia and myoclonus are presented as a guide for the differential diagnosis of such abnormal involuntary movements. The list includes aminoacidopathies, lipidoses, mucopolysaccharidoses, mucolipidoses, organic acidemias, mitochondrial cytopathies and disorders of carbohydrate, purine, and metal metabolism. Clinical, pathological and biochemical features of movement disorders of three typical examples, Wilson's disease, Lesch-Nyhan syndrome and glutaric acidemia type 1, are described.
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PMID:[Movement disorders in miscellaneous disorders--inherited metabolic diseases]. 827 72

Lesch-Nyhan syndrome is a rare, x-linked, recessive disorder of purine metabolism resulting in hyperuricemia, spasticity, choreoathetosis, dystonia, self-injurious behavior, and aggression, without significant cognitive impairment. Anesthetic management of inpatients who demonstrate classic manifestations of Lesch-Nyhan syndrome and require surgical interventions have been described. There are no guidelines in the literature addressing the anesthetic management of the outpatient with Lesch-Nyhan syndrome. Specifically, sudden, unexplained death, abnormalities in respiration, apnea, severe bradycardia, and an increased incidence of vomiting and chronic pulmonary aspiration may preclude this patient population from receiving anesthesia for outpatient procedures. General anesthesia with spontaneous ventilation was performed for diagnostic, radiographic imaging in 11 outpatients with Lesch-Nyhan syndrome using intravenous propofol. A bolus dose of 1.5 to 2.0 mg/kg propofol was followed by maintenance doses of 60 to 160 mcg/kg/min. Results during and following sedation indicated end-tidal carbon dioxide ranges between 34 mmHg and 59 mmHg. Respiratory rates were never below 10 breaths/min and no partial/complete airway obstruction or labored breathing was clinically evident. Hemodynamics were within 30% of presedation values. No patient demonstrated nausea, vomiting, or pulmonary aspiration. Baseline neuropsychologic status was achieved following sedation, and patients were discharged from the hospital 35 to 90 minutes after sedation was completed. Potential risks and benefits of using propofol in this patient population are discussed.
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PMID:Use of propofol anesthesia during outpatient radiographic imaging studies in patients with Lesch-Nyhan syndrome. 905 48

Lesch-Nyhan syndrome (LNS) is an X-linked hereditary disorder caused by a deficiency of hypoxanthine-guanine phosphoribosyltransferase. Patients with this syndrome are characterized by hyperuricemia, self-mutilation, developmental retardation, and movement disorders such as spasticity and dystonia. The authors performed bilateral chronic stimulation of the globus pallidus internus for control of dystonic movements in a 19-year-old man with LNS. His self-mutilating behavior unexpectedly disappeared after chronic stimulation. This is the first case of LNS that has been successfully treated with deep brain stimulation. The findings indicate that neurobehavioral features of this syndrome are either mediated in the basal ganglia pathways or secondary to the dystonia.
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PMID:Disappearance of self-mutilating behavior in a patient with lesch-nyhan syndrome after bilateral chronic stimulation of the globus pallidus internus. Case report. 1259 32

Lesch-Nyhan syndrome (LNS) is a rare X-recessive disorder that leads to virtually complete deficiency of the purine salvage enzyme hypoxanthine-guanine phosphoribosyltransferase (HPRT). Partial HPRT deficiency results in uric acid overproduction with subsequent hyperuricemia, nephrolithiasis, renal failure and gouty arthritis. In contrast, at complete HPRT deficiency, besides overproduction of uric acid neurological problems appear including spasticity, choreoathetosis, mental retardation, and compulsive self-mutilation. The cause for the uric acid overproduction has been clarified, but the connection between the enzyme deficiency and the neurological manifestations in LNS remains unclear. A hypothesis, which explains this relation, is proposed in the paper. The hypothesis has several important points most substantial of which is the accelerated biosynthesis of semiessential amino acid histidine that against the background of accelerated purine de novo biosynthesis results in 5-aminoimidazole-4-carboxamideribotide (AICAR) and histamine accumulation. The histamine and AICAR were determined to be the compounds that cause the neurobehavioral symptoms of LNS for several reasons. First, in the basal ganglia a balance between the direct (activating) and the indirect (inhibiting) pathways arising on the basis of the antagonistic and reciprocal dopamine-adenosine interactions normally exists. This balance can tonically regulate smooth voluntary movements and the activity of the thalamus, which, in turn, processes the afferent sensorimotor signals from the whole body to the all areas of the cerebral cortex and is concerned to modulate mental development and bring sensory information into awareness. Second, histamine is known to induce a selective damage in dopaminergic neurons inhibiting the direct dopaminergic pathway, which could lead to muscular rigidity, and slowness in initiating movements as well as tremor that are characteristic of Parkinsonism in LNS. Third, AICAribosid (AICAR breakdown product) is a potent adenosine A2a receptor antagonist inhibiting the indirect dopamine-adenosinergic pathway and, therefore, could be responsible for the choreoathetosis, dystonia and ballismus found in LNS. The excitatory-inhibitory disbalance in the basal ganglia could result in inadequate modification of the thalamus activity with subsequent mental retardation and symptoms that include the patients not being aware for their own bodies that could give rise to self-mutilation. Finally, a possibility for the creation of a new animal model that could exactly match the human LNS is proposed in the paper.
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PMID:The biochemical basis of the neurobehavioral abnormalities in the Lesch-Nyhan syndrome: a hypothesis. 1519 65

