Adrenoleukodystrophy (ALD) is a progressive, genetic disease that affects the adrenal glands, the spinal cord, and the white matter (myelin) of the nervous system. ALD is considered a rare disease and affects approximately 1 in 17,000 people worldwide.
ALD is caused by the mutation of a single gene named ABCD1. This gene makes a protein that helps break down very long chain fatty acids (VLCFAs) that are naturally present in the human body and also introduced through diet. This chemical breaking-down process provides the body with energy. Because this particular gene is defective and does not correctly make the required protein in individuals with ALD, above-average levels of these fatty acids build up in patients’ blood and organ tissue. (source: https://aldconnect.org)
Cerebral ALD affects 35% of boys with ALD and 20% of men with ALD. Characterized by brain inflammation, cerebral ALD can only be diagnosed through an MRI.
Inflammation spreads throughout the brain. The longer the inflammation spreads unchecked, the more severe the symptoms.
Symptoms may initially include: inattention, deterioration in handwriting skills, and decreased school/work performance; difficulty in understanding speech; difficulty in reading and understanding written material; clumsiness; visual disturbances and occasionally double vision; and unpredictable aggressiveness or unexplained inappropriate behavior. In some boys, seizures may be the first symptom. Symptom severity varies from patient to patient.
Gradually, as the disease spreads throughout the brain, its symptoms grow even worse, including blindness, deafness, seizures, loss of muscle control, and progressive dementia. This relentless downward spiral leads to a vegetative state or death, usually within 2-5 years of diagnosis.
Adrenomyeloneuropathy (“AMN”) is characterized by inflammation of the spinal cord. Men can develop this in their early 20s through adulthood. It is estimated that 80% of men with ALD will develop some symptoms of AMN in their life.
Symptoms may include: a burning sensation in the feet, restless legs, loss of balance, sexual dysfunction, incontinence, progressive stiffness and weakness of the limbs, and inability to control muscle movement.
Adrenal Insufficiency affects approximately and is a result of permanent injury to the adrenal glands from elevated very-long-chain fatty acid levels. Although it is treatable with steroid replacement medications, adrenal insufficiency can be life-threatening if it is not recognized quickly.
WOMEN WITH ALD
Women with ALD were previously thought to be “only carriers” of the disease, but now it is known that women can experience symptoms ranging from mild to severe. Symptoms vary in women, but many times include bowel and bladder dysfunction, pain in the extremities, and walking difficulties. Cerebral disease and adrenal insufficiency are rare in women with ALD.
For more information about ALD phenotypes or physical manifestations, please visit https://aldconnect.org.