Demyelinating Disorders

Females are more frequently diagnosed with multiple sclerosis (MS) than males. Researchers are looking at several possible explanations for why the immune system attacks central nervous system myelin, including:

• Fighting an infectious agent (e.g., a virus) that has components that mimic components of the brain (molecular mimicry)
• Destroying brain cells because they are unhealthy
• Mistakenly identifying normal brain cells as foreign

There is also something known as the blood-brain barrier, which separates the brain and spinal cord from the immune system. If there is a break in this barrier, it exposes the brain to the immune system. When this happens, the immune system may misinterpret structures in the brain, such as myelin, as “foreign.”

Research shows that genetic vulnerabilities combined with environmental factors may cause MS.

Multiple sclerosis (MS) is confirmed when symptoms and signs develop and are related to different parts of the nervous system at more than one interval and after other alternative diagnoses have been excluded.

Doctors use different tests to rule out or confirm the diagnosis. In addition to a complete medical history, physical examination and a detailed neurological examination, a doctor may recommend:

• MRI scans of the brain and spinal cord to look for the characteristic lesions of MS. A special dye or contrast agent may be injected into a vein to enhance brain images of the active MS lesions.
• Lumbar puncture (sometimes called a spinal tap) to obtain a sample of cerebrospinal fluid and examine it for proteins and inflammatory cells associated with the disease. Spinal tap analysis also can rule out diseases that may look like MS.
• Evoked potential tests, which use electrodes placed on the skin and painless electric signals to measure how quickly and accurately the nervous system responds to stimulation.

Several studies indicate that people who spend more time in the sun and those with relatively higher levels of vitamin D are less likely to develop MS or have a less severe course of disease and fewer relapses. Bright sunlight helps human skin produce vitamin D. Researchers believe that vitamin D may help regulate the immune system in ways that reduce the risk of MS or autoimmunity in general. People from regions near the equator, where there is a great deal of bright sunlight, generally have a much lower risk of MS than people from temperate areas such as the U.S. and Canada.

The symptoms of multiple sclerosis (MS) depend on the severity of the inflammatory reaction as well as the location and extent of the plaques, which primarily appear in the brain stem, cerebellum (involved with balance and coordination of movement, among other functions), spinal cord, optic nerves and the white matter around the brain ventricles (fluid-filled cavities).

Early MS symptoms often include:

• Vision problems such as blurred or double vision, or optic neuritis, which causes pain with eye movement and rapid vision loss
• Muscle weakness, often in the hands and legs, and muscle stiffness accompanied by painful muscle spasms
• Tingling, numbness or pain in the arms, legs, trunk or face
• Clumsiness, especially difficulty staying balanced when walking
• Bladder control problems
• Intermittent or constant dizziness

MS may also cause later symptoms, such as:

• Mental or physical fatigue that accompanies the early symptoms during an attack
• Mood changes such as depression or difficulty with emotional expression or control
• Cognitive dysfunction—problems concentrating, multitasking, thinking or learning, or difficulties with memory or judgment

Muscle weakness, stiffness and spasms may be severe enough to affect walking or standing. In some cases, MS leads to partial or complete paralysis, and the use of a wheelchair is not uncommon, particularly in individuals who are untreated or have advanced disease. Many people with MS find that weakness and fatigue are worse when they have a fever or when they are exposed to heat. MS exacerbations may occur following common infections.

Pain is rarely the first sign of MS, but pain often occurs with optic neuritis and trigeminal neuralgia, a disorder that affects one of the nerves that provides sensation to different parts of the face. Painful limb spasms and sharp pain shooting down the legs or around the abdomen can also be symptoms of MS.

