Multiple sclerosis: what is it, symptoms, treatment, prognosis

What is multiple sclerosis?

Multiple sclerosis(RS) - chronic autoimmune disease, in which damage and destruction of the myelin sheath (the substance that covers most of nerve fibers) and located underneath the nerve fibers of the brain, optic nerves and spinal brain.

In most people with multiple sclerosis, periods of relatively good health alternate with episodes of worsening symptoms, but the disease gradually worsens over time. Patients may have impaired vision, unusual sensations, and movements become weak and awkward.

Usually, doctors diagnose multiple sclerosis based on symptoms, physical examination results, and magnetic resonance imaging. Treatment includes corticosteroids, drugs that prevent the immune system from breaking down the myelin sheath, and drugs that relieve symptoms. The disease does not affect life expectancy, except in very severe cases.

The disease is called multiple sclerosis because the destruction of the myelin sheaths causes scarring (sclerosis) in many parts of the body. This destruction of the myelin sheath is called demyelination. Sometimes nerve fibers (axons) that send signals are also damaged. Over time, due to the destruction of axons, the brain can shrink in size.

In the world, about 2.3-2.5 million suffer from multiple sclerosis, mostly young people. In Russia - more than 150 thousand.

Most often, multiple sclerosis begins between the ages of 20-40, but it can develop at any age between the ages of 15 and 60. The disease is more common in women. Multiple sclerosis is rare in children.

In most patients, periods of relatively well-being (remission) are interspersed with periods of worsening symptoms (exacerbation or relapse). Relapses are of varying severity. During remissions, the patient's capabilities are restored quite well, but, as a rule, not completely. Thus, multiple sclerosis progresses slowly over time.

Causes and risk factors

The cause of multiple sclerosis is unknown, but a possible explanation is that patients in the first years of life were infected with a virus (presumably the herpes virus or retrovirus) or were exposed to some unknown substance that somehow prompted the immune system to fight against the body's own tissues (autoimmune reaction). An autoimmune reaction causes inflammation, which destroys the myelin sheath and the nerve fibers that surround it.

Genes can play a role. For example, the presence of multiple sclerosis in parents or siblings increases the risk of the disease by several times. In addition, multiple sclerosis is more likely to develop in people who have certain genetic markers on their cell surfaces, called human leukocyte antigens. Normally, these markers allow the body to distinguish its cells from those of others and to know what to fight against.

The environment plays a role in the development of multiple sclerosis. The likelihood of developing the disease depends on where the person lived for the first 15 years. It goes like this:

• In people raised in temperate climates, about 1 in 300 to 1,000 people develop the disease;
• In people raised in tropical climates, only 1 in 5,000–20,000 people develop the disease;
• The disease occurs much less frequently in people who grew up near the equator.

These differences may vary by level vitamin D. When the sun's rays hit the skin, it produces vitamin D. This is why people raised in temperate climates have less vitamin D. People with low vitamin D levels are more likely to have multiple sclerosis. In addition, patients with the disease and low vitamin D levels are also more likely to have more severe symptoms. It is not known, however, how vitamin D protects against this disease.

From the place in which a person spent the subsequent years of his life - regardless of the climate - the likelihood of developing multiple sclerosis does not depend.

Smoking cigarettes also increases the likelihood of developing multiple sclerosis. The reason is unknown.

Multiple sclerosis symptoms

Symptoms can be very different in different patients and at different times in the same patient. They depend on which nerve fibers are demyelinated.

• If the nerve fibers that carry sensory information are demyelinated, the patient's sensitivity changes (sensory symptoms).
• If the nerve fibers that control the muscles are affected, it is difficult for the person to move (motor symptoms).

- The course of multiple sclerosis.

