Primary lateral sclerosis (PLS)

2021-08-26 09:25 PM

Lateral sclerosis can occur at any age but is more common after age 40. A subtype of lateral sclerosis, called juvenile lateral sclerosis, begins in childhood and is caused by genes abnormalities passed from parents to children.


Primary lateral sclerosis (PLS), short called lateral sclerosis, causes voluntary muscle weakness, such as controlling the use of the legs, arms, and tongue. Lateral sclerosis is a type of motor neuron disease that causes neuromuscular cells to die, causing weakness.

Lateral sclerosis can occur at any age but is more common after age 40. A subtype of lateral sclerosis, called juvenile lateral sclerosis, begins in childhood and is caused by genes. abnormalities passed from parents to children.

Lateral sclerosis is often confused with one another, more commonly sclerosis of the nerve cells called amyotrophic lateral sclerosis (ALS). However, amyotrophic lateral sclerosis progresses more slowly than atrophy, and in many cases is not considered fatal.


Signs and symptoms of lateral sclerosis often take years to progress. These include:

Weak leg stiffness and spasticity in the legs.

Stumbling, difficulty with balance, and clumsiness such as weakened leg muscles.

Weakness and stiffness progress to the trunk, then the arms, hands, tongue, and jaw.

Hoarseness, decreased speech, slurred speech, and drooling like facial weakness.

Difficulty with swallowing and breathing in the late stages of the disease.

Less commonly, lateral sclerosis begins in the tongue or hands and then progresses down the spinal cord to the legs.

Make an appointment with your doctor if you have persistent problems with stiffness or weakness in your legs, or with swallowing or speaking.

If you develop involuntary muscle spasms or seem out of balance more often than usual, make an appointment with your doctor for an evaluation.


Lateral sclerosis in adults

The cause of lateral sclerosis in adults is unknown. In most cases, it is not an inherited disease, and it is not known why or how it started.

Juvenile lateral sclerosis

Juvenile lateral sclerosis may have an identifiable cause: A mutation in a gene called ALS2. Although researchers don't fully understand how it causes diseases, they do know that the ALS2 gene, which is responsible for providing instructions for execution, called the protein alsin, is abundant in nerve cells. motor. When the instructions change in someone, it causes juvenile lateral sclerosis, the protein alsin becomes unstable and does not work properly, thereby impairing normal muscle function. Adults with amyotrophic lateral sclerosis do not have the mutated gene.

Juvenile lateral sclerosis is an autosomal recessive genetic disease, which means that both parents must carry the gene to pass it on to their children.


Although the average progression of lateral sclerosis lasts about 20 years, the disease is highly variable from person to person. Some people can continue to walk, but others will eventually need a wheelchair or other assistive device for mobility or other activity.

Adult amyotrophic lateral sclerosis is not considered to shorten life expectancy, but it can gradually affect the quality of life as muscles become weaker. Weaker muscles are more likely to fall, which can lead to injury.

Tests and diagnostics

There is no single test that confirms the diagnosis of lateral sclerosis. In fact, because the disease can mimic the signs and symptoms of other neurological diseases such as multiple sclerosis and muscular dystrophy, some tests are done to rule out other conditions.

After carefully taking a medical history and performing a thorough neurological exam, your doctor may order the following tests:

Blood. Blood tests are done to check for infections or other possible causes of muscle weakness.

Magnetic resonance imaging (MRI) of the brain and spine. MRI images or other tests can show signs of nerve cell degeneration and look for other causes of symptoms, such as structural abnormalities, spinal compression, and multiple sclerosis. sclerosis and spinal cord tumors.

Neurological study of sensory transmission. These tests use low currents to examine nerves and can show damage to nerve cells.

Electromyography (EMG). During this test, doctors insert an electrode needle through the skin into different muscles. The electrical activity of the muscle is assessed during contraction and at rest. This test can measure neuromuscular involvement, which can help to differentiate between amyotrophic lateral sclerosis and atrophy.

Cerebrospinal fluid analysis. Cerebrospinal fluid analysis during lumbar puncture of the lower back can help rule out multiple sclerosis and other causes of spasticity.

After other diseases are ruled out, your doctor can make a preliminary diagnosis of lateral sclerosis. Doctors sometimes wait 3 to 4 years before a definitive diagnosis is made because the early stages of amyotrophic lateral sclerosis (ALS) can resemble amyotrophic lateral sclerosis until superficial symptoms supplement a few years. afterward. It may be necessary to return to repeat testing more than 3 - 4 years before a diagnosis of lateral sclerosis is confirmed.

Treatments and drugs

Treatments focused primarily on amyotrophic lateral sclerosis relieve sclerosis and improve functional symptoms. There is no treatment to prevent, halt, or reverse lateral sclerosis. Treatment includes:

Medicine. Medicines available to relieve muscle spasms (spasticity) include baclofen, tizanidine (Zanaflex), diazepam (Valium), or clonazepam (KLONOPIN). These drugs are taken orally. If spasticity is not controlled with oral medication, your doctor may recommend surgically implanting a pump to deliver the drug baclofen directly to the spinal fluid (intrathecal baclofen).

Other medications may be prescribed to treat cramps or pain associated with spasticity, including phenytoin (Dilantin) or pain relievers.

Physical therapy. Stretching and strengthening exercises will help maintain muscle strength, flexibility, and range of motion, and to prevent joint immobility. Massage may also provide relief for lateral sclerosis symptoms.

Language therapy. If facial muscles are affected by lateral sclerosis, this therapy can help offset the effects of speech.

Assistive device. Periodic evaluation or occupational physical therapy may be required to determine if assistive devices, such as a walker, cane, or wheelchair are needed as lateral sclerosis progresses.

Lifestyle and remedy

Although there is no cure for primary lateral sclerosis, there are lifestyle choices that can be made to preserve muscle function:

Still working. Continue activities or programs as long as it is comfortable and safe to do so. Staying active will help keep existing functions and slow disease progression. Just be sure to stay safe, remembering that muscle weakness puts you at risk of tripping.

Eat a healthy diet. Because lateral sclerosis can cause slow activity levels, be sure to eat a nutritious diet to avoid excessive weight gain and increased stress on your joints.

Coping and supporting

Coping with the reality of an incurable disease can be challenging. To deal with illness and its effects, consider these tips:

Seek emotional support. Family and friends can be a great source of comfort and support when grappling with the emotional aspects of illness.

Because lateral sclerosis is an uncommon diagnosis, it can be challenging to find a local support group. However, a number of online discussion groups are available, and it can be helpful to see how others have coped with the disease.

Get professional help if necessary. When faced with a chronic illness, don't become overwhelmed. Seek professional advice for alternative perspectives, or if struggling with depression and need counseling about treatment.

Know and use available resources. If you reach a point where the disease significantly limits activity, ask your doctor about devices designed to help with independence. In addition, there are social services for people with disabilities. Try to learn all you can about available resources. Sometimes relying on the community for help can strengthen relationships.