Conditions associated with MS:

• Transverse myelitis (an inflammation of the spinal cord) may develop in those with MS. Transverse myelitis can affect spinal cord function over several hours to several weeks before partial or complete recovery. It usually begins as a sudden onset of lower back pain, muscle weakness, abnormal sensations in the toes and feet, or difficulties with bladder control or bowel movements. This can rapidly progress to more severe symptoms, including arm and/or leg paralysis. In most cases, people recover at least some function within the first 12 weeks after an attack begins.
• Neuromyelitis optica is a disorder associated with transverse myelitis as well as optic nerve inflammation (also known as optic neuritis). People with this disorder usually have abnormal antibodies (proteins that normally target viruses and bacteria) against a specific channel in optic nerves, the brain stem or spinal cord, called the aquaporin-4 channel. These individuals respond to certain treatments that are different from those commonly used to treat MS.
• Trigeminal neuralgia is a chronic pain condition that causes sporadic, sudden burning or shock-like facial pain. The condition is more common in young adults with MS and is caused by lesions in the brain stem, the part of the brain that controls facial sensation.
• Eye and vision problems are common in people with MS but rarely result in permanent blindness. Inflammation of the optic nerve (optic neuritis) or damage to the myelin that covers the nerve fibers in the visual system can cause blurred or grayed vision, temporary blindness in one eye, loss of normal color vision, loss of depth perception, or loss of vision in parts of the visual field. Uncontrolled horizontal or vertical eye movements (nystagmus), “jumping vision" (opsoclonus) and double vision (diplopia) are common in people with MS. Intravenous steroid medications, special eyeglasses and periodically resting the eyes may be helpful.
• Muscle weakness and spasticity is common in MS. Mild spasticity can be managed by stretching and exercising muscles using water therapy, yoga or physical therapy. Medications such as gabapentin or baclofen can reduce spasticity. It is very important that people with MS stay physically active because physical inactivity can contribute to worsening stiffness, weakness, pain, fatigue and other symptoms.
• Tremor, or uncontrollable shaking, develops in some people with MS. Assistive devices and weights attached to utensils or even limbs are sometimes helpful for people with tremor. Deep brain stimulation and drugs, such as clonazepam, may also be useful.
• Problems with walking and balance occur in many people with MS. The most common walking problem is ataxia—unsteady, uncoordinated movements—due to damage to the areas of the brain that coordinate muscle balance. People with severe ataxia generally benefit from the use of a cane, walker or other assistive device. Physical therapy also can reduce walking problems. The FDA has approved the drug dalfampridine to improve walking speed in people with MS.
• Fatigue is a common symptom of MS and may be both physical (tiredness in the arms or legs) and cognitive (slowed processing speed or mental exhaustion). Daily physical activity programs of mild to moderate intensity can significantly reduce fatigue, although people should avoid excessive physical activity and minimize exposure to hot weather conditions or ambient temperature. Other drugs that may reduce fatigue include amantadine, methylphenidate and modafinil. Occupational therapy can help people learn how to walk using an assistive device or in a way that saves physical energy. Stress management programs, relaxation training, membership in an MS support group, or individual psychotherapy may help some people.
• Pain from MS can be felt in different parts of the body. Trigeminal neuralgia (facial pain) is treated with anticonvulsant or antispasmodic drugs, or less commonly, painkillers. Central pain, a syndrome caused by damage to the brain and/or spinal cord, can be treated with gabapentin and nortriptyline. Treatments for chronic back or other musculoskeletal pain may include heat, massage, ultrasound and physical therapy.
• Problems with bladder control and constipation may include urinary frequency, urgency or the loss of bladder control. A small number of individuals retain large amounts of urine. Medical treatments are available for bladder-related problems. Constipation is also common and can be treated with a high-fiber diet, laxatives and stool softeners.
• Sexual dysfunction can result from damage to nerves running through the spinal cord. Sexual problems may also stem from MS symptoms such as fatigue, cramped or spastic muscles, and psychological factors. Some of these problems can be corrected with medications. Psychological counseling may be helpful.
• Clinical depression is frequent among people with MS. MS may cause depression as part of the disease process and chemical imbalance in the brain. Depression can intensify symptoms of fatigue, pain and sexual dysfunction. It is most often treated with cognitive behavioral therapy and selective serotonin reuptake inhibitor (SSRI) antidepressant medications, which are less likely than other antidepressant medications to cause fatigue.
• Inappropriate and involuntary expressions of laughter, crying or anger—symptoms of a condition called pseudobulbar affect—sometimes are associated with MS. These expressions are often incongruent with mood; for example, people with MS may cry when they are actually happy, or laugh when they are not especially happy. The combination treatment of the drugs dextromethorphan and quinidine can treat pseudobulbar affect, as can other drugs such as amitriptyline or citalopram.
• Cognitive impairment—a decline in the ability to think quickly and clearly and to remember easily—affects up to 75 percent of people with MS. These cognitive changes may appear at the same time as the physical symptoms, or they may develop gradually over time. Drugs such as donepezil may be helpful in some cases.

