Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0026827 (hypotonia)
 5,860 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Several childhood multisystem disorders with prominent ophthalmological manifestations have been ascribed to the malfunction of the peroxisome, a subcellular organelle. The peroxisomal disorders have been divided into three groups: 1) those that result from defective biogenesis of the peroxisome (Zellweger syndrome, neonatal adrenoleukodystrophy, and infantile Refsum's disease); 2) those that result from multiple enzyme deficiencies (rhizomelic chondrodysplasia punctata); and 3) those that result from a single enzyme deficiency (X-linked adrenoleukodystrophy, primary hyperoxaluria type 1). Zellweger syndrome, the most lethal of the three peroxisomal biogenesis disorders, causes infantile hypotonia, seizures, and death within the first year. Ophthalmic manifestations include corneal opacification, cataract, glaucoma, pigmentary retinopathy and optic atrophy. Neonatal adrenoleukodystrophy and infantile Refsum's disease appear to be genetically distinct, but clinically, biochemically, and pathologically similar to Zellweger syndrome, although milder. Rhizomelic chondrodysplasia punctata, a peroxisomal disorder which results from at least two peroxisomal enzyme deficiencies, presents at birth with skeletal abnormalities and patients rarely survive past one year of age. The most prominent ocular manifestation consists of bilateral cataracts. X-linked (childhood) adrenoleukodystrophy, results from a deficiency of a single peroxisomal enzyme, presents in the latter part of the first decade with behavioral, cognitive and visual deterioration. The vision loss results from demyelination of the entire visual pathway, but the outer retina is spared. Primary hyperoxaluria type 1 manifests parafoveal subretinal pigment proliferation. Classical Refsum's disease may also be a peroxisomal disorder, but definitive evidence is lacking. Early identification of these disorders, which may depend on recognizing the ophthalmological findings, is critical for prenatal diagnosis, treatment, and genetic counselling.
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PMID:The peroxisome and the eye. 171 72

Peroxisomal disorders are divided into two groups from a clinical point of view. Diseases in the first group, peroxisome-deficient disorders (PDD), Zellweger-like syndrome, and isolated deficiencies of peroxisomal beta-oxidation enzymes, are characterized by common clinical features including psychomotor retardation, hypotonia, hepatic dysfunction and visual disturbance. The second group includes diseases with a unique manifestation, such as X-linked adrenoleukodystrophy, hyperoxaluria type I and rhizomelic chondrodysplasia punctata. We investigated clinical aspects and the genetic basis of PDD, and the significance of peroxisomes in the development of human brain. Neuroradiological and neurophysiological studies revealed that thick cortex, colpocephaly and multifocal spikes were characteristic findings of PDD patients in the early infantile period. Cytogenetic studies elucidated the presence of eleven complementation groups among PDD, indicating the presence of eleven pathogenic genes for PDD. Molecular studies elucidated two of these genes, PAF-1 and PXR-1. Immunohistochemical studies clarified that the catalase-positive neurons appeared in the basal ganglia, thalamus, and cerebellum at 28 weeks of gestation, and in the cortex at 35 weeks. Immunopositive glial cells appeared from the deep to superficial white matter with increasing gestational age. These results suggest the important role of peroxisomes in neuronal maturation and myelinogenesis.
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PMID:Peroxisomal disorders: clinical aspects. 899 63

The disorders of peroxisomal beta-oxidation, which have been well characterised at the molecular level, include defects of acyl-CoA oxidase, defects of the D-bifunctional protein (D-BP) (including specific defects of its enoyl-CoA hydratase and D-3-hydroxyacyl-CoA dehydrogenase components), defects of the very-long-chain fatty acid (VLCFA)-CoA importer [X-linked adrenoleukodystrophy (ALD)] and alpha-methylacyl-CoA racemase deficiency. A survey of the clinical consequences of these defects indicates that defects in the acyl-CoA oxidase and D-BP can produce neonatal hypotonia, seizures in early infancy, retinopathy and progressive neurological dysfunction with leukodystrophy on imaging. Defects in the VLCFA-CoA importer and in the racemase do not produce disease until a long time after the neonatal period. However, again the clinical picture is dominated by neurological disease: impaired cognitive function with leukodystrophy in childhood X-linked ALD and retinopathy and neuropathy in racemase deficiency. It is difficult to escape the conclusion that defective peroxisomal beta-oxidation has effects (such as impaired neuronal migration in the developing brain), which are more serious than those produced by the accumulation of substrates (VLCFAs, pristanic acid) alone.
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PMID:Clinical consequences of defects in peroxisomal beta-oxidation. 1135 71

