metachromatic leukodystrophy

(redirected from Greenfield syndrome)
Also found in: Encyclopedia.

leukodystrophy

 [loo″ko-dis´tro-fe]
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 leukodystrophy

metachromatic leukodystrophy

An 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.

Clinical findings
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.

Molecular pathology
Defects in ARSA on chromosome 22q13.31-qter, which encodes arylsulfatase A, causes metachromatic leukodystrophy.

Treatment
All therapies are experimental; none are effective.

Prognosis
Universally fatal.

metachromatic leukodystrophy

Neurology 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.

leukodystrophy

disorders or metabolic defects in the system required for the maintenance and degradation of normally formed myelin in newborn and young animals. Clinical signs begin some time after birth. See also leukoencephalopathy.

Afghan leukodystrophy
see hereditary myelopathy of Afghan hounds.
cavitating leukodystrophy
a familial, probably inherited, disease of Dalmatian dogs in which there is blindness and progressive motor dysfunction from a few months of age.
fibrinoid leukodystrophy
a familial disease of astrocytes causing ataxia, paresis and behavioral changes from an early age; reported in Labrador retrievers. Similar to Alexander's disease in humans.
globoid cell leukodystrophy
an inherited lysosomal storage disease of polled Dorset sheep, cats, and dogs, particularly Cairn terriers and West Highland white terriers, caused by a deficiency of the enzyme beta-galactocerebrosidase. From a young age, there is weakness that progresses to paralysis. Called also galactocerebrosidosis and Krabbe's disease.
metachromatic leukodystrophy
a leukoencephalopathy reported in cats, caused by a deficiency of the enzyme arylsulfatase A. There is accumulation of a sphingolipid (sulfatide) in tissues, with diffuse loss of myelin in the central nervous system and progressive neurological dysfunction.

metachromatic

having the characteristics of metachromasia.

metachromatic leukodystrophy
see metachromatic leukodystrophy.