Here are the typical symptoms of other types of demyelinating disorders:

• Chronic inflammatory demyelinating polyneuropathy (CIDP): Tingling or no feeling in fingers and toes, weakness of arms and legs, loss of deep tendon (muscle stretch) reflexes, fatigue or feeling tired, unusual feelings in the body, difficulty walking, falls, hand muscle weakness, and spontaneous pain sensation
• Acute disseminated encephalomyelitis: Loss of vision in one or both eyes due to inflammation of the optic nerve, weakness that may be severe, difficulty coordinating intended (voluntary) movement such as walking, rapid onset of fever, some degree of impairment of consciousness (may be as severe as coma) 
• Balo’s disease (concentric sclerosis): High fever, headache, trouble talking or understanding information, memory loss, muscle spasms, seizures, paralysis
• Charcot-Marie-Tooth (CMT) disease: Weakness in legs, ankles and feet; loss of muscle mass in legs and feet; trouble raising legs and moving ankles; changes to feet (higher arches or curled toes); trouble walking or running; tripping; and falling
• Guillain-Barre syndrome (GBS): Tingling in fingers, toes, ankles or wrists; weakness in legs and upper body; trouble walking or climbing stairs; bowel or bladder problems; trouble moving face, speaking or chewing.
• HTLV-I associated myelopathy (HAM): Weakness in legs, numbness or tingling, stiff muscles, muscle spasms, bladder problems, constipation, double vision, deafness, coordination problems, tremors
• Neuromyelitis optica (Devic’s disease): Blurred vision, loss of eyesight, eye pain, weak or numb arms or legs, bladder and bowel problems, vomiting, uncontrollable hiccups
• Schilder’s disease: Weakness on one side of the body, slow movements, seizures, trouble speaking, vision and hearing problems, memory problems, change in personality, weight loss
• Transverse myelitis: Problems moving legs, bowel and bladder problems, lower back pain, muscle weakness, sensitivity to touch, tingling or numbness in toes, fatigue

There is no single test used to diagnose multiple sclerosis (MS). The disease is confirmed when symptoms and signs develop and are related to different parts of the nervous system at more than one interval and after other alternative diagnoses have been excluded.

Doctors use different tests to rule out or confirm the diagnosis. In addition to a complete medical history, physical examination and a detailed neurological examination, a doctor may recommend:

• MRI scans of the brain and spinal cord to look for the characteristic lesions of MS. A special dye or contrast agent may be injected into a vein to enhance brain images of the active MS lesions.
• Lumbar puncture (sometimes called a spinal tap) to obtain a sample of cerebrospinal fluid and examine it for proteins and inflammatory cells associated with the disease. Spinal tap analysis also can rule out diseases that may look like MS.
• Evoked potential tests, which use electrodes placed on the skin and painless electric signals to measure how quickly and accurately the nervous system responds to stimulation.

Screenings for other demyelinating disorders like chronic inflammatory demyelinating polyneuropathy (CIDP) may be a lumbar puncture, a nerve conduction study (electromyogram) to test nerve function, a CT scan, and blood or urine tests.

There is no cure for multiple sclerosis (MS), but there are treatments that can reduce the number and severity of relapses and delay the long-term disability progression of the disease.

• Corticosteroids, such as intravenous (infused into a vein) methylprednisolone, are prescribed over the course of three to five days. Intravenous steroids quickly and potently suppress the immune system and reduce inflammation. They may be followed by a tapered dose of oral corticosteroids. Clinical trials have shown that these drugs hasten recovery from MS attacks but do not alter the long-term outcome of the disease.
• Plasma exchange (plasmapheresis) can treat severe flare-ups in people with relapsing forms of MS who do not have a good response to methylprednisolone. Plasma exchange involves taking blood out of the body and removing components in the blood’s plasma that are thought to be harmful. The rest of the blood, plus replacement plasma, is then transfused back into the body. This treatment has not been shown to be effective for secondary progressive or chronic progressive MS.

