A group of more than 50 rare and inherited neurological disorders that negatively affect the myelin (the protective covering of nerve cells in the brain and spine) is called leukodystrophy. It causes a progressive loss of neurological functions in infants, children, and adults (sometimes). Mostly, this condition is fatal.
People usually experience different symptoms because they depend on several factors. These include the type and severity of the condition, age, sex, and overall health. However, they often include problems with speaking, walking, vision, hearing, thinking, and other neurological functions. Some people with leukodystrophy may not have any symptoms.
Generally, this disorder occurs rarely in the U.S. and Canada. It affects about 1 in 6,000 to 1 in 100,000 live births. However, it often affects 3 in 100,000 live births in certain Asian countries.
Types of Leukodystrophy
Healthcare providers have found more than 50 types of this condition. Nowadays, they are still discovering new forms because each type is caused by a different genetic mutation. Check some types of leukodystrophy below:
- Adenoleukodystrophy (ALD) – This type of leukodystrophy negatively affects both the white matter (myelin sheath) in the brain and spinal cord. In some cases, it may also affect the adrenal glands that produce essential hormones. Mostly, the symptoms begin in childhood or early adulthood and may include problems with learning, hearing, and vision. Some people may also experience extreme tiredness (fatigue), lack of coordination, and difficulties with weight loss.
- Adult-onset autosomal-dominant leukodystrophy (ADLD) – This type of leukodystrophy often appears between the ages of 40 and 50. It negatively affects the muscles, movement, and cognition (thinking and remembering). Some people with ADLD may also experience problems with blood pressure and heart rate.
- Alexander disease – Most of the time, this condition causes developmental delays, seizures, and walking problems. While it develops in newborns and children, some types of Alexander disease may cause symptoms during adulthood.
- Canavan disease – This type of leukodystrophy often causes symptoms in early infancy, but some types of this disease may cause symptoms later in life. They often include developmental delays, weakness, swallowing problems, seizures, vision problems, and others.
- Cerebrotendinous xanthomatosis (CTX) – This condition negatively affects the white matter tendons and heart. It often causes the following symptoms, including abnormal movements, seizures, hallucinations, and changes in thinking.
- Childhood ataxia with central nervous system hypomyelination (CACH) – This condition is also known as vanishing white matter (VWM) because it destroys the white matter in the spinal cord and brain. Usually, people with CACH experience vision loss due to optic atrophy and speech loss within the first 5 years of life. Sometimes, it may also cause seizures, waking problems, loss of balance, and spasticity.
- Krabbe disease – This type of leukodystrophy is also known as globoid cell leukodystrophy, and it often causes symptoms in infancy. For example, weakness, irritability, feeding problems, developmental delays, neuropathy, and seizures. In rare cases, the symptoms of Krabbe disease may appear later in life.
- Metachromatic leukodystrophy – This condition may occur in babies, children, or adults and cause the following symptoms. Examples include changes in thinking and behavior, vision or hearing problems, seizures, neuropathy, and dementia.
- Pelizaeus-Merzbacher disease (PMD) – This form of leukodystrophy causes abnormal eye movements, spasticity, and developmental delays. Typically, PMD is a progressive disorder that often affects males.
- Refsum disease – This condition may appear at any age and cause blindness (loss of vision), walking problems, and numbness or tingling in the hands and feet. Some people may also experience dry skin, abnormal heart rhythm, and problems with the liver, kidneys, or bones.
What Are The Symptoms of Leukodystrophy?
Usually, people who suffer from this condition experience different symptoms because they depend on several factors. Examples include the type and severity of the condition, age, existing health problems, and sex. Check some general symptoms of leukodystrophy below:
- Problems with movement and coordination
- Difficulty eating and swallowing
- Slurred or slow speech
- Vision changes (including blindness)
- Hearing issues
- Loss of balance and strength
- Problems with mental processes (including memory, learning, attention, thinking, and others)
If you or your child has any of the previous symptoms, immediately contact your healthcare professional. Early detection and prompt treatment may help reduce the risk of serious complications.
Causes
This neurological disorder happens due to a mutation (change) in specific genes that control the growth and function of myelin. It is also known as white matter, and it protects the nerves in the brain and spine. When this protection is missing, the nerve cells are not able to function properly.
Abnormal genes that cause leukodystrophy can be passed from biological parents to their biological children or happen randomly as cells grow and divide. Sometimes, people have these abnormal genes but do not develop the disease. In such cases, the affected person is a carrier who may pass this abnormal gene to his/her children in the future.
