Multiple sclerosis (MS) is an inflammatory disease in which the immune system attacks the central nervous system, damaging the myelin, the protective covering around certain nerves.

Over the last 20 years, multiple sclerosis has become a highly manageable disease. While there is no cure, new therapies can lessen the effects of MS and improve your quality of life, according to Mount Sinai’s Corinne Goldsmith Dickinson Center for Multiple Sclerosis.

In this Q&A, Ilana Katz Sand, MD, the Center’s Associate Director and Professor of Neurology at the Icahn School of Medicine at Mount Sinai, explains why it can be difficult to diagnose MS and what you can do if you are misdiagnosed.

How is multiple sclerosis diagnosed?

Unfortunately, there is no single diagnostic test for MS. Rather, an MS diagnosis is made by considering all available data and appropriately applying the diagnostic criteria. Clinicians review a patient’s medical history and symptoms, perform a neurological examination, and use magnetic resonance imaging, or MRI, to make a non-invasive scan of the brain and spinal cord. They will sometimes recommend a lumbar puncture (spinal tap) for additional information.

Other testing, such as examining the optic nerves, and blood tests to appropriately rule out other conditions, may also be performed. Any potential “red flags” to an MS diagnosis must be considered and the diagnostic criteria must then be carefully applied.

What are some overlapping symptoms between MS and other conditions?

What can sometimes make the diagnostic process difficult is that symptoms of MS can overlap with those of other conditions. For example, optic neuritis, an inflammation of the optic nerve that can cause pain and vision loss, is a common presenting symptom of MS. It is also a common presenting symptom of other inflammatory conditions such as neuromyelitis optica spectrum disorder and myelin oligodendrocyte glycoprotein antibody disorder.

These conditions are also associated with lesions in the brain and spinal cord like MS. Other symptoms that are common in MS, such as fatigue and cognitive fogginess, are common in many other illnesses and are not specific to MS. Clinicians need to use clues from the way the symptoms present, the pattern of lesions on the MRI scan, blood and spinal fluid testing, and sometimes additional diagnostic tests to help differentiate MS from other conditions when it is not initially clear.

How common is it to misdiagnose MS?

Misdiagnosis of MS is not that uncommon. Research suggests that among referrals to medical centers that specialize in multiple sclerosis and offer advanced care, the rate of MS misdiagnosis may be as high as 20 percent. This is consistent with my personal experience over the years.

In my experience, misdiagnosis most commonly occurs when the clinician has not considered a diagnostic “red flag” carefully enough or has inappropriately applied the MS diagnostic criteria when a patient’s history, exam, or MRI findings are not typical for MS.

A change in clinical impression can also occur when new technology becomes available that causes the clinician to see things a different way. However, the numbers we see in research studies do not necessarily mean that one in five people who currently have an MS diagnosis have been misdiagnosed. Patients who are referred to advanced care centers tend to be more challenging cases, so this likely introduces some bias into this figure. The rate of misdiagnosis in the overall population is probably lower.

What should someone do if they have been misdiagnosed with MS but are still experiencing symptoms?

For someone who previously received an MS diagnosis but has since been told the diagnosis was not correct, the most important action is to understand why the clinician has changed their impression.

The next steps will be different depending on whether a new lab test result became available, clinical symptoms have changed (for example, there has been a lack of expected response to treatment), or the MRI scan has evolved in a way that was different than anticipated.

The clinical reasoning should drive next steps for further evaluation of the patient’s ongoing symptoms. The other action item I recommend is focusing on symptom management, taking a holistic view of care that incorporates optimizing things like nutrition, exercise and physical activity, and mental health. Attention to these parts of care can make a really big difference in the way a person feels regardless of their diagnosis.

You may have heard about chronic traumatic encephalopathy (CTE), a brain disease linked to repeated hits to the head. CTE has been found in some former NFL players and others who had repeated head impacts.

If you or a family member played contact sports, you may wonder about the risk of CTE. The risk depends in part on how often and for how long a person experienced repeated head impacts. Even people with extensive exposure do not always develop CTE.

In this Q&A, Kristen Dams-O’Connor, PhD, Director of the Brain Injury Research Center of Mount Sinai, explains what researchers know about CTE, what may affect your risk, and what you can do if you are concerned.

Kristen Dams-O’Connor, PhD

How do I know if I’m at risk for CTE?

The biggest known risk factor for CTE is extensive exposure to repeated hits to the head over a long period of time. Researchers call these repetitive head impacts.

American football is the best-studied example. Repeated head impacts can also happen in other contact sports, including soccer, and possibly during military service or from domestic violence.

In football, the risk appears to increase based on how many years a person played, the level at which they played, and their position. For example, someone who played football briefly as a child or teenager would have a very different level of exposure than an NFL player who experienced repeated impacts for many years. If someone played in a position that exposed them to more impact, like a lineman, that may also carry greater risk.

Just because someone experiences repetitive head impacts does not mean they will get CTE. In fact, most people who have played football never develop CTE, and it isn’t clear yet why some do but others don’t.

Can one concussion cause CTE?

Current evidence does not suggest that one traumatic brain injury, whether it’s a mild concussion or more severe traumatic brain injury, puts you at significant risk for CTE. Researchers have found very few cases of CTE in people whose only known exposure was a single traumatic brain injury. The concern is greater when a person has repeated head impacts over time. These impacts do not have to cause diagnosed concussions, it is the extent and duration of repetitive head impacts that seems to matter most.

Can I be tested for CTE?

There is currently no test that can definitively diagnose CTE while a person is alive. CTE can only be diagnosed by examining brain tissue under a microscope after death.

Researchers are studying ways to diagnose CTE during life. These include blood tests that may detect signs of disease and specialized brain imaging. These tools are still being studied and cannot currently diagnose CTE in patients.

What symptoms should I be concerned about?

People who were found to have CTE after death have experienced symptoms such as:

• memory changes
• acting without thinking
• irritability
• trouble controlling emotions
• poor decision-making
• problems with planning, organizing, and completing tasks

Having these symptoms does not mean you have CTE. They are common after traumatic brain injuries and can also occur with dementia and many other conditions. At this time, researchers cannot tell from symptoms alone whether a person has the brain changes associated with CTE.

Substance use, including alcohol and drug use, can also contribute to symptoms during life, and may also contribute to the deaths of some people who are later diagnosed with CTE. But these concerns should not automatically be attributed to CTE, and many can be treated.

What can I do if I’m worried about CTE?

First, do not assume you have CTE. Problems such as memory difficulties, emotional changes, depression, or trouble controlling anger may have other causes, and some can be treated effectively. Also, fearing you have CTE may cause psychological problems. For example, research has found that some people who fear they have CTE experience depression and even suicidal thoughts and behaviors. Instead, focus on getting treatment for the symptoms you are experiencing rather than assuming CTE is causing them.

Behavioral and psychological treatments may help with some symptoms. For example, the Brain Injury Research Center of Mount Sinai offers neuropsychology and brain injury rehabilitation services that can help patients manage problems with thinking, memory, emotions, and behavior. Treatment may include psychotherapy, cognitive rehabilitation, and learning strategies for managing emotions. Medications may also be appropriate for certain symptoms.