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Smoldering multiple sclerosis

A MyMSTeam Member asked a question 💭
Benson, MN
March 8
 · 
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A MyMSTeam Member

Another term for PIRA progression independent of relapse activity

March 10
A MyMSTeam Member

“ Smoldering MS (also spelled smouldering MS in British English), short for smoldering multiple sclerosis, refers to a chronic, low-level, ongoing inflammatory and neurodegenerative process in multiple sclerosis (MS) that continues to cause gradual damage and disability progression—even in the absence of obvious relapses, new lesions on standard MRI scans, or acute inflammatory activity.
This concept has gained prominence in recent MS research as a way to explain why many people with MS experience slow, steady worsening of symptoms (such as fatigue, cognitive changes, mobility issues, or subtle motor/cognitive decline) despite treatments that effectively control relapses and visible inflammation.”

March 10
MyMSTeam

What is smoldering MS?

Smoldering MS refers to a slow-burning process where brain damage continues even during remission when you're not having obvious symptoms. It involves specific brain lesions called "smoldering lesions" (also known as rimmed lesions or chronic active lesions) that remain active for years and keep Show Full Answer

What is smoldering MS?

Smoldering MS refers to a slow-burning process where brain damage continues even during remission when you're not having obvious symptoms. It involves specific brain lesions called "smoldering lesions" (also known as rimmed lesions or chronic active lesions) that remain active for years and keep growing, damaging nerves in those areas.

These lesions have dark boundaries visible on special MRI scans. The dark rims contain iron-rich immune cells that signal ongoing attacks on your nerves, causing continued damage and inflammation even when you feel okay.

How does it differ from regular MS activity?

Unlike relapses where symptoms flare up, smoldering MS causes gradual worsening called "progression independent of relapse activity." This means your disability can progress even when you're not having attacks and no new lesions appear on standard scans.

People with more rimmed lesions tend to experience worse problems with movement and thinking at younger ages, even while on MS treatment. Current treatment options

Current disease-modifying therapies (DMTs) don't directly target smoldering MS lesions because they can't cross the blood-brain barrier. However, some may have indirect effects on smoldering MS.

Promising new treatments called BTK inhibitors are being tested in clinical trials. These tiny molecules can cross the blood-brain barrier and may slow or stop the damage from smoldering MS.

What you can do

Lifestyle factors can affect smoldering MS progression:
* Exercise regularly
* Eat well
* Don't smoke
* Limit alcohol
* Get good sleep
* Review medications with your doctor

Taking care of your overall health helps manage MS better. Talk with your neurologist about smoldering MS and any changes in your symptoms during regular follow-up visits.

March 8

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