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 degenerative muscle 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 that muscle cells can store or use for energy. But with Pompe, the glycogen continues to build up and causes muscle damage. Pompe is progressive, which means it can get worse over time. There are two types:

Infantile-onset, or IOPD

IOPD presents within the first year of life. Signs and symptoms can include an enlarged heart, motor delays, difficulty breathing, and failure to thrive.

Late-onset, or LOPD

LOPD can present at any age and commonly affects the major muscle groups used in breathing and walking. Eventually, people living with LOPD may need assistance walking or devices to help with breathing.

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. Changes to genes—called variants—can affect how well they work. 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. When 2 carriers for Pompe have children together, there’s a chance their child will inherit the disease or become a carrier.

Early diagnosis can lead to earlier disease management. That's why it's recommended that close family members of someone with Pompe get tested.

How to find out if it’s Pompe disease

How Pompe can be passed down

Click on each parent to change their GAA genes
and see the effect it may have.

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 and could be mild or more severe. However, some of the more common symptoms are:

  • muscle weakness
  • difficulty walking
  • swaying or “waddling”
    when walking
  • difficulty breathing
  • having a harder time
  • 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, 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.

That’s why it’s important to talk to your doctor about all of your symptoms so they can get a complete picture.


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How to test for Pompe disease

Pompe disease is rare, affecting about 1 in 40,000 people, so it’s not the first thing people or their doctors 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

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