metachromatic leukodystrophy(redirected from Leukodystrophy, metachromatic)
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disturbance of the white substance of the brain. See also adrenoleukodystrophy and leukoencephalopathy.
metachromatic leukodystrophy a hereditary leukoencephalopathy, marked by accumulation of a sphingolipid (sulfatide) in tissues, with diffuse loss of myelin in the central nervous system and progressive dementia and paralysis; classified according to age of onset as infantile, juvenile, and adult.
met·a·chro·mat·ic leu·ko·dys·tro·phy[MIM*250100, MIM*249900]
a metabolic disorder, with onset usually in the second year of life and death often before age 5 years, with loss of myelin and accumulation of metachromatic lipids (galactosyl sulfatidates) in the white matter of the central and peripheral nervous systems leading to motor symptoms, paralysis, convulsions, and progressive cerebral deterioration. Autosomal recessive inheritance caused by mutation in either the arylsulfatase A gene (ARSA) on 22q or the prosaposin gene (PSAP) on 10q. There is a dominant form occurring in adults [MIM*156310].
metachromatic leukodystrophyAn autosomal recessive lysosomal storage disease (OMIM:250100) caused by arylsulfatase A deficiency, characterised by an accumulation of sulphated sphingolipid (cerebroside-3-sulfate) in neural and non-neural tissues, and a diffuse loss of myelin in the CNS.
Onset by age two, death by age five, with upper and lower motor neuron disease, decreased nerve conduction, spasms, ataxia, oculomotor paralysis, bulbar palsy, blindness, deafness, and dementia.
Defects in ARSA on chromosome 22q13.31-qter, which encodes arylsulfatase A, causes metachromatic leukodystrophy.
All therapies are experimental; none are effective.
metachromatic leukodystrophyNeurology An AR lysosomal storage disease caused by arylsulfatase. A deficiency, characterized by sulfated sphingolipid accumulation, ↓ myelin Clinical forms Infantile form–most severe; adult form–least severe; juvenile form–intermediate Clinical Onset by age 2, death by age 5 with upper and lower motor neuron disease, ↓ nerve conduction, spasms, ataxia, oculomotor paralysis, bulbar palsy, blindness, deafness, dementia. See Arylsulfatase A, Leukodystrophy.
met·a·chro·mat·ic leu·ko·dys·tro·phy(MLD) (met'ă-krō-mat'ik lū'kō-dis'trŏ-fē)
A metabolic disorder, usually of infancy, characterized by myelin loss, accumulation of metachromatic lipids (galactosyl sulfatidates) in the white matter of the central and peripheral nervous systems, progressive paralysis, and mental retardation; psychosis and dementia are seen in adults.