Definition of Metachromatic leukodystrophy
In metachromatic leukodystrophy, a rare hereditary (genetic) disorder, deficiency of an enzyme that helps break down fatty substances (lipids) causes lipids to build up in your brain, spinal cord and peripheral nerves. As a result, your brain and nervous system progressively lose function.
Rarely, a deficient nonenzyme protein (activator protein) causes metachromatic leukodystrophy.
You or your child may have one of three types of metachromatic leukodystrophy. Each type occurs at different ages and has different signs and symptoms.
The types, which may overlap, include:
- Infantile form, occurring between ages 6 months and 2 years
- Juvenile form, occurring between ages 3 and 6 (early juvenile) or between ages 6 and 16 (late juvenile)
- Adult form, occurring at age 17 or older