MS or Not? Conditions That Mimic It & When to Get a 2nd Opinion

MS or Something Else? Conditions That Mimic Multiple Sclerosis (and When to Get a Second Opinion in LA)

Multiple Sclerosis (MS) is a condition where your immune system attacks the protective coating around your nerves. This damages your brain and spinal cord, causing symptoms like vision problems, numbness, trouble walking, and thinking issues.

MS is often misdiagnosed

Up to 1 in 5 people diagnosed with MS actually have something else. That's why getting the right diagnosis is so important.

Getting the right diagnosis is crucial. If you're diagnosed with MS, you'll likely start medications that you might take for years. You don't want to take these powerful drugs if you don't actually have MS.

Why Is MS Hard to Diagnose

Why are mistakes common? MS shares symptoms with many other conditions. It also shows up as white spots on brain scans (MRIs) that can look like other problems.

There's no single "MS test" that gives a clear yes or no answer. Doctors need to evaluate all the evidence before confirming MS.

In fact, one study found that only 11% of patients referred to specialists based on abnormal MRIs actually had MS. Just having spots on your brain scan doesn't automatically mean you have MS.

To diagnose MS accurately, doctors use a specific set of guidelines called the "McDonald Criteria". These criteria require evidence of damage in at least two separate areas of the central nervous system (brain, spinal cord, or optic nerves), occurring at different times. Evidence can come from your symptoms, neurological exam findings, MRI scans, spinal fluid tests, and other tests that measure how quickly electrical signals travel through your nerves.

The criteria have been updated several times as medical knowledge has improved, most recently in 2024. MS specialists are familiar with applying these criteria correctly, which helps prevent misdiagnosis.

Time matters in MS diagnosis

Getting an accurate MS diagnosis quickly is important. The sooner proper treatment begins, the better the long-term outcomes for MS patients. But rushing to a diagnosis without proper testing can lead to mistakes.

Let's look at conditions that can be mistaken for MS and when you might want a second opinion.

Common Conditions That Look Like MS

Since MS can cause so many different symptoms, other health problems can look similar. These "MS mimics" can cause similar symptoms or even create spots on MRI scans that resemble MS.

Important fact

Before diagnosing MS, doctors must first rule out many other possibilities - from infections to vitamin deficiencies.

1. Migraine Headaches

Migraines aren't just bad headaches. They can cause visual disturbances, numbness, tingling, and other neurological symptoms.

People with MS get migraines more often than others. Some migraine sufferers develop small white spots on their brain scans that can be mistaken for MS.

How doctors tell the difference:

Migraine Symptoms	MS Symptoms
Last minutes to hours	Last days to weeks
Often cause extra sensations (like flashing lights, tingling)	Often involve loss of function (vision loss with eye pain, numbness)
MRI spots are smaller, round and in deep brain areas	MRI spots are ovoid and affect more specific locations

Did you know?

Migraine is one of the most common conditions misdiagnosed as MS. In one study, 22% of people misdiagnosed with MS actually had migraines.

2. Lupus

Lupus is an autoimmune disease that can affect many parts of your body - joints, skin, blood cells, kidneys, and nerves. It's sometimes called "the great imitator" because it can look like many other diseases, including MS.

Lupus patients might have extreme fatigue, brain fog, or numbness - all symptoms that overlap with MS. Lupus can also cause brain inflammation that shows up on MRI scans similar to MS.

The difference is that lupus usually causes additional symptoms like joint pain, specific rashes (like a butterfly-shaped rash on the face), sunlight sensitivity, or kidney problems. These aren't typical MS symptoms.

Blood tests can help here. People with lupus almost always have high levels of specific antibodies in their blood that people with MS don't have.

The problem with symptom overlap

When symptoms like fatigue, numbness, and brain fog occur, many conditions could be responsible. Always work with specialists who consider all possibilities before settling on a diagnosis.

3. Neuromyelitis Optica (NMO)

NMO involves immune attacks on the optic nerves and spinal cord, causing eye pain, vision loss, and spinal cord inflammation. These attacks can look very similar to MS flare-ups.

Key differences:

NMO spinal cord lesions are usually longer than MS lesions
NMO often doesn't affect the brain as much early on
A specific blood test can detect antibodies found in NMO but not MS

Getting the right diagnosis is critical because some MS medications can actually make NMO worse.

4. MOG Antibody Disease (MOGAD)

MOG antibody disease, also called MOGAD, is another condition that can look very similar to MS. Like NMO, it's an autoimmune condition that targets a specific protein in your nerves called myelin oligodendrocyte glycoprotein (MOG).

People with MOGAD can experience:

Vision problems and eye pain (optic neuritis)
Spinal cord inflammation
Brain inflammation
Seizures in some cases

What makes MOGAD different from MS:

MOGAD often causes more severe optic neuritis (eye inflammation)
MRI findings in MOGAD typically show different patterns than MS
A specific blood test can detect MOG antibodies that aren't present in MS
MOGAD symptoms often respond differently to steroids than MS symptoms

This condition was only recently discovered as a distinct disease, so some patients previously diagnosed with MS might actually have MOGAD. The good news is that many people with MOGAD have a single attack and recover well, though others can have recurring episodes.

Like with NMO, getting the correct diagnosis is important because certain MS treatments might not work well for MOGAD, and different treatment approaches may be needed.

Recent medical advances

MOGAD was only recognized as a distinct disease in the last decade. Medical understanding of these conditions is constantly evolving, which is why seeing specialists who stay current with the latest research is so important.

5. Vitamin B12 Deficiency

A simple vitamin deficiency can sometimes cause symptoms that look like MS. Vitamin B12 is essential for healthy nerves. Low B12 levels can cause:

Numbness and tingling in hands and feet
Weakness
Balance problems
Thinking difficulties

In severe B12 deficiency, the spinal cord can be damaged in a way that mimics MS. B12 deficiency can also cause fatigue and mood changes.