Multiple sclerosis progresses and regresses unpredictably. There are, however, several types of the course of the disease:

• Relapsing-remitting. Relapses (symptoms get worse) alternate with remissions (symptoms don't get worse or worse). Remissions can last for months or years. Relapses can occur on their own or be triggered by an infection, such as the flu.
• Primarily progressive. The disease progresses steadily without remission and obvious relapses, although there may be periods during which the disease does not progress.
• Secondary progressive. Initially, relapses alternate with remissions (relapsing-remitting course), but then this course is replaced by a steady progression.
• Progressive with exacerbations. The disease progresses evenly, but against the background of progression, unexpected exacerbations occur. This type of disease is rare.

On average, one relapse occurs every 2 years, but the frequency can vary greatly.

- Early symptoms of multiple sclerosis.

Sometimes, even before the disease is diagnosed, the patient begins with vague symptoms of demyelination of the nerve fibers of the brain. The most common early symptoms are as follows:

• tingling, numbness, pain, burning, and itching in the arms, legs, trunk, or face, and sometimes a decrease in the sensation of touch;
• loss of strength and stamina in an arm or leg that may become stiff;
• visual impairment.

Vision may become weak or blurry. Usually, patients begin to see objects located directly in front of them worse (central vision). Peripheral vision (objects located on the side) suffers less. People with multiple sclerosis may also experience the following visual impairments:

• Internuclear ophthalmoplegia. The nerve fibers that coordinate the horizontal movement of the eyes (looking from side to side) are damaged. One eye cannot turn inward, which causes double vision when looking away from the affected eye. The unaffected eye may involuntarily make rapid, repetitive movements in one direction, and then slowly come back (this symptom is called "nystagmus»).
• Optic neuritis (inflammation of the optic nerve). There may be partial loss of vision in one eye and pain when moving that eye.

Walking and balance may be affected. Dizziness and vertigo, as well as fatigue, are common.

Excessive heat, such as hot weather, hot bath or shower, or fever, can temporarily worsen symptoms.

When the back of the spinal cord in the cervical region is affected, you may feel an electric shock or tingling sensation when you try to tilt your head forward. The sensation extends down the back, both legs, one arm, or one half of the body (Lermitte's sign). This sensation is usually very short-lived and disappears when the neck is straightened. It often persists as long as the head is tilted forward.

- Late symptoms of multiple sclerosis.

As MS progresses, movements become unsteady, unsteady, and weak. The patient becomes partially or completely paralyzed. Weak muscles can contract involuntarily (spasticity), sometimes causing painful spasms. Muscle weakness and spasticity can interfere with walking; eventually the patient may not be able to walk, even with crutches or a walker. Some people may be confined to a wheelchair. People who are unable to walk may experience osteoporosis (decrease in bone density).

Speech slows down, becomes fuzzy and uncertain.

Patients with multiple sclerosis may lose the ability to control their emotions and may laugh or cry out of place. Distributed depression, weak thinking disorder may occur.

Multiple sclerosis often affects the nerves that control urination or bowel movements. As a result, most people with multiple sclerosis have urinary control problems such as:

• frequent and strong urge to urinate;
• spontaneous urination (urinary incontinence);
• difficulty starting urination;
• inability to completely empty the bladder (urinary retention).

Leftover urine can be a breeding ground for bacteria, which increases the risk of developing urinary tract infections.

Patients may also have constipation or, sometimes, involuntary bowel movement (fecal incontinence).

In rare cases, at a late stage of the disease, dementia.

If relapses become more frequent, the patient's physical capabilities are increasingly reduced, sometimes irreversibly.

Diagnostics

Because symptoms vary so much, the doctor may not recognize the disease in its early stages. A doctor suspects multiple sclerosis if vision suddenly becomes blurry in a relatively young person, double vision, unusual sensations appear in different parts of the body, or it becomes difficult for him to make movements. Appearing and disappearing symptoms and intermittent relapses and remissions speak in favor of the diagnosis. The patient needs to clearly describe to the doctor all the symptoms that are present, especially if the symptoms are absent during the visit to the doctor.

If doctors suspect multiple sclerosis, they do a thorough assessment of the nervous system (neurologic examination) during a physical exam. They examine the fundus of the eye (retina) with an ophthalmoscope. The optic nerve head (the place where the optic nerve exits to the surface of the retina) may be unusually pale, indicating damage to the optic nerve.

