Classic PMD; Pelizaeus-Merzbacher Brain Sclerosis; Adult Pelizaeus-Merzbacher Disease; Classic Pelizaeus-Merzbacher Disease

Pelizaeus-Merzbacher Disease (PMD) is a rare, neurodegenerative disorder, and is one of a group of genetic disorders called leukodystrophies affecting the white matter of the brain and spinal cord. There are two main types of PMD: Classic PMD and Connatal PMD. Pelizaeus-Merzbacher Disease-Classic Form (Classic PMD) is the most common type.

Diagnostic testing: MRI demonstrates symmetric and widespread abnormality of the white matter of the cerebrum, brain stem, and cerebellum.

Physical findings: Individuals with Classic PMD may have:

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  Infantile nystagmus (repetitive, uncontrolled eye movements);

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  Abnormal muscle tone and spasticity;

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  Stridor (high-pitched, whistling sound heard while taking in a breath);

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  Poor coordination;

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  Delayed motor development;

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  Epileptic seizures;

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  Ataxia (loss of full control of bodily movements);

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  Intellectual disability; and

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  Choreoathetosis (involuntary movements in a combination of chorea (irregular migrating contractions) and athetosis (twisting and writhing).

ICD-9: 330.0

Classic PMD progresses slowly and children generally survive to adulthood. Some children die before the age of 20, while others live much longer.

There is no cure for PMD, and treatment is supportive. Tracheostomy and/or feeding tubes may be necessary to avoid aspiration. Physical therapy, orthotics, and antispasticity medications may aid in motor development, and minimize joint contractures and kyphoscoliosis; orthopedic surgery is sometimes indicated. Developmental therapy and special education help to maximize cognitive achievement, and speech/language therapy aids in language development.

SUGGESTED PROGRAMMATIC ASSESSMENT*

Suggested MER for Evaluation:

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  Clinical history and examination that describes the diagnostic features of the impairment;

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  MRI of the brain showing abnormal white matter (demyelination);

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  Progress reports of physical therapy, speech/language therapy; and

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  Reports of educational evaluations/academic progress.

Suggested Listings for Evaluation:

REMARKS