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Metachromatic leukodystrophy

Disease definition

A rare lysosomal disease characterized by accumulation of sulfatides in the central and peripheral nervous system due to deficiency of the enzyme arylsulfatase A, leading to demyelination. Three clinical subtypes can be distinguished based on the age of onset: late infantile, juvenile, and adult. Lead symptoms are deterioration in motor or cognitive function or behavioral problems, depending on the subtype, all eventually culminating in a decerebrated state and death after a highly variable disease course and duration. Mode of inheritance is autosomal recessive.


Classification level: Disorder
  • Synonym(s):
    • Arylsulfatase A deficiency
    • MLD
  • Prevalence: 1-9 / 1 000 000
  • Inheritance: Autosomal recessive 
  • Age of onset: Childhood, Adolescent, Adult, Infancy
  • ICD-10: E75.2
  • ICD-11: 5C56.02
  • OMIM: 156310  249900  250100
  • UMLS: C0023522
  • MeSH: D007966
  • GARD: 3230
  • MedDRA: 10067609

Detailed information

General public


Disease review articles

Clinical Outcome Assessment (COA)

  • Patient-Centered Outcome Measures (PCOMs)
  • English (2023) - PROQOLIDTM
ERN produced/endorsed by ERN(s)   FSMR produced/endorsed by FSMR(s)
The documents contained in this web site are presented for information purposes only. The material is in no way intended to replace professional medical care by a qualified specialist and should not be used as a basis for diagnosis or treatment.