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Multiple sclerosis (MS) can present different symptoms in different people at different times and the process of diagnosis can be a lengthy one for some.

Some symptoms such as mobility changes are more obvious, but some are not, for example, fatigue or sensory disturbances. There is no set pattern and some people will experience symptoms that others will not and these can also vary from time to time, occurring singly or in combination.

Some people have mild symptoms, while others have problems that are moderate or severe, taking the form of episodes or ‘relapses’ (a temporary worsening of symptoms). Other people experience a slow, sometimes almost imperceptible change in their physical condition with no obvious episodes.

Unfortunately there is no one single test or procedure that can be used to diagnose MS. It is often a case of watching and waiting to see if new symptoms appear or previous symptoms recur. This process can be frustrating; it is hard to accept that a conclusive diagnosis can take months, or years.

Diagnosis is based on a number of things such as looking into medical history, neurological examinations and a series of tests. Other conditions need to be ruled out before a diagnosis can be confirmed.

First steps to diagnosis

In October 2014, the National Institute of Health and Care Excellence (NICE) issued new guidelines (1) for the management of multiple sclerosis, including guidelines for the steps medical advisors, such as GPs and neurologists, should take to reach (or exclude) a diagnosis of MS.

NICE states that the most common symptoms or ‘clinical presentations’ a person would visit their GP with are:

  • Loss or reduction in vision in one eye, with painful eye movements
  • Double vision
  • Ascending sensory disturbance or weakness (a change in sensation or strength that moves up the body)
  • Balance problems or clumsiness
  • Altered sensation travelled down the back when bending the neck forward called Lhermitte’s Syndrome, this can feel like a finger being run down the spine, or a tingling feeling

NICE also suggests that, to be recognised as a symptom of MS, these should last over 24 hours and may have persisted over several weeks or months.

If you are experiencing symptoms, it is important to make an appointment with your GP to discuss them. It might be helpful for you to use the ‘Symptom Diary’ that is available below.

A GP will perform a number of blood tests to exclude alternative diagnoses, before referring you to a neurologist if MS is suspected.

NICE recommends a GP carry out the following blood tests before such a referral is made, although not all may be performed:

  • A full blood count
  • Inflammatory marker test
  • Liver function tests
  • Renal function tests
  • Thyroid function tests
  • Calcium
  • Glucose
  • Vitamin B12
  • HIV serology test

It is worth noting that many other conditions may and do produce symptoms almost indistinguishable from MS symptoms.

Visit our 'Is it MS?' web page for more information 

Being referred to a neurologist

Only a neurologist can make the diagnosis of MS. A neurologist will perform other tests to ensure that symptoms are consistent with an inflammatory process in the body and that all other alternative diagnoses have been excluded.

The process starts with a neurological examination during which your full medical history will be taken into account. Collecting your history is important as prior symptoms such as visual disturbances or numbness may have been treated or passed by without the consideration of MS at the time. The neurologist will then perform simple tests to check movement, coordination, balance, reflexes and other sensory tests. The neurologist performs these tests to establish whether there are signs of the inflammatory process in the body.

If your medical history and neurological examination suggest MS, more tests will be conducted to look for further evidence in your body. The neurologist will be looking for ‘lesions’ on the brain or spinal cord. These lesions occur when the inflammation process has left scarring on the fatty myelin sheath that surrounds the nerve. A neurologist will need to establish that lesions have developed at different times, and in different areas of the body for a diagnosis of MS.

The neurologist will make a diagnosis of MS based on established criteria, such as the revised 2010 McDonald criteria (2). The McDonald Criteria are used to seek to establish evidence of damage to the central nervous system (CNS) comprising of the brain and spinal cord. The McDonald criteria is available to download below. In summary, a diagnosis of MS is undertaken through a combination of your medical history, clinical and neurological assessment and judgment by a neurologist.

The McDonald Criteria


MRI scanning

A Magnetic Resonance Imaging scan (MRI) is used to identify any areas of the brain or spinal cord that may have scarring. An MRI scanner consists of a large doughnut-shaped magnet with a tunnel in the centre which along with radio waves is used to take pictures of the brain or spine. You will be placed on a table that slides into the tunnel. It is a painless procedure, although quite noisy.

The MRI test can last between 20 to 40 minutes. It can feel a little claustrophobic but headphones are provided and you can contact the MRI’s operator at any time.

Sometimes a dye called gadolinium is used to enhance the image. The dye is injected into a vein before the MRI starts. The dye can assist the neurologist to determine what is a new or ‘active’ lesion, and what are older areas of scarring.

NICE states that MS cannot be diagnosed on the basis of the MRI findings alone and other tests are needed, including the initial neurological examination.

Lumbar Puncture

A lumbar puncture is a procedure where a small sample of cerebrospinal fluid (CSF) is taken and analysed for any abnormalities that can indicate MS. CSF is the fluid that surrounds and protects the brain and spinal cord.

This procedure is done by first injecting a local anaesthetic into the lower back and then inserting a needle between the lower discs of the spine to draw off the CSF. This procedure may be performed as either an inpatient or a day patient in a hospital. You need to be in a hospital environment due to the need to monitor your health and rest will be needed for several hours after the procedure to allow your body to recover.

Evoked Potentials

These are very simple electrical tests that measure the time it takes for your nerves to respond to stimulation. Visual Evoked Potentials (VEP) are most commonly used in the diagnostic process. A conducting gel and electrodes are applied to the scalp. For VEPs, the electrodes are applied to the rear (occipital region) of the scalp over the brain areas that register visual stimuli. The stimuli for VEP are delivered by a strobe light or a screen with a checkerboard pattern. The electrodes measure the time it takes for the eye to see the image and the nerve impulse to reach the occipital region of the brain.

It is important to keep in mind that these tests do not always give a conclusive result. Mostly people with MS will show some lesions or areas of inflammation on a MRI but there are still a small proportion of people whose MRI shows nothing at all. As with a lumbar puncture, there is a minor percentage of people with MS who will have a negative result.

Here is a list of questions you could ask your health professional about multiple sclerosis, including questions about medication and treatment options.

Questions to ask your health professional (PDF document)

Questions to ask your health professional (Word document)

Choices booklets and useful resources

Diagnosis (PDF Choices booklet)

Diagnosis (Word Choices booklet)

Is it MS? (Web page version)

Is it MS? (PDF Choices booklet)

Is it MS? (Word Choices booklet)

Sympom diary (PDF document)

Symptom diary (Word document)

Am I having a relapse? form (PDF document)

Am I having a relapse? form (Word document)

Newly diagnosed?

Download a copy of our newly diagnosed booklet or order a printed copy using our form

Newly diagnosed booklet