Multiple Sclerosis

Multiple sclerosis (MS) is an autoimmune condition that affects your brain and spinal cord (central nervous system).

With MS, your immune system mistakenly attacks myelin cells. These are the protective covers (sheaths) that surround brain and spinal cord nerves. Myelin sheath damage interrupts messages (signals) that your nerves send throughout your body to perform functions like vision, sensation and movement.

Myelin damage can occur in your brain, spinal cord and nerves that supply your eyes. There’s no cure for MS, but treatment is available to help minimize ongoing damage from it and help you manage symptoms.

What are the types of multiple sclerosis?

There are four types of multiple sclerosis. You can think of the types as a way for your provider to describe your symptoms, instead of being four different conditions:

• Clinically isolated syndrome (CIS): When you have the first episode of symptoms suggestive of MS, but don’t meet criteria for having MS, healthcare providers often categorize it as CIS. Inflammation and myelin damage cause your symptoms. CIS may develop into multiple sclerosis.
• Relapsing-remitting multiple sclerosis (RRMS): This is the most common way that multiple sclerosis begins — an estimated 85% of people diagnosed with MS have this type. MS causes flare-ups (relapses or attacks) of new or old symptoms. Periods of remission follow (when symptoms stabilize or go away).
• Secondary progressive multiple sclerosis (SPMS): In many cases, RRMS eventually progresses to SPMS. In the secondary progressive stage of multiple sclerosis, nerve damage accumulates and symptoms gradually worsen. You may still experience some relapses or flares, but periods of remission (when symptoms stabilize or go away) are less likely to happen.
• Primary progressive multiple sclerosis (PPMS): In some cases, MS symptoms may start off slowly and gradually worsen over time from the very beginning, without any periods of clear relapses or remission.

Three rare MS variants include:

• Tumefactive multiple sclerosis: A characterization of this variant of MS is the formation of large areas of demyelination in your brain, which may appear similar to tumors. Often, a sample of brain tissue is needed to differentiate this from other issues, like brain cancers.
• Balo’s concentric sclerosis: A characteristic of this variant of MS is lesions with the appearance of concentric rings (in the shape of a target) of myelin damage appearing on an MRI, which gives this condition its name.
• Marburg variant multiple sclerosis: This is a very rare and aggressive form of MS characterized by rapid progression, which may result in death when left untreated.

How common is multiple sclerosis?

Studies show that there are almost 1 million adults in the U.S. living with multiple sclerosis.