Diagnosing Multiple Sclerosis

Posted on: 7 February 2019


Multiple sclerosis (MS) can be a difficult disease to diagnose since it can present with different symptoms and may have an unpredictable course. Diagnosing MS promptly can give you the best chance at reducing permanent damage and long-term disability.


People with MS may have any number of neurological systems. Even symptoms, such as visual disturbances or gastrointestinal problems may ultimately be neurological in nature. Any usual symptoms should be evaluated by your doctor or in an urgent care setting, if warranted. For example, numbness, paralysis, or slurred speech could easily be caused by a stroke or other life-threatening condition and requires prompt diagnosis at an emergency department. Once medical professionals can exclude a stroke, they will likely perform other tests to identify the problem and may request a consultation from the neurology department.

Diagnostic Tests

Your first imaging test will likely be a CT, since it is fast and has fewer limitations than MRI. Brain damage associated with a stroke or evidence of a tumor might be seen on CT. If your CT is negative, MRI might yield more definitive answers. People with MS might be diagnosed after their MRI reveals evidence of brain lesions. When MS is suspected, another test that may be used to aid in diagnosis is an evoked potential test. This test allows doctors to determine your nerve's reaction to stimuli. Since MS causes demyelination of the nerves, it slows or inhibits electrical impulses from traveling down the nerve. This explains the symptoms observed in some people with MS, such as problems walking, talking, or issues with bowel and urinary incontinence.

Lab Work

Many types of lab tests are more exclusionary than confirmation of MS. Standard blood tests, such as a complete blood count or tests for inflammation, may indicate other problems that can mimic MS. Abnormally high white cells could indicate an infection or be associated with autoimmune diseases like MS. Tests that identify inflammation, such as ESR or CRP, might be high in people with autoimmune diseases. A spinal tap might be ordered if an infection or MS is suspected. Since cerebrospinal fluid should be sterile and clear, anything found in the sample could be telling. The presence of antibodies in the fluid would be consistent with MS, whereas viruses or bacteria would indicate meningitis.

Talking with a brain specialist as soon as you notice symptoms can lead to a faster diagnosis if you have MS. With advances in treatment of some forms of MS, more people are reducing the long-term complications associated with this autoimmune disease.