About 1 in 17,000 people are born with a genetic disease called adrenoleukodystrophy (ALD). This severe brain disorder is sometimes called Addison’s disease or cerebral sclerosis. It mainly affects boys and men. There’s no cure yet, but a diagnosis early in life may keep it from getting worse.
What Is It?
ALD causes severe damage to your nervous system. It does this by breaking apart the fatty covering (called myelin) that protects nerves in your brain and spinal cord. This makes it harder for nerves to send messages to your brain.
The adrenal glands, which help control things like your immune system, blood pressure, and other functions, are also harmed by ALD. Because of that, your body can’t make enough of the hormones you need to be healthy.
How Do You Get ALD?
A mutated gene on the X chromosome (the strand of DNA that decides if you’re born male or female) is the cause of ALD. Males have one X chromosome, so only need to inherit one damaged gene from a parent to be affected. Females have two X chromosomes so are less likely to have ALD. If they do, it’s often less severe.
What Are the Different Types?
ALD can come in several different forms. Symptoms will vary with each one, but often become worse over time.
Cerebral demyelinating ALD: 45% of people with ALD have this type. It’s the most severe form of ALD. Symptoms often start between ages four and eight and include:
- Attention deficit disorder (ADD)
- Problems with vision, hearing, and motor function
- Behavior problems
- Getting tired easily
- Low blood sugar
- Eye pain
- Viral infections that keep coming back
- Skin that looks tanned or bronzed
Adrenomyeloneuropathy (AMN): This adult form of ALD tends to have milder symptoms. About half of those who have it don’t show signs until they’re in their 20s or 30s. Still, like ALD, AMN can cause a severe loss of brain function. Some early signs are:
- Trouble walking
- Balance problems
- Changes in gait (how you walk)
- Numbness or tingling in the legs
- Arm weakness
- Feeling an urgent need to pee or poop
- Not being able to get or keep an erection
Addison’s disease: Over time, ALD causes severe damage to the adrenal glands. This can’t be reversed. The symptoms include:
- Low blood pressure
- Darkened skin
- Stomach pain
Female ALD: Women who inherit the mutated gene that causes ALD often don’t have the brain disease, but may show mild symptoms. Most of the time, these start after the age of 35. They can include:
- Joint pain
- Urinary problems
How Is ALD Diagnosed?
The illness may take a while to be diagnosed since other illnesses may need to be ruled out first. Many early symptoms can be missed or blamed on more common and milder health issues like attention deficit disorder (ADD) or learning disabilities.
If your doctor suspects ALD, they may order two tests. One is a blood test that looks for a special type of fatty acids that people with ALD have in high amounts. This test works best in men. It’s not as precise when used on women.
The other way to confirm ALD is through an MRI (magnetic resonance imaging). A brain scan can look for lesions (signs of damage) caused by the disease.
Based on your results, your doctor will assign you a “Loes score.” This measures the amount of brain damage seen on a scale from 0.5 (normal) to 34. Anything above 14 is a sign of severe ALD.
How Is ALD Treated?
The list of treatments for ALD is short:
Bone marrow transplant: Boys with early signs of ALD can benefit from this procedure. Healthy red blood cells from a donor can help prevent further myelin damage. The process can take months and recovery is long, but children who get a transplant early enough can have normal or near-normal lives.
Gene therapy: This new treatment takes out damaged stem cells, repairs the “faulty” gene that causes ALD, then puts a healthy version back in. It carries fewer risks than a bone marrow transplant, but more research needs to be done before it’s widely used.
Steroids: A daily pill can help manage Addison’s disease.
Physical therapy: If walking is a problem, a physical therapist can provide exercises to help strengthen your muscles and make it less painful.
Lorenzo’s oil: This mix of rapeseed and olive oils stops the body from making certain fatty acids that cause myelin to break down. Although it may slow the onset of ALD in boys, Lorenzo’s oil isn’t yet approved by the Food and Drug Administration. It’s also unclear whether it helps men with AMN.
What’s the Prognosis?
More research is being done on how to prevent and treat ALD, but the outlook for people who have it is still poor. Death often occurs within 1 to 10 years of first having symptoms.
The earlier ALD can be diagnosed, the better. Experts believe that all treatments work best when given before symptoms start or soon after.