Current therapies approved by the U.S. Food and Drug Administration (FDA) for MS are designed to modulate or suppress the inflammatory reactions of the disease. They are most effective for relapsing-remitting MS at early stages of the disease.

Injectable medications include:

• Beta interferon drugs, which are among the most common medications used to treat MS. Interferons are signaling molecules that regulate immune cells. Potential side effects of these drugs include flu-like symptoms (which usually fade with continued therapy), depression or elevation of liver enzymes. Some individuals will notice a decrease in the effectiveness of the drugs after 18 to 24 months of treatment. If flare-ups occur or symptoms worsen, doctors may switch treatment to alternative drugs.
• Glatiramer acetate, which changes the balance of immune cells in the body, but how it works is not entirely clear. Side effects are usually mild and consist of local injection site reactions or swelling.

Infusion treatments include:

• Natalizumab, which is administered intravenously once a month. It works by preventing cells of the immune system from entering the brain and spinal cord. It is very effective but is associated with an increased risk of a serious and potentially fatal viral infection of the brain called progressive multifocal leukoencephalopathy (PML). Natalizumab is generally recommended only for individuals who have not responded well to or who are unable to tolerate other first-line therapies.
• Ocrelizumab, which is administered intravenously every six months and treats adults with relapsing or primary progressive forms of MS. It is the only FDA-approved disease-modifying therapy for primary-progressive MS. The drug targets the circulating immune cells that produce antibodies, which also play a role in the formation of MS lesions. Side effects include infusion-related reactions and increased risk of infections. Ocrelizumab may increase the risk of cancer as well.
• Alemtuzumab, which is administered for five consecutive days, followed by three days of infusions one year later. It targets proteins on the surface of immune cells. Because this drug increases the risk of autoimmune disorders, it is recommended for those who have had inadequate responses to two or more MS therapies.
• Mitoxantrone, which is administered intravenously four times a year, has been approved for especially severe forms of relapsing-remitting and secondary progressive MS. Side effects include the development of certain types of blood cancers in up to one percent of those with MS, as well as with heart damage. This drug should be considered as a last resort to treat people with a form of MS that leads to rapid loss of function and for whom other treatments did not work.

Oral treatments include:

• Fingolimod, a once-daily medication that reduces the MS relapse rate in adults and children. It is the first FDA-approved drug to treat MS in adolescents and children ages 10 years and older. The drug prevents white blood cells called lymphocytes from leaving the lymph nodes and entering the blood, brain and spinal cord. Fingolimod may result in a slow heart rate and eye problems when first taken. Fingolimod can also increase the risk of infections, such as herpes virus infections, or in rare cases be associated with PML.
• Dimethyl fumarate, a twice-daily medication used to treat relapsing forms of MS. Its exact mechanism of action is not currently known. Side effects of dimethyl fumarate are flushing, diarrhea, nausea and lowered white blood cell count. 
• Teriflunomide, a once-daily medication that reduces the rate of proliferation of activated immune cells. Teriflunomide side effects can include nausea, diarrhea, liver damage and hair loss.
• Cladribine, which is administered as two courses of tablets about one year apart. Cladribine targets certain types of white blood cells that drive immune attacks in MS. The drug may increase the risk of developing cancer and should be considered for individuals who have not responded well to other MS treatments.
• Diroximel fumarate, a twice-daily drug similar to dimethyl fumarate (brand name Tecfidera) but with fewer gastrointestinal side effects. Scientists suspect these drugs, which have been approved to treat secondary progressive MS, reduce damage to the brain and spinal cord by making the immune response less inflammatory, although their exact mechanism of action is poorly understood.
• Siponimod tablets (Mayzent), which are taken orally and have a similar mechanism of action to fingolimod. Siponimod has been approved by the FDA to treat secondary-progressive MS.

Clinical trials have shown that cladribine, diroximel fumarate and dimethyl fumarate decrease the number of relapses, delay the progress of physical disability, and slow the development of brain lesions.

Multiple sclerosis (MS) causes a variety of symptoms that can interfere with daily activities but can usually be treated or managed. Many of these issues are best treated by neurologists who have advanced training in the treatment of MS and who can prescribe specific medications to treat these problems.

