Multiple Sclerosis (MS) is a chronic, progressive, degenerative disorder that affects nerve fibers in the brain and spinal cord. A fatty substance (myelin) surrounds and insulates nerve fibers and facilitates the conduction of nerve impulse transmissions.
MS is characterized by intermittent damage to myelin (demyelination) caused by the destruction of specialized cells (oligodendrocytes) that form the substance. Demyelination causes scarring and hardening (sclerosis) of nerve fibers usually in the spinal cord, brain stem, and optic nerves, which slows nerve impulses and results in weakness, numbness, pain, and vision loss.
Because different nerves are affected at different times, MS symptoms often worsen (exacerbate), improve, and develop in different areas of the body. Early symptoms of the disorder may include vision changes (blurred vision, blind spots) and muscle weakness. MS can progress steadily or cause acute attacks (exacerbation) followed by partial or complete reduction in symptoms (remission).
Types:
- Primary Progressive MS (PPMS): This type of MS is characterized by a gradual progression of the disease from its onset with no remissions at all.
- Relapsing Remitting MS (RRMS): This is characterized by relapses (exacerbations) during which time new symptoms can appear and old ones resurface or worsen. The relapses are followed by periods of remission, during which time the person fully or partially recovers from the deficits acquired during the relapse. Relapses can last for days, weeks, or months and recovery can be slow and gradual or almost instantaneous.
- Secondary Progressive MS (SPMS): Is initially similar to relapsing-remitting MS and eventually progresses to MS with no remission.
- Relapsing Progressive MS (RPMS): This form of MS follows a progressive course from onset, punctuated by relapses. There is significant recovery immediately following a relapse but between relapses there is gradual worsening of symptoms.
MS is the most common neurological cause of debilitation in young people and affects about 5000,000 people in the United States.
MS is more common in women and in Caucasians. The average age of onset is between 18 and 35, but the disorder may develop at any age. Children of parents with MS have a higher rate of incidence (30%-50%).
Risk Factors:
The specific cause of MS is not fully understood. It is usually classified as an auto-immune disease because it is widely accepted that it results from an abnormal immune system response. This response may be triggered by genetic, environmental, and viral factors that may initiate demyelination.
Signs and Symptoms:
Initial symptoms of MS may be brief and mild. The first serious attack usually lasts weeks or months and occurs between the ages of 20 and 40. The most common early symptoms include sensory abnormalities (tingling, numbness, itching, tightness, burning, shooting pain in the back and limbs [Lhermilte's sign], difficulty walking, eye pain, and vision loss).
Symptoms of the disease vary, depending on where the damage occurs, and range from minor physical annoyances to major disabilities. Common symptoms include:
- Balance and equilibrium abnormalities (dizziness, vertigo, uncoordinated movements, tremor)
- Bladder and bowel dysfunction (urgency, incontinence, nocturia, constipation)
- Behavioral changes (mood swings, depression)
- Cognitive dysfunction ( impaired memory, reasoning, concentration)
- Facial numbness
- Motor abnormalities (muscle weakness, spasm, spasticity)
- Sexual dysfunction (erectile dysfunction, sexual inactivity)
- Vision abnormalities (eye pain, vision loss in one eye, double vision [diplopia], involuntary eye movement [nystagmus])
Treatment:
The goals of treatment are to improve the quality of life by relieving symptoms caused by exacerbations (palliative treatment), slowing the course of the disease as much as possible, and providing psychological support. Treatment for MS varies.
In general, starting treatment early in the course of the disease and continuing treatment indefinitely is thought to provide the most benefit.
Corticosteroids are typically prescribed to treat exacerbations of MS.
Psychotherapy: MS support groups, counseling, and or antidepressants.
Rehabilitation: Physical therapy, occupational therapy, and speech therapy.
Prognosis:
Most people with MS have a relatively normal life span and life expectancy is about 35 years after onset. After 25 years, approximately two-thirds of patients remain mobile. The disorder eventually results in physical limitations in about 70% of patients.
Prevention:
There is no known preventative for MS.
