Multiple sclerosis (MS) is a nervous system disease that affects the brain and spinal cord. The immune system damages the myelin sheath, the protective layer surrounding your nerve cells. This damage disrupts or blocks the signals between your brain and your body, which lead to the symptoms of MS.
Symptoms of MS include:
- Fatigue – The National MS Society reports that about 80% of people with MS experience debilitating fatigue that interferes with work and home life.
- Numbness – This may be the first symptom experienced
- Visual disturbances – Blurred vision is another early onset symptom
- Spasticity – Involuntary muscle spasms are common in the legs, and occasionally, the arms
- Pain – One study found that 55% of people with MS had clinically significant pain at some time and almost half had chronic pain
Types of MS:
There are four basic types of MS, also known as disease courses:
Relapsing-remitting MS (RRMS) – This form of the disease is characterized by clearly defined attacks – also called relapses or exacerbations – lasting from days to weeks followed by periods of partial or complete recovery (remissions). During remissions, all symptoms may disappear, or some symptoms may continue and become permanent. This is the most common form of the disease. Approximately 85 percent of people with MS are initially diagnosed with RRMS.
Primary Progressive MS (PPMS) – This form of MS is characterized by worsening neurologic function from the onset of symptoms without early relapses or remissions. PPMS can be further characterized at different points in time as either active with an occasional relapse and/or evidence of new MRI activity or not active with progression and evidence of the disease worsening over time. Approximately 15 percent of people with MS are diagnosed with PPMS.
Secondary progressive MS (SPMS) –Most people diagnosed with RRMS will eventually transition to SPMS and experience a progressive worsening of neurologic function (accumulation of disability) over time.
Progressive-Relapsing MS (PRMS) – People with this type of the disease show clear progression in disability level from the onset, but also experience clear, acute relapses.
How is MS diagnosed?
Currently, there is no diagnostic test that can determine if a person has MS. To diagnose the disease, other causes of the symptoms must be excluded. Healthcare providers use the following criteria to make a diagnosis of MS, the healthcare provider must:
- Find evidence of damage in at least two separate areas of the central nervous system (CNS), which includes the brain, spinal cord and optic nerves AND
- Find evidence that the damage occurred at two different points in time AND
- Rule out all other possible diagnoses