Lesch-Nyhan syndrome (LNS) is an X-linked recessive disorder resulting from a deficiency of the metabolic enzyme hypozanthine-guanine phosphoribosyltransferase (HPRT). This syndrome presents with abnormal metabolic and neurological manifestations including hyperuricemia, mental retardation*, spastic cerebral palsy (CP), dystonia, and self-mutilation. The mechanism behind the severe self-mutilating behavior exhibited by patients with LNS is unknown and remains one of the greatest obstacles in providing care to these patients. This report describes a 10-year-old male child with confirmed LNS who was treated for self-mutilation of his hands, tongue, and lips with repeated botulinum toxin A (BTX-A) injections into the bilateral masseters. Our findings suggest that treatment with BTX-A affects both the central and peripheral nervous systems, resulting in reduced self-abusive behavior in this patient.
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PMID:Botulinum toxin as a novel treatment for self-mutilation in Lesch-Nyhan syndrome. 1613 73

Lesch-Nyhan disease (LND) is caused by deficiency of the purine salvage enzyme hypoxanthine-guanine phosphoribosyltransferase (HPRT). Affected individuals exhibit over-production of uric acid, along with a characteristic neurobehavioural syndrome that includes mental retardation, recurrent self-injurious behaviour and motor disability. Prior studies involving relatively small numbers of patients have provided different conclusions on the nature of the motor disorder. The current study includes the results of a multi-centre international prospective study of the motor disorder in the largest cohort of patients studied to date. A total of 44 patients ranging from 2 to 38 years presented a characteristic motor syndrome that involved severe action dystonia superimposed on baseline hypotonia. Although some patients also displayed other extrapyramidal or pyramidal signs, these were always less prominent than dystonia. These results are compared with a comprehensive review of 122 prior reports that included a total of 254 patients. Explanations for the differing observations available in the literature are provided, along with a summary of how the motor disorder of LND relates to current understanding of its pathophysiology involving the basal ganglia.
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PMID:Delineation of the motor disorder of Lesch-Nyhan disease. 1654 99

We describe intermittent or sustained severe involuntary tongue protrusion in patients with a dystonic syndrome. Speech, swallowing, and breathing difficulties can be severe enough to be life threatening. Causes include neuroacanthocytosis, pantothenate kinase-associated neurodegeneration, Lesch-Nyhan syndrome, and postanoxic and tardive dystonia. The pathophysiology of intermittent severe tongue protrusion remains unknown. Tongue protrusion dystonia is often unresponsive to oral drugs but may benefit from botulinum toxin injections into the genioglossus muscle. Bilateral deep brain pallidal stimulation was beneficial in two cases.
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PMID:Severe tongue protrusion dystonia: clinical syndromes and possible treatment. 1700 Sep 58

The Lesch-Nyhan syndrome is an X-linked recessive disorder caused by a deficiency in hypoxanthine-guanine phosphoribosyl transferase, a purine salvage enzyme. Affected individuals exhibit a characteristic neurobehavioral disorder with delayed acquisition of motor skills, dystonia, severe self-mutilations, and aggressive behavior. Deep brain stimulation has been previously proposed for controlling isolated involuntary movements and psychiatric disorders. We applied a double bilateral simultaneous stimulation to limbic and motor internal pallidum in one patient for controlling both behavioral and movement disorders, respectively. The injurious compulsions disappeared; dystonia and dyskinesia were decreased at 28 months follow-up.
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PMID:Antero-ventral internal pallidum stimulation improves behavioral disorders in Lesch-Nyhan disease. 1785 83

Deficiency of hypoxanthine-guanine phosphoribosyltransferase (HPRT) activity is an inborn error of purine metabolism associated with uric acid overproduction and a continuum spectrum of neurological manifestations depending on the degree of the enzymatic deficiency. The prevalence is estimated at 1/380,000 live births in Canada, and 1/235,000 live births in Spain. Uric acid overproduction is present inall HPRT-deficient patients and is associated with lithiasis and gout. Neurological manifestations include severe action dystonia, choreoathetosis, ballismus, cognitive and attention deficit, and self-injurious behaviour. The most severe forms are known as Lesch-Nyhan syndrome (patients are normal at birth and diagnosis can be accomplished when psychomotor delay becomes apparent). Partial HPRT-deficient patients present these symptoms with a different intensity, and in the least severe forms symptoms may be unapparent. Megaloblastic anaemia is also associated with the disease. Inheritance of HPRT deficiency is X-linked recessive, thus males are generally affected and heterozygous female are carriers (usually asymptomatic). Human HPRT is encoded by a single structural gene on the long arm of the X chromosome at Xq26. To date, more than 300 disease-associated mutations in the HPRT1 gene have been identified. The diagnosis is based on clinical and biochemical findings (hyperuricemia and hyperuricosuria associated with psychomotor delay), and enzymatic (HPRT activity determination in haemolysate, intact erythrocytes or fibroblasts) and molecular tests. Molecular diagnosis allows faster and more accurate carrier and prenatal diagnosis. Prenatal diagnosis can be performed with amniotic cells obtained by amniocentesis at about 15-18 weeks' gestation, or chorionic villus cells obtained at about 10-12 weeks' gestation. Uric acid overproduction can be managed by allopurinol treatment. Doses must be carefully adjusted to avoid xanthine lithiasis. The lack of precise understanding of the neurological dysfunction has precluded development of useful therapies. Spasticity, when present, and dystonia can be managed with benzodiazepines and gamma-aminobutyric acid inhibitors such as baclofen. Physical rehabilitation, including management of dysarthria and dysphagia, special devices to enable hand control, appropriate walking aids, and a programme of posture management to prevent deformities are recommended. Self-injurious behaviour must be managed by a combination of physical restraints, behavioural and pharmaceutical treatments.
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PMID:Hypoxanthine-guanine phosophoribosyltransferase (HPRT) deficiency: Lesch-Nyhan syndrome. 1806 74


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