Of the imaging tests, magnetic resonance imaging (MRI) is the best choice for detecting multiple sclerosis. It usually allows you to find areas of demyelination in the brain and spinal cord. An MRI is done after gadolinium (a paramagnetic contrast agent) is injected into the bloodstream. After an injection of gadolinium, it is easier to distinguish areas of recent demyelination and active inflammation from areas that have been demyelinated long ago. Sometimes, demyelination is detected during an MRI scan for another reason, before any symptoms of multiple sclerosis appear.

- Additional examinations.

The diagnosis of multiple sclerosis is made based on current symptoms, history of relapses and remissions, physical examination, and MRI. If this, however, is not possible, the doctor conducts additional examinations:

• Lumbar puncture (lumbar puncture). A sample of cerebrospinal fluid is taken from the patient for analysis. The protein content of this liquid can be increased. In the majority of patients with multiple sclerosis, the content of antibodies is increased and characteristic antibodies (oligoclonal groups) are observed.
• Evoked responses. In this examination, certain areas of the brain are excited by external stimuli, for example, flashes of light, and the electrical activity of the brain that arises in response is recorded. In people with multiple sclerosis, the brain's response to stimulation may be slowed down because demyelinated nerve fibers cannot conduct nerve signals normally. This examination also detects minor damage to the optic nerve.

Other tests help doctors distinguish multiple sclerosis from conditions that cause similar symptoms, such as AIDS, tropical spastic paraparesis, vasculitis, arthritis of the neck, Guillain-Barré syndrome, hereditary ataxia, lupus, Lyme disease, rupture of the intervertebral disc, syphilis and spinal cord cyst (syringomyelia). For example, blood tests are needed to rule out Lyme disease, syphilis, AIDS, tropical spastic paraparesis, and lupus. Imaging studies rule out neck arthritis, intervertebral disc rupture, and syringomyelia.

Treatment

Treatment includes the following:

• Corticosteroids;
• Medicines that prevent the immune system from breaking down the myelin sheath
• Means for controlling symptoms.

The existing methods of treatment help different patients in different ways.

- Corticosteroids.

For an acute attack, corticosteroids are most commonly used. They help because they suppress the immune system. They are given for short periods of time to quickly relieve symptoms (such as loss of vision, strength, or coordination) when symptoms interfere with the patient's functioning. Prednisone can be taken as a pill, and methylprednisolone can be given intravenously. Although corticosteroids can shorten the relapse time and slow the progression of multiple sclerosis, they cannot stop the progression.

Because corticosteroids have many side effects, they are rarely long-term prescribed. These side effects include increased susceptibility to infections, diabetes, weight gain, fatigue, osteoporosis, and ulcers. Treatment with corticosteroids is started and stopped as needed.

- Medicines to help control the immune system.

Also commonly used are drugs that prevent the immune system from destroying the myelin sheath. These medications reduce the number of future relapses. These include:

• Interferon beta injections reduce the frequency of relapses and allow to postpone disability.
• Glatiramer acetate injections have a similar effect on patients with mild multiple sclerosis.
• Mitoxantrone, a chemotherapy drug, reduces relapse rates and slows the progression of the disease. This medication damages the heart, so it is prescribed for no more than 2 years and only when other medicines fail.
• Natalizumab - an antibody that is administered intravenously as an infusion once a month. It is better than other drugs in reducing relapse rates and better at preventing further brain damage. However, natalizumab may increase the risk of a rare fatal infection of the brain and spinal cord (progressive multifocal leukoencephalopathy).
• Alemtuzumab (which is used to treat leukemia) is effective for the treatment of multiple sclerosis, which has a relapsing course (relapsing-remitting and progressive-relapsing course). It is administered intravenously. However, it increases the risk of serious autoimmune diseases and certain types of cancer. Therefore, alemtuzumab is usually used only when two or more drugs have failed.
• When other drugs do not work, it can sometimes be helpful immunoglobulin intravenously once a month. Immunoglobulin consists of antibodies obtained from the blood of people with normal immune systems.
• For the treatment of recurrent forms of multiple sclerosis, you can use fingolimod, teriflunomide and dimethyl fumarate. These drugs can be taken by mouth. Fingolimod and dimethyl fumarate also increase the risk of progressive multifocal leukoencephalopathy, although the risk is significantly less than with natalizumab.
• Ocrelizumab - a monoclonal antibody that is used to treat recurrent or primary progressive forms of multiple sclerosis. It is prescribed as a vein infusion every 6 months. It can cause infusion reactions, which may include rash, itching, difficulty breathing, throat swelling, dizziness, low blood pressure, and heart palpitations.

