Progressive-relapsing multiple sclerosis (PRMS) refers to a pattern of relapses within primary-progressive MS (PPMS). About five percent of MS patients have the progressive-relapsing form of the disease. PRMS is the least prevalent form of MS. Still, it’s important to know the facts about this disease, especially if you have PPMS. This type of MS is known for worsening symptoms that progress over time.

There is more than one type of MS. Johns Hopkins Medicine estimates that up to 15 percent of patients will develop primary-progressive forms. With PPMS, patients immediately experience symptoms that worsen over time. Changes in mobility are the most common symptoms. This can include:

  • changes in gait
  • stiff arms and legs
  • heavy legs
  • inability to walk for long distances

PPMS transitions to progressive-relapsing when a person with PPMS experiences relapses. Relapses are not included in a PPMS diagnosis. If you experience a relapse, your doctor may change your diagnosis to PRMS.

In MS, a relapse often refers to an attack. At the start of the disease, some patients go through fluctuations in symptoms. Sometimes they don’t show any signs of MS for days or weeks at a time. But during dormant periods, symptoms can appear without warning. This is called a relapse.

Relapses in PRMS are different from other forms of the disease. The symptoms of primary progressive MS are consistent and already worse than other forms of multiple sclerosis. A relapse in this stage means an exacerbation of symptoms that are already occurring. Also, there is no noticeable break from the symptoms. Once PRMS develops, relapses can occur spontaneously, with or without treatment.

Mobility symptoms are among the most common signs of PRMS, but the severity and types of symptoms can vary between patients. Other common signs of PRMS can include:

  • muscle spasms
  • weak muscles
  • decreased bladder function (incontinence)
  • dizziness
  • chronic pain
  • vision changes

As the disease progresses, PRMS can cause less common symptoms like:

  • changes in speech
  • tremors
  • hearing loss

Aside from relapses, PRMS is marked by a consistent progression of decreased neurological function. Doctors can’t predict the exact rate of PRMS progression. In many cases, the progression is a slow but steady process that spans several years. The worst cases of PRMS are marked by rapid progression.

PRMS can be difficult to diagnose at first. This is partially because relapses in PPMS are not as noticeable in other less severe forms of MS. Some patients pass off the relapses as having bad days rather than exacerbations of the disease. PRMS is diagnosed with the help of:

  • lab tests, such as blood work
  • magnetic resonance imaging (MRI) scans
  • neurological exams
  • a patient’s medical history detailing symptomatic changes

Once a doctor changes your diagnosis from PPMS to PRMS, your treatment plan will change. Your treatment will focus on helping to manage relapses. The only FDA-approved medications for PRMS are:

  • interferon beta 1-a (Avonex, Rebif)
  • interferon beta 1-b (Betaseron, Extavia)
  • mitoxanthrone (Novanthrone)
  • natalizumab (Tysabri)

Medications are just one aspect of PRMS treatment. Your doctor may also recommend lifestyle changes to help ease your symptoms and improve quality of life. Regular physical activity and nutrition can complement medical care for MS.

There is currently no cure for MS. Like other forms of the disease, treatments may help slow the progression of PRMS. Treatment can also alleviate symptoms. Early medical intervention can help prevent the disease from significantly affecting your quality of life. PRMS is easier to detect because of the severe symptoms, compared with relapsing-remitting MS (RRMS). But it’s important to get a proper diagnosis from your doctor to make sure you receive adequate care.

Researchers continue to study MS to understand the nature of the disease and possibly look for cures. PRMS clinical studies are less prevalent than other forms of the disease because it isn’t as easy to detect. The recruiting process for clinical trials can be difficult given the rarity of this type of MS. Most trials for PRMS study medications to manage symptoms. If you’re interested in participating in a clinical trial, discuss the details with your doctor.