Testing B12 levels is a standard part of MS evaluation. The good news is that if B12 deficiency is found, treatment with supplements can often reverse the symptoms if caught early.

6. Small Vessel Disease

This involves chronic changes in the brain's tiny blood vessels due to aging, high blood pressure, high cholesterol, smoking or diabetes. Even normal aging can lead to small spots on brain scans.

Many people over age 50 will have a few white spots on an MRI due to normal wear-and-tear. These can look similar to MS spots.

The difference is in the pattern. Small vessel disease spots are usually in different locations than typical MS spots and don't change over time the way MS spots do.

Aging and brain scans

Over 50% of people over age 60 will have some white spots on brain MRIs that have nothing to do with MS. Don't panic if your scan shows some spots - context and pattern matter more than just their presence.

7. Lyme Disease

Lyme disease comes from tick bites and causes a distinctive bull's-eye rash in most cases. If not caught early, it can affect the nervous system, causing:

Numbness
Weakness
Facial drooping
Thinking difficulties
Spinal cord inflammation

Lyme can even cause white spots on brain scans in some cases.

The key differences are that Lyme is more common in certain regions (Northeast U.S. and Upper Midwest), often causes fever and joint pain, and can be confirmed with blood tests. Lyme is treated with antibiotics, while MS requires completely different treatments.

Travel history matters

While Lyme disease is less common in Southern California than in the Northeast, LA residents who travel or have lived in high-risk areas should mention this to their doctor when neurological symptoms appear.

8. Fibromyalgia

Fibromyalgia causes widespread pain, fatigue, and sleep problems. It shares several symptoms with MS:

Chronic fatigue
Brain fog (difficulty concentrating)
Headaches
Numbness or tingling sensations

The big difference is that fibromyalgia doesn't cause actual nerve damage. MRI scans in fibromyalgia patients are usually normal, and neurological exams don't show the specific problems that MS would cause.

Sometimes patients can have both conditions. Treatment approaches are very different - fibromyalgia is managed with exercise, sleep strategies, and nerve pain medications rather than MS treatments.

9. Other Conditions to Rule Out

There are many other conditions that can mimic MS:

Other autoimmune disorders: Sjögren's syndrome, sarcoidosis, and blood vessel inflammation can all look like MS.
Stroke and vascular problems: Small strokes or mini-strokes can sometimes be confused with MS if they cause temporary symptoms.
Spinal problems: A pinched nerve or bulging disc in the neck can cause numbness, weakness, or bladder issues similar to MS.
Infections: Besides Lyme, other infections like syphilis, HIV, and HTLV-1 can sometimes cause symptoms that look like MS.
Functional disorders: Sometimes very real neurological symptoms occur without visible damage on tests. This is called functional neurological disorder (FND) and can be confused with MS.

This is why a thorough evaluation is so important for anyone with suspected MS. An MS specialist will know what to look for and what tests to order to tell these conditions apart.

When to Get a Second Opinion for MS

It's completely normal and often recommended to seek a second opinion about an MS diagnosis. Here's when you should consider it:

Limited testing was done: If your diagnosis was based just on an MRI or a quick exam, without more thorough testing, consider a second opinion. MS diagnosis shouldn't rely on just one test.
Your symptoms aren't typical: If your doctor mentioned your case doesn't look like typical MS, another expert opinion might help.
Treatments aren't working: If you're on MS treatment but not improving or getting worse in unusual ways, your diagnosis might need another look.
Before starting strong medications: MS treatments can have significant side effects. If you have any doubts, get a second opinion before starting long-term therapy.
For peace of mind: MS is a major diagnosis - it's natural to want confirmation from more than one expert.
To see an MS specialist: If your diagnosis came from a general neurologist, seeing a doctor who specializes in MS can be very helpful. They have the most up-to-date knowledge about MS.

Getting a second (or even third) opinion is normal with any serious medical condition. It's your health, and you deserve to be confident in your diagnosis and treatment plan.

Next Steps: Getting Clarity on Your MS Diagnosis in Los Angeles

Facing a possible MS diagnosis can feel overwhelming, but you don't have to figure it out alone. Expert help is available.

If you're in Los Angeles or Southern California, consider scheduling a consultation with our MS specialists at Achilles Neurology Clinic. We provide comprehensive MS evaluations and welcome second opinions for MS.

Our goal is to ensure your diagnosis is correct and that you feel confident in your treatment plan. Early and accurate diagnosis leads to the best outcomes, no matter what condition you have.

Contact our Los Angeles MS Clinic to book an appointment. We'll thoroughly review your history, perform detailed exams, check necessary scans or labs, and discuss our findings with you in plain language. We combine expert knowledge with compassionate care so you never feel like "just another patient."

What to bring to your appointment

When seeking a second opinion, bring all your previous MRI scan images (not just the reports), complete medical records, a list of all medications tried, and a symptom diary noting when problems occur and what triggers them.

Living with unexplained symptoms or an uncertain diagnosis is stressful. Take control by getting clarity. Schedule your consultation today.

Get Clarity on Your MS Diagnosis

Schedule an appointment with our MS specialist at the Achilles Neurology Clinic. Whether you need a thorough evaluation or a second opinion, we'll help you understand your symptoms and ensure an accurate diagnosis. Take the next step toward clarity and confidence in your care.

Learn More About MS

Our comprehensive guide to understanding multiple sclerosis covers everything from early warning signs and diagnostic tests to treatment options and lifestyle management. Learn what to expect in patient-friendly language.

MS or Something Else? Conditions That Mimic Multiple Sclerosis and When to Get a Second Opinion in LA