Drugs that increase the risk of progressive multifocal leukoencephalopathy (natalizumab, fingolimod, and dimethyl fumarate) are used only by trained physicians. Patients who are prescribed these drugs should be periodically screened for progressive multifocal leukoencephalopathy. Blood tests are done periodically for the John Cunningham virus, which causes progressive multifocal leukoencephalopathy.

- Other types of treatment.

For severe relapses that cannot be relieved with corticosteroids, some experts recommend plasmapheresis. However, the benefits of plasmapheresis have not yet been proven. This treatment consists in taking blood from the patient, removing harmful antibodies from it, after which the blood is transfused back to the patient.

In severe, difficult to treat forms of the disease, stem cell transplantation performed in specialized centers can provide some benefit.

- Symptom control.

Other medications may be used to relieve specific symptoms:

• Muscle spasms: The muscle relaxants baclofen or tizanidine.
• Urinary incontinence: Oxybutynin, tamsulosin, or another drug, depending on the type of incontinence.
• Pain caused by nerve damage: Anticonvulsants (such as gabapentin, pregabalin, or carbamazepine), sometimes tricyclic antidepressants (such as amitriptyline).
• Tremors: The beta-blocker propranolol.
• Fatigue: Amantadine (used to treat Parkinson's disease) or, less commonly, drugs used to treat excessive sleepiness (such as modafinil, armodafinil, or amphetamine).
• Depression: Antidepressants such as sertraline or amitriptyline, counseling or consultation along with antidepressants.
• Constipation: Regular use of stool softeners and laxatives.

Patients with urinary retention can learn to insert a catheter and thus empty their bladder.

- General recommendations.

People with multiple sclerosis often lead an active life, although they get tired easily and may not be able to cope with a busy schedule. Encouragement and encouragement support.

Regular exercise, such as cycling, walking, swimming, and stretching, reduces spasticity and maintains cardiovascular, muscle, and mental health.

Physical therapy maintains the ability to maintain balance and walk, reduces spasticity and weakness, and increases range of motion. Patients should walk on their own as long as they can. This improves their quality of life and helps prevent depression.

High temperatures should be avoided, such as not taking hot showers or baths, because high temperatures can worsen symptoms. Smokers should quit smoking.

Because people with low vitamin D levels have more severe forms of multiple sclerosis, and because taking vitamin D can reduce the risk of osteoporosis, doctors usually recommend that such patients take vitamin supplements D. It is currently being investigated whether vitamin D supplementation may slow the progression of multiple sclerosis.

Patients who find it difficult to move due to weakness may develop bedsorestherefore, they and their caregivers need to take measures to prevent pressure ulcers.

If the patient's physical capabilities are limited, occupational therapists, physical therapists and speech therapists can help him with rehabilitation. They can teach patients to function despite the physical limitations caused by multiple sclerosis. Social workers can recommend services and equipment and help organize them.

Forecast

Disorders caused by multiple sclerosis and the rate at which it progresses vary greatly and unpredictably. The duration of remission can be from several months to 10 years or more. However, in some people, for example, in men, who become ill in middle age and have frequent relapses, the onset of disability is possible quickly. However, approximately 75% of people with multiple sclerosis never need to use a wheelchair, and approximately 40% lead a normal life.

Smoking cigarettes can accelerate the progression of the disease.

Multiple sclerosis does not affect life expectancy except in very severe cases.