Definition of Neuronal ceroid lipofuscinoses (NCLS):

Neuronal ceroid lipofuscinoses (NCLS) refers to a group of rare, inherited disorders of the nerve cells.

There are three main types of NCLS:

• Adult (Kufs' or Parry's disease)
• Juvenile (Batten disease)
• Late infantile (Jansky-Bielschowsky)

Causes, incidence, and risk factors:

NCLS is a type of neurodegenerative disorder. It involves the buildup of an abnormal material called lipofuscin in the brain. Evidence suggests that NCLS is caused by problems with the brain's ability to remove and recycle proteins.

Lipofuscinoses are inherited as autosomal recessive traits. That means if both parents carry the trait, each child has:

• A 1 in 4 chance of having the disease
• A 2 in 4 chance of not having the disease but carrying the trait
• A 1 in 4 chance of not having the disease and not being a carrier

Symptoms:

• Abnormally increased muscle tone or spasm (myoclonus)
• Blindness or vision problems
• Dementia
• Lack of muscle coordination
• Mental retardation with decreasing mental function
• Movement disorder (choreoathetosis)
• Seizures
• Unsteady gait (ataxia)

Signs and tests:

The disorder may be seen at birth, but it is usually diagnosed much later.

Tests include:

• Autofluorescence (a light technique)
• EEG
• Electron microscopy of a skin biopsy
• Electroretinogram
• Genetic testing
• MRI or CT scans of the brain
• Tissue biopsy

Treatment:

Treatment depends on the type and extent of symptoms. You may need lifelong assistance and care.

Support Groups:

For information and support, see www.bdsra.org.

Expectations (prognosis):

The younger the person is when the disease appears, the greater the risk for disability and early death. Those who develop the disease early can have vision problems that progress to blindness, and problems with mental function that get worse. If the disease emerges in the first year of life, death by age 10 is likely.

If the disease occurs in adulthood, symptoms will be milder with no vision loss and a normal life expectancy.

Complications:

• Vision impairment or blindness (with the early-onset forms of the disease)
• Mental impairment, ranging from severe retardation at birth to dementia later in life
• Rigid muscles (due to severe problems with the nerves that control muscle tone)

The person may become totally dependent on others for help with daily activities.

Calling your health care provider:

Call your health care provider if your child shows symptoms of blindness or retardation.

Prevention:

Genetic counseling is recommended if your family has a known history of NCLS. Prenatal or preimplantation genetic testing may be available depending on the specific type of disease.