Multiple sclerosis (MS)
What is multiple sclerosis?
Multiple sclerosis (MS) is a neurological condition of the brain and spinal cord, affecting muscle control, vision, balance and causing fatigue, loss of sensation or numbness.
MS is an auto-immune disease. The body's immune system is thought to turn on itself in MS, attacking the covering of nerves, called the myelin sheath, meaning signals to and from the brain can be disrupted. MS gets its name from the build-up of scar tissue (sclerosis) in the brain and/or spinal cord.
MS affects around 100,000 people in the UK. Most people receive an MS diagnosis between the ages of 20 and 40. The condition affects around three times as many women as it does men.
What causes MS?
No one is sure what causes the body's immune system to go wrong. Some scientists believe that it is a combination of genetics and something in the environment to which the person was exposed to early in life.
A lack of sunlight may be a factor, as MS is more common in countries further from the equator. Sunlight is how the body gets most of its vitamin D. There's also some evidence that a lack of vitamin D could contribute to MS.
There has also been research into viruses triggering MS. However, no single virus has yet been identified as a cause. There is some evidence that the Epstein Barr virus behind glandular fever may be factor.
What are the symptoms of MS?
MS symptoms vary from person to person and can change over time in the same person. Not all symptoms will be experienced at the same time. The most common early symptoms include:
As the disease progresses, symptoms may include muscle stiffness ( spasticity), pain, difficulty controlling urination, or problems with cognition.
How is MS diagnosed?
Making the diagnosis of MS isn't easy because the symptoms are vague and can come and go. A diagnosis can take several months. If your GP suspects that you may have MS, he or she will refer you to a neurologist for further investigations. A neurological examination will be carried out and tests arranged, including:
- Magnetic resonance imaging (MRI) of the brain and spinal cord can show areas of demyelination (lesions)
- Evoked potentials are measurements of electrical activity from the brain and nerves. This is a painless procedure, and if demyelination has occurred, this test can demonstrate that the transmission of messages along the nerves is slower than normal.
- A lumbar puncture (or spinal tap) involves inserting a needle into the lumbar spine under local anaesthetic to draw off a small amount of the cerebrospinal fluid that surrounds the brain and spinal cord. Testing the fluid may show antibodies that show the immune system in the central nervous system has been overactive. It is not performed routinely but is reserved for cases where the diagnosis is not entirely clear.
There are other tests that a neurologist may perform, mainly to exclude other conditions that may mimic MS.