Multiple sclerosis
Multiple sclerosis (MS) is a chronic, often disabling disease that attacks the central nervous system. MS is not contagious, and most people with the disease are able to live productive lives. It is estimated that approximately 20,000 Australians have MS.
In MS, the protective sheath (known as myelin) that surrounds the nerve fibres in your brain and spinal cord becomes damaged. The damaged areas become scarred, leaving hardened, or sclerotic, patches — hence the name.
Once the myelin is destroyed, the nerve is no longer able to send messages down the length of its cell, in much the same way as the loss of insulating material surrounding an electrical wire will interfere with its ability to transmit signals.
What causes MS?
Despite a number of theories, the overall cause of MS remains unknown. It is generally accepted that MS is an autoimmune disorder; in other words, the body’s immune system attacks its own myelin. Genetic and environmental factors are believed to play a role. A number of viruses have been linked with MS, including Epstein-Barr virus, the virus that causes glandular fever (infectious mononucleosis). However, it is not clear how these viruses are involved in MS.
The first symptoms of MS usually occur between the ages of 20 and 40 years. It is about twice as common in women as in men, and it predominantly affects Caucasians living in temperate climates.
MS symptoms
The symptoms of MS depend on which nerves are affected. For example, if MS affects your optic nerve, your sight can be affected.
Symptoms vary widely from person to person and can include weakness in your limbs, numbness, tingling or painful sensations, impaired vision, fatigue, loss of balance and muscle coordination and tremors. Some people with MS may also develop bladder, bowel or sexual problems, thinking and memory problems, or partial or complete paralysis. Symptoms are often triggered or worsened by an increase in body temperature.
MS is an unpredictable disease. There is no way of knowing in any particular individual what will be the progress or severity of the illness, which part of the body will be affected, or the extent of recovery that will possibly occur after each demyelinating episode.
Course of MS
Just as the symptoms vary among individuals with MS, so does the course of the disease. Some people can be minimally affected, while others suffer severe progressive disability. However, the majority of people with MS do not become severely disabled.
In general, the course of MS tends to follow one of 2 patterns: the more common relapsing-remitting form and the progressive forms.
In the relapsing-remitting form of MS, people experience episodes where symptoms suddenly appear or get worse for a period of days to months, but then resolve fully or partially. The interval between these attacks can vary widely from weeks to years. Eventually, relapsing-remitting MS can develop into the progressive form of the disease, when the term ‘secondary progressive’ is used.
In the less common primary progressive form of the disease, people become steadily more disabled, without any recovery from or reversal of the disability.
MS treatment
As yet there is no cure for MS, but there are treatments available to treat MS attacks, modify the course of the underlying disease and relieve some symptoms.
Treatment for an MS attack
Treatments that aim to shorten and reduce the severity of an MS attack include oral and intravenous corticosteroids. These medicines work by reducing inflammation and suppressing the immune system.
If corticosteroids are not helpful then your doctor may suggest plasma exchange (plasmapheresis). This is a process a bit like kidney dialysis; a machine separates your blood cells from the blood fluid (plasma) and then the blood cells are mixed with a plasma-like fluid and returned to your body. It is not clear how plasma exchange helps in MS but it may remove immune chemicals that contribute to nerve cell damage.
Treatments to modify the course of MS
There have been some significant advances in treatments for MS and understanding of the MS disease process in recent years.
A number of medicines that specifically target the immune process in MS have become available. These medicines, known as immunomodulators or immunotherapy, aim to reduce the frequency of attacks and slow down the progress of MS. However, these treatments do not reverse any current symptoms.
Treatments to modify the course of MS include:
- Beta interferon 1a (Avonex and Rebif) and beta interferon 1b (Betaferon). Interferons are proteins produced naturally in the body that help to fight infections and regulate the immune system. Beta interferons have been shown to slow down the progress of MS by regulating the immune system. They are given by injection 1-3 times per week.
- Glatiramer (Copaxone). Doctors believe glatiramer blocks the immune system’s attack on myelin. It is given by injection once daily.
- Fingolimod (Gilenya). This is an immunomodulator that targets the immune cells involved in destroying myelin. It helps trap them in the lymph nodes, reducing the number that can reach the brain and spinal cord. Fingolimod is given orally once per day.
- Natalizumab (Tysabri). This is a monoclonal antibody that targets certain immune cells, stopping them moving from your bloodstream to the brain. It is given by intravenous infusion once a month. Natalizumab may increase the risk of a rare but very serious brain infection called progressive multifocal leucoencephalopathy, so your doctor may wish to monitor you for any signs of this.
Immunosuppressants are another group of drugs that have a broader effect in dampening down the immune system than the immunomodulators. Your specialist may offer an immunosuppressant for progressive MS if it does not respond to immunomodulators.
Treatments to relieve symptoms
Treatments that may help relieve MS symptoms include baclofen (e.g. Lioresal) or dantrolene (Dantrium) for muscle spasms and stiffness. Other medicines are available that can help relieve pain, bowel and bladder control problems, fatigue and depression.
Physical therapy such as stretching and strengthening exercises, and occupational therapy may also help you manage symptoms and stay active.
Stem cell therapy
Stem cell therapy is an experimental treatment for MS. Theoretically it might be able to prevent immune damage to the nervous system or help repair damaged myelin sheath. However, the safety and effectiveness of stem cell therapy in MS are unclear. A number of different types of stem cell therapy are being tested for MS in clinical research trials.
Last Reviewed: 03 August 2011
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