Diagnosis
Physicians often start the diagnosis of leukodystrophy with a physical examination and questions about your symptoms and family history. However, they may also perform a neurological examination to get more clues about your condition. Usually, it is difficult to diagnose leukodystrophy because the symptoms it causes are very similar to those of other health conditions. Check below some tests often used to confirm or rule out this disease:
- Newborn screening examinations
- Blood and saliva tests to check for the abnormal genes often found in people with leukodystrophy
- Imaging tests – The following tests are used to get detailed images of the brain and spinal cord. Doctors often perform CT (computed tomography) scans and MRI (magnetic resonance imaging) scans.
Typically, most leukodystrophies go undiagnosed.
Treatment
There is no way to cure this condition. That’s why the goal of the treatment is to ease the symptoms, prevent life-threatening complications, and preserve some neurological function. Doctors often recommend the following treatments. These include:
- Hormone therapy (if you have adrenal gland dysfunction)
- Nutritional therapy or feeding tubes (to help children with swallowing and eating problems)
- Medicines to prevent or treat seizures, muscle tightness, and movement issues
- Speech, occupational, and physical therapy – These therapies are used to improve balance, speaking, mobility, and other skills.
- Gene therapy – This treatment is available for some types of leukodystrophy. It involves delivering changed genetic material to the cells, which changes how your cells produce some types of protein.
- A stem cell or bone marrow transplant – Doctors rarely prescribe this treatment because it is not suitable for all types of leukodystrophy. Usually, it is helpful in people with an early diagnosis of CTX.
Frequently Asked Questions
What is the life expectancy of someone with leukodystrophy?
Generally, the life expectancy of people who suffer from this disorder varies because it depends on the type and severity of the disease, age, sex, and overall health. For instance, some people with mild forms of leukodystrophy may have a normal lifespan, but others who develop a more severe type of this disorder may have a shortened life expectancy. For more details, discuss it with your doctor.
What is the cause of leukodystrophy?
Typically, leukodystrophies occur due to genetic mutations in specific genes that negatively affect the growth or maintenance of the myelin (the protective layer of nerves).
Can you recover from leukodystrophy?
Unfortunately, there is no way to cure this disorder. However, there are some new treatments that may help treat or stop the progression of some types of leukodystrophy if they are caught early.
Can leukodystrophy be detected before symptoms appear?
Yes. Some types of leukodystrophy can be detected before symptoms develop through newborn screening, genetic testing, or family screening if there is a known inherited mutation. Early diagnosis is important because certain treatments, such as gene therapy or stem cell transplantation, are more effective before significant nerve damage occurs.
Is leukodystrophy contagious?
No. Leukodystrophy is not contagious and cannot spread from one person to another through physical contact, respiratory droplets, or bodily fluids. It is an inherited or, less commonly, a spontaneously occurring genetic disorder.
Can adults develop leukodystrophy?
Although many leukodystrophies begin during infancy or childhood, some forms first appear in adulthood. Adult-onset leukodystrophies may cause problems with walking, balance, memory, behavior, muscle stiffness, or bladder function. Because the symptoms often resemble those of other neurological disorders, diagnosis may be delayed.
How is genetic testing helpful for families affected by leukodystrophy?
Genetic testing can identify the specific gene mutation responsible for the disorder. This information helps confirm the diagnosis, determine the inheritance pattern, guide treatment decisions, and allow family members to receive genetic counseling if they are planning to have children.
What complications can leukodystrophy cause?
As the disease progresses, leukodystrophy can lead to severe mobility problems, difficulty swallowing, recurrent lung infections caused by aspiration, seizures, vision and hearing loss, muscle stiffness, and cognitive decline. The risk and severity of complications vary depending on the specific type of leukodystrophy.
Can physical and occupational therapy help people with leukodystrophy?
Yes. While these therapies cannot cure leukodystrophy, they can help maintain strength, flexibility, balance, and independence for as long as possible. Physical, occupational, and speech therapy may also improve communication, daily functioning, and overall quality of life.
Should people with a family history of leukodystrophy seek genetic counseling?
Yes. Individuals with a family history of leukodystrophy should consider genetic counseling, especially before starting a family. A genetic counselor can explain the risk of passing the condition to future children, discuss available genetic tests, and help families make informed reproductive and healthcare decisions. Ask your healthcare provider if you have any other questions.