We report a 4-year-old girl heterozygous for X-linked adrenoleukodystrophy (ALD) who displayed dopa-responsive motor symptoms and was subsequently diagnosed with sepiapterin reductase deficiency (SPR; OMIM 182125). Her father and paternal uncle had known ALD, and she was found to have elevated plasma very long chain fatty acids and a mutation in the ABCD1 gene. She had language delay, severe hypotonia and abnormal eye movements and responded dramatically to a trial of levodopa (4 mg/kg per day). Two mutations within the gene for sepiapterin reductase were found and cultured skin fibroblasts demonstrated near zero activity of the enzyme. This case illustrates the importance of treatment trials that may give rise to biochemical clues to the underlying diagnosis, and the need to continue to search for diagnoses despite a misleading family history.
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PMID:Levodopa response reveals sepiapterin reductase deficiency in a female heterozygote with adrenoleukodystrophy. 2343 Aug 77

We present a 9-year-old boy with X-linked cerebral adrenoleukodystrophy (X-linked ALD) and previous umbilical cord transplant who required general anaesthesia. An anaesthetic plan for each individual should be tailored to ensure the best possible anaesthetic care for these patients. The anaesthetic considerations include mental retardation, seizure disorder, hypotonia, liver function abnormalities, gastro-oesophageal reflux, impaired adrenocortical function and immunosuppression. Pre-operative sedation should be avoided because of hypotonia of the pharyngeal muscles. Anti-convulsants are continued, and potentially epileptogenic anaesthetic agents are avoided. The patient was intubated using a modified rapid sequence induction with a head up position of 30 degrees. Four other cases have been reported in literature. Nevertheless, there is still no established anaesthetic management for these patients, and total intravenous anaesthesia can be considered as a safe and alternative method of anaesthesia. To the best of our knowledge, this is the first reported use of total intravenous anaesthesia with propofol and remifentanil in a case of cerebral adrenoleukodystrophy, and with a favourable outcome.
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PMID:Anaesthesia for a child with adrenoleukodystrophy: A case report and review of the literature. 2470 Sep 3

We report a 9-year-old boy, with childhood cerebral X-linked adrenoleukodystrophy (CCALD), presenting with an episode of loss of consciousness, fixed gaze, hypotonia and vomit with spontaneous resolution and post-ictal sleep. Behavioural impairment has been observed since the previous five months. Magnetic Resonance Images (MRI) revealed isolated bilateral, symmetric, confluent temporal white matter lesions involving also corticospinal tracts, with sparing of the parieto-occipital and frontal white matter. This report outlines an atypical neuroradiological localization of X-linked adrenoleukodystrophy and neuropsychological findings not specifically related to the brain involvement seen at the MRI.
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PMID:A novel temporal pattern of childhood cerebral X-linked adrenoleukodystrophy. 2913 75

X-linked adrenoleukodystrophy (X-ALD) belongs to a family of rare diseases due to inborn errors of metabolism. It has a wide spectrum of clinical manifestations that anaesthesiologists should recognise during the perioperative period (respiratory centre dysfunction, hypotonia, adrenal or hepatic failure, gastroesophageal reflux disease, osteopenia, seizures).The case is presented of a 42-year-old X-linked adrenoleukodystrophy female carrier, who underwent combined general and an ultrasound-guided interscalene brachial plexus block anaesthesia for shoulder arthroscopy. Induction was performed with thiopentone and fentanyl, and sevoflurane was used as inhaled maintenance agent. No events were recorded during the procedure. Her post-operative recovery was satisfactory and she was later discharged home.
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PMID:Perioperative management of a female diagnosed with heterozygous X-linked adrenoleukodystrophy scheduled for shoulder arthroscopy. 3044 97