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Marfan Syndrome


The Manual's Editorial Staff

Reviewed/Revised Sep 2023
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What is Marfan syndrome?

Marfan syndrome is a disorder that affects the body's connective tissue. Connective tissue is the muscles, tendons, cartilage, and other parts that hold your bones, joints, organs, and tissues together. In Marfan syndrome, the connective tissue is weaker than normal so it stretches, bulges, or tears. Marfan syndrome can cause problems affecting the eyes, heart, and lungs.

Marfan syndrome runs in families.

  • People with Marfan syndrome tend to be very tall and thin

  • Marfan syndrome can be mild or severe

  • People with Marfan sydrome may have eye, heart, and lung problems

  • The most serious complication of Marfan syndrome is a problem with the aorta (the largest artery in the body)

  • Years ago, people with Marfan syndrome had a short life expectancy, but now most people with Marfan syndrome live into their 70s

  • Doctors can’t cure Marfan syndrome, but they can treat some of the symptoms

What causes Marfan syndrome?

Marfan syndrome is caused by an abnormal gene that comes from one parent.

The gene affects the way the body makes a certain protein. Normally, this protein helps build strong connective tissue. In people with Marfan syndrome, connective tissue is weak.

What are the symptoms of Marfan syndrome?

The symptoms of Marfan syndrome can be mild or severe. Many people with Marfan syndrome don't have any symptoms. Some don't have symptoms as children but develop symptoms as adults.

People with Marfan syndrome may have:

  • Unusual tallness

  • Long, thin fingers and long arms, with an arm span that's greater than their height

  • A sternum (breastbone) that’s unusually shaped and pushes out or in more than usual

  • Loose joints

  • Flat feet

  • Knees that bend backward

  • A spine that curves abnormally forward in the upper back (kyphoscoliosis)

They may also have heart, lung, and eye problems such as:

How can doctors tell if I have Marfan syndrome?

If doctors suspect you have Marfan syndrome, they'll ask about your symptoms and if your family has a history of Marfan syndrome. They'll do a physical exam and:

  • Sometimes, take a sample of blood to test your genes (genetic testing)

If you have Marfan syndrome, doctors will check your heart, bones, and eyes by doing other tests such as:

How do doctors treat Marfan syndrome?

Doctors can’t cure Marfan syndrome. To treat some of the symptoms, they may:

  • Prescribe medicines that can make blood flow more gently and prevent problems with your aorta

  • Have children wear a back brace to treat abnormal curving of the spine (or sometimes do surgery to fix it)

  • Do heart surgery to fix any problems with your aorta or heart valves

  • Do eye surgery to fix any problems of your lenses or retinas

Doctors will check your bones, heart, and eyes each year to treat any complications of Marfan syndrome.

Where can I get more information about Marfan syndrome?

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