Can MS Be Diagnosed Through Blood Tests?

Multiple sclerosis (MS) diagnosis can be tricky because there isn't a specific test for MS and the symptoms can overlap with many other conditions. Instead, the diagnosis is usually based on a combination of your history, imaging scans, and tests to rule out other conditions. Blood tests are frequently part of this process.

This article discusses the role of blood tests in the diagnosis of MS.

Laboratory professionals doing blood tests

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Early Symptoms of MS

As with most autoimmune illnesses, the symptoms of MS and their severity vary from person to person. It's important to note that not everyone with MS will experience the same initial symptoms, and symptoms may vary and cluster together differently.

For many people with MS, visual changes are the first symptom experienced, the most common of which is optic neuritis (ON).

Optic neuritis is the sudden inflammatory demyelination, or myelin damage, of the optic nerve in the eye. Commonly seen in younger females, ON presents as sudden, painful, one-sided vision loss without any other neurological symptoms.

It is usually treated with corticosteroid drugs. People living with ON should be monitored for development of MS.

In addition to optic neuritis, other commonly experienced early symptoms of MS may include:

  • Extreme fatigue
  • Numbness and tingling sensations
  • Weakness
  • Tremors
  • Dizziness
  • Paralysis
  • Bladder and bowel dysfunction
  • Cognitive changes

Another common early symptom of MS is dysesthesia, commonly referred to as the "MS hug." With this symptom, you would feel a squeezing, banding, tightening sensation of the torso, much like a blood pressure cuff which is tightened too much. These associated symptoms often mimic those of a heart or panic attack.

Tests and MS Diagnosis

In 2017, the McDonald Criteria used to determine an MS diagnosis were revised to offer more specific guidance and to avoid misdiagnosis of the disease.

The McDonald Criteria combines information about your symptoms with magnetic resonance imaging (MRI) and cerebrospinal fluid (CSF) findings.

In addition to imaging, neurologic testing, and spinal fluid analysis, lab work and a thorough medical history are also important to help rule in or rule out the diagnosis of MS.

Blood Testing

There is no specific blood test available to determine if a person has MS or not. However, extensive blood work is necessary to help rule out other conditions that can mimic multiple sclerosis.

Diseases which resemble MS and can be ruled out by a thorough history and specific blood tests include, but are not limited to:

In order to correctly diagnose MS, all other possible diagnoses must be ruled out. For this reason, blood testing plays an important role in the proper diagnosis of MS.

Medical History

A thorough medical history combined with a neurologic exam may provide enough information to suspect MS. Your history will provide information and necessary details on possible past "attacks" or symptoms. It also provides information on your birth location and the geographical region where you were raised.

Birth Location May Affect MS Risk

Regions closest to the equator have a low incidence of multiple sclerosis. Studies have also found that people who immigrate from their place of birth take on the level of risk of their new location.


Magnetic resonance imaging (MRI) uses magnetic waves to produce images of various parts of the body. For diagnostic use in MS, MRIs of the brain and spinal cord can provide findings consistent with MS.

MRIs of the brain can demonstrate characteristic white matter lesions, while MRIs of the spinal cord and associated nerves can show myelin damage. After diagnosis, repeat MRIs can help to monitor the progression of MS.

Lumbar Puncture

Cerebrospinal fluid (CSF) surrounds the brain and spinal cord and helps to provide them with adequate nourishment. CSF also filters and helps remove toxins from the brain and other sensitive areas within the CNS. When demyelination occurs, certain types of proteins get released into the CSF and accumulate.

A lumbar puncture, or spinal tap, is a procedure performed to try and extract CSF for analysis. Common CSF findings in people with MS include a high level of oligoclonal bands. Oligoclonal bands indicate an increase in autoimmune activity.

It's important to note that CSF analysis on its own is not enough to make the diagnosis of MS. However, combined with other methods, it can help to confirm a proper diagnosis.

Evoked Potentials

Evoked potentials (EPs) are a type of neurological testing which evaluates how quickly nerve signals can communicate with each other. These tests also measure how large or small of a response the nerve signals may produce.

Since these nerve signals are disrupted in people with MS, the EP findings may be a way to predict disease progression and identify individuals who may be candidates for clinical trials. More research is still needed in this area to truly assess the role of EP testing in the diagnosis of MS.

Next Steps

As with any diagnosis, MS treatment can be tricky. Finding the right regimen may take time. Working with an MS specialist can help tailor treatment to your individual case. Just as symptoms vary from person to person, so do treatment plans.

Additionally, seeking support from local groups or foundations like the National Multiple Sclerosis Society is key to long-term treatment and success.

Disease-modifying therapies (DMTs), physical therapy, good sleep hygiene, and a healthy diet can also help you to manage symptoms.


MS is an autoimmune disease which attacks the body's central nervous system. It leads to symptoms such as visual changes, weakness, fatigue, cognitive impairment, and more. Symptoms vary by individual.

Through a thorough medical history, neurologic examination, specific blood testing, and MRI imaging, providers can diagnose MS and develop effective treatment plans to manage symptoms and prevent future attacks.

There is no specific blood test to diagnose MS directly, but lab work plays a critical role in ruling out other diseases that may mimic MS.

A Word From Verywell

If you or someone you know is experiencing symptoms of MS, contact your healthcare provider as soon as you can. Quick and early diagnosis of MS can lead to a better prognosis. Many MS treatments are available to help you live well with the disease.

Frequently Asked Questions

  • Can you self-diagnose multiple sclerosis?

    MS is a complex disease which can initially present with very vague and generalized symptoms. It's best to keep track of any symptoms you may be experiencing and discuss them promptly with your healthcare provider.

  • At what age is multiple sclerosis usually diagnosed?

    While MS can be diagnosed at any age, it is most commonly diagnosed between the ages of 20 and 50. Most initial cases are diagnosed in a person's 30s.

  • Can you have multiple sclerosis for years without knowing it?

    It is possible to have slow and minimal demyelination occur without symptoms. However, once enough damage is done, or enough nerves are affected, symptoms will occur. It's also possible to have an isolated case of symptoms, followed by years of no symptoms, before the eventual return and progression of the disease. Benign MS, while still controversial in its nature, refers to MS which has remained relatively inactive for years, even decades after initial diagnosis.

5 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. Kale N. Optic neuritis as an early sign of multiple sclerosisEye and Brain. 2016;8:195-202. doi:10.2147/EB.S54131

  2. Johns Hopkins Medicine. Multiple sclerosis.

  3. National Multiple Sclerosis Society. Updated McDonald criteria expected to speed the diagnosis of MS and reduce misdiagnosis.

  4. National Multiple Sclerosis Society. Factors in distribution of MS.

  5. Hardmeier M, Leocani L, Fuhr P. A new role for evoked potentials in MS? Repurposing evoked potentials as biomarkers for clinical trials in MSMult Scler. 2017;23(10):1309-1319 doi:10.1177/1352458517707265

By Katherine Alexis Athanasiou, PA-C
Katherine Alexis Athanasiou is a New York-based certified Physician Assistant with clinical experience in Rheumatology and Family Medicine. She is a lifelong writer with works published in several local newspapers, The Journal of the American Academy of PAs, Health Digest, and more.