How is multiple sclerosis (MS) diagnosed?

MS is a complex disease that can present and evolve differently. Diagnosing MS is not always straightforward, as there’s no single symptom, physical finding or blood test to confirm if a person has MS. What’s more, some of the early signs or symptoms of MS can be caused by other conditions.

If you’ve not been feeling like yourself or are worried you’ve been experiencing MS symptoms, help is available. Health professionals can provide answers, support and guide you before, during and after a diagnosis.

Whether you have MS or not, reaching out to an MS nurse or your GP (general practitioner) to investigate your concerns is always the right decision for your health. They will listen to your story, take a detailed history of your symptoms and undertake physical and neurological exams. You may then be referred to a neurologist for further tests so you can get an accurate diagnosis.

There’s no single formula or test to diagnose MS, as it can look different in everyone. There can be many reasons your body is showing symptoms of MS. However, there are two key criteria that are used as a basic rule to diagnose MS.

There are a variety of tests to determine if you have MS. Read on to discover some of the methods used to reach a diagnosis.

Magnetic Resonance Imaging (MRI)

MRIs are a medical imaging scan used to detect damage or scarring (i.e., lesions) caused by MS in the central nervous system, which is made up of the brain, optic nerves and spinal cord.

An MS diagnosis may not rely solely on an MRI result, as it’s possible for it to detect:

• lesions caused by another disease
• lesions in healthy people with no ongoing disease.

Sometimes, your medical history and results of other clinical testing can point to having MS. Your MRI results are one piece of the puzzle to create a clear MS diagnosis. Read more about MRIs and MS.

Clinical examination

During a clinical exam, a doctor will examine you for a range of symptoms, including:

• movement and strength
• vision
• balance and coordination
• functions of the five senses (eyesight, taste, hearing, smell, and touch)
• muscle tone and reflexes
• sensation
• memory and thinking.
  

Your medical history is also taken into consideration.

Other diagnostic tests

In many cases, an MRI scan and clinical exams will be enough to diagnose MS. If results are unclear, additional tests may be needed. This can include:

• electrical diagnostic studies – which can show if there’s a slowing of messages in the various parts of the brain
• cerebrospinal fluid studies – which test for a clear fluid that protects your brain and spine. Having multiple oligoclonal bands (proteins) is a sign of inflammation in the central nervous system, which could be caused by MS or another disease
• blood tests – which can be used to rule out other causes for symptoms you’re experiencing.

This page has been reviewed and approved by Executive Manager Client Engagement and Wellbeing Jodi Haartsen. Jodi is a registered MS Nurse who has helped thousands of patients over her 20 years’ experience at Eastern Health MS service in Australia, in several roles including nurse educator, research nurse and nurse practitioner. Jodi is the 2022 winner of the global MS Brain Health Leader Award in the Independent Healthcare Professionals category.