Understanding late-onset
Pompe disease

Being informed helps you advocate for yourself or a loved one with Pompe disease.

What is Pompe disease?

Pompe is a rare disease that causes muscle weakness when the body doesn’t have enough of an enzyme called GAA. Normally, this enzyme breaks down a type of sugar called glycogen into glucose that your muscle cells use for energy.

But with Pompe disease the glycogen builds up, gradually damaging and destroying the muscle.

There are two types of Pompe disease—one that starts in infancy and another that can present at any age. This second type is known as late-onset Pompe disease, or LOPD.

Late-onset Pompe disease

It commonly affects the muscles in and close to your core–or torso–including the major muscle groups used in breathing and walking. Late-onset Pompe disease is progressive, which means it can continue to get worse over time, making things that were once easy to do more difficult.

Eventually, people living with late-onset Pompe disease may need assistance walking or devices to help with breathing. The challenges this creates can be both physical and emotional. That’s why it’s key to talk to your doctor about ways to help manage your disease.

Pompe disease and family genes

Genes are made up of DNA and carry the instructions that tell the body how to grow and function. You inherit 2 copies of every gene, 1 copy from your mother and 1 copy from your father. Each gene has a unique job to do. And changes to genes—which are called variants—can affect how well they do their job. The gene involved with Pompe disease is called the GAA gene.

Someone with 1 variant of the GAA gene is a “carrier” of Pompe disease. Healthy carriers of Pompe disease may pass the Pompe gene variant on to their children. When 2 carriers for Pompe have children together, each one of their children may inherit the disease or become a carrier or be unaffected (not a carrier nor do they have the disease).

If you have Pompe, it’s possible that some of your family members may have it, even if they aren’t showing any signs or symptoms. Or they may be carriers or not affected at all. Pompe disease is progressive, which means it gets worse over time. Early diagnosis can lead to earlier disease management. That’s why it’s recommended that close family members of someone with Pompe get tested for the gene.

How to find out if it’s Pompe disease

How Pompe is inherited

We created this interactive graphic to help visualize how the variant gene for Pompe can be passed down from one generation to the next. Click on each parent icon to change their GAA genes.

Pompe affects males and females equally.

How Pompe is inherited

We created this interactive graphic to help visualize how the variant gene for Pompe can be passed down from one generation to the next. Click on each parent icon to change their GAA genes.

Pompe affects males and females equally.

Unaffected individual
doesn’t have Pompe, and can’t
pass it down
Carrier (no Pompe disease)
has 1 variant, 1 normal,
they can pass down either
Affected individual
has 2 variants and inherits Pompe

Everyone’s experience with Pompe disease is different. It could be mild or more severe or it could progress slowly and the symptoms vary. However, some of the more common symptoms are

  • Muscle weakness
  • Difficulty walking
  • Swaying or “waddling” when walking
  • Difficulty breathing
  • Having a harder time exercising
  • Problems swallowing
  • Fatigue
  • Morning headaches
  • Digestive problems

One of the challenges is that these symptoms can overlap with other conditions and often lead to Pompe disease being misdiagnosed, especially since Pompe disease is so rare. For example, the breathing problems may lead a respiratory specialist to suspect sleep apnea or muscular dystrophy. If muscle weakness and swallowing are an issue, a neurologist may think it’s myopathy or limb-girdle muscular dystrophy. In such situations, Pompe should be one of the diagnoses to consider.

That’s why it’s important to talk to your healthcare provider about all of your symptoms so they can get a complete picture. And advocate for yourself: speak up if you feel something still isn’t quite right. After all, your healthcare provider is a partner in your health and wants you to have the care you truly need.

How to get tested for Pompe disease

Pompe disease is rare, affecting about 1 in 40,000 people, so it’s not the first thing people or their healthcare providers generally think of or look for. It can take time to get a definitive diagnosis. The following tests can help determine if it’s Pompe:

  • Genetic test showing abnormalities in the GAA gene
  • Blood test or biopsy showing decreased GAA enzyme

Finding out that you have Pompe disease can bring out a range of emotions. Everything from fear and anxiety about what happens next and what the future will look like to relief—if you’ve spent years being misdiagnosed and struggling to find out what’s really wrong. And many of these emotions can happen at the same time. But you don’t have to go through it alone or sit there reeling with unanswered questions.

CareConnectPSS® has helped many newly diagnosed people navigate this difficult time with the depth of their experience and the warmth of people who have been dedicated to the Pompe community for more than a decade.