Eye and vision problems are common in people with MS but rarely result in permanent blindness. Inflammation of the optic nerve (optic neuritis) or damage to the myelin that covers the nerve fibers in the visual system can cause blurred or grayed vision, temporary blindness in one eye, loss of normal color vision, loss of depth perception, or loss of vision in parts of the visual field. Uncontrolled horizontal or vertical eye movements (nystagmus), “jumping vision" (opsoclonus) and double vision (diplopia) are common in people with MS. Intravenous steroid medications, special eyeglasses and periodically resting the eyes may be helpful.

Muscle weakness and spasticity is common in MS. Mild spasticity can be managed by stretching and exercising muscles using water therapy, yoga or physical therapy. Medications such as gabapentin or baclofen can reduce spasticity. It is very important that people with MS stay physically active because physical inactivity can contribute to worsening stiffness, weakness, pain, fatigue and other symptoms.

Tremor, or uncontrollable shaking, develops in some people with MS. Assistive devices and weights attached to utensils or even limbs are sometimes helpful for people with tremor. Deep brain stimulation and drugs, such as clonazepam, may also be useful.

Problems with walking and balance occur in many people with MS. The most common walking problem is ataxia—unsteady, uncoordinated movements—due to damage to the areas of the brain that coordinate muscle balance. People with severe ataxia generally benefit from the use of a cane, walker or other assistive device. Physical therapy also can reduce walking problems. The FDA has approved the drug dalfampridine to improve walking speed in people with MS.

Fatigue is a common symptom of MS and may be both physical (tiredness in the arms or legs) and cognitive (slowed processing speed or mental exhaustion). Daily physical activity programs of mild to moderate intensity can significantly reduce fatigue, although people should avoid excessive physical activity and minimize exposure to hot weather conditions or ambient temperature. Other drugs that may reduce fatigue include amantadine, methylphenidate and modafinil. Occupational therapy can help people learn how to walk using an assistive device or in a way that saves physical energy. Stress management programs, relaxation training, membership in an MS support group, or individual psychotherapy may help some people.

Pain from MS can be felt in different parts of the body. Trigeminal neuralgia (facial pain) is treated with anticonvulsant or antispasmodic drugs, or less commonly, painkillers. Central pain, a syndrome caused by damage to the brain and/or spinal cord, can be treated with gabapentin and nortriptyline. Treatments for chronic back or other musculoskeletal pain may include heat, massage, ultrasound and physical therapy.

Problems with bladder control and constipation may include urinary frequency, urgency or the loss of bladder control. A small number of individuals retain large amounts of urine. Medical treatments are available for bladder-related problems. Constipation is also common and can be treated with a high-fiber diet, laxatives and stool softeners.

Sexual dysfunction can result from damage to nerves running through the spinal cord. Sexual problems may also stem from MS symptoms such as fatigue, cramped or spastic muscles and psychological factors. Some of these problems can be corrected with medications. Psychological counseling may be helpful.

Clinical depression is frequent among people with MS. MS may cause depression as part of the disease process and chemical imbalance in the brain. Depression can intensify symptoms of fatigue, pain and sexual dysfunction. It is most often treated with cognitive behavioral therapy and selective serotonin reuptake inhibitor (SSRI) antidepressant medications, which are less likely than other antidepressant medications to cause fatigue.

Inappropriate and involuntary expressions of laughter, crying or anger—symptoms of a condition called pseudobulbar affect—sometimes are associated with MS. These expressions are often incongruent with mood; for example, people with MS may cry when they are actually happy or laugh when they are not especially happy. The combination treatment of the drugs dextromethorphan and quinidine can treat pseudobulbar affect, as can other drugs such as amitriptyline or citalopram.

Cognitive impairment—a decline in the ability to think quickly and clearly and to remember easily—affects up to 75 percent of people with MS. These cognitive changes may appear at the same time as the physical symptoms, or they may develop gradually over time. Drugs such as donepezil may be helpful in some cases.

With most demyelinating disorders, those who get early treatment and manage their disorder carefully can experience a higher quality of life. Upon onset of any symptoms—especially numbness, weakness, spasms or tingling in the limbs—should see a doctor right away and seek a diagnosis.