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Marfan Syndrome

(Marfan's Syndrome)


Frank Pessler

, MD, PhD, Hannover, Germany

Last full review/revision Oct 2020| Content last modified Oct 2020
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Marfan syndrome is a rare hereditary disorder of connective tissue, resulting in abnormalities of the eyes, bones, heart, blood vessels, lungs, and central nervous system.

  • This syndrome is caused by mutations in the gene that codes for a protein called fibrillin.

  • Typical symptoms can range from mild to severe and include long arms and fingers, flexible joints, and heart and lung problems.

  • The diagnosis is based on symptoms and family history.

  • Most people with this syndrome live into their 70s.

  • There is no cure for Marfan syndrome or any way to correct the abnormalities in the connective tissue.

Marfan syndrome is caused by mutations in the gene that codes for a protein called fibrillin. Fibrillin helps connective tissue maintain its strength (connective tissue is the tough, often fibrous tissue that binds the body's structures together and provides support and elasticity). If the fibrillin gene is mutated, some fibers and other parts of connective tissue (the tough, often fibrous tissue that binds the body's structures together and provides support and elasticity) undergo changes that ultimately weaken the tissue. The weakening affects bones and joints as well as internal structures, such as the heart, blood vessels, eyes, lungs, and central nervous system (the brain and spinal cord). Weakened tissues stretch, distort, and can even tear. For example, the aorta (the main artery of the body) may weaken, bulge, or tear. Weak tissues in a heart valve can cause the valve to leak. Connective tissues that join structures may weaken or break, separating formerly attached structures. For example, the eye’s lens or retina may separate from its normal attachments.

Symptoms of Marfan Syndrome

Symptoms of Marfan syndrome can range from mild to severe. Many people with Marfan syndrome never notice symptoms. In some people, symptoms may not become apparent until adulthood.

Musculoskeletal problems

People with Marfan syndrome are taller than expected for their age and family. Their arm span (the distance between fingertips when the arms are outstretched) is greater than their height. Their fingers are long and thin. Often, the breastbone (sternum) is deformed and pushed outward or inward. The joints may be very flexible. Flat feet, a deformity of the knee joint that causes the knee to bend backward, and a humpback with an abnormal curve of the spine (kyphoscoliosis) are common, as are hernias. Usually, the person has little fat under the skin. The roof of the mouth is often high.

Heart problems

The most dangerous complications develop in the heart and lungs. Weakness may develop in the connective tissue of the wall of the aorta. The weakened wall may result in blood seeping between the inner layers of the aorta’s wall (aortic dissection), which causes a tear, or in a bulge (aneurysm) that can rupture. These problems sometimes develop before a child is 10 years old.

Pregnancy increases the risk of aortic dissection. Caesarean delivery (C-section) is often recommended to minimize the risk.

If the aorta gradually widens or dilates, the aortic valve, which leads from the heart into the aorta, may begin to leak (called aortic regurgitation). Widening of the aorta occurs in 50% of children and in 60 to 80% of adults. The mitral valve, which is located between the left atrium and ventricle, may leak (mitral regurgitation) or bulge backward into the left atrium (mitral valve prolapse).

These heart valve abnormalities can impair the heart’s ability to pump blood. Abnormal heart valves can also develop serious infections (infective endocarditis).

Lung problems

Air-filled sacs (cysts) may develop in the lungs. The cysts may rupture, bringing air into the space that surrounds the lungs (pneumothorax). These disorders can cause pain and shortness of breath.

Eye problems

The lens of one or both eyes may be displaced (dislocated). People are very nearsighted (unable to see distant objects clearly). The light-sensitive area at the back of the eye (retina) may detach from the rest of the eye (see Detachment of the Retina). Displacement of the lens and detachment of the retina may cause permanent loss of vision.

Spinal cord problems

The sac that surrounds the spinal cord may widen (called dural ectasia). Dural ectasia is common and most frequently occurs in the lower portions of the spine. It may cause headache, lower back pain, or other neurologic problems such as bowel or bladder weakness.

Diagnosis of Marfan Syndrome

  • A doctor's evaluation

  • Genetic testing

  • Echocardiography

  • Magnetic resonance imaging (MRI)

  • X-rays

  • Eye examinations

Doctors may suspect the diagnosis of Marfan syndrome if an unusually tall, thin person has any of the characteristic symptoms or if Marfan syndrome has been recognized in other family members (first-degree relatives such as the father, mother, or a sibling). Doctors also base the diagnosis on specific criteria regarding the extent to which certain organ systems, such as the heart, eyes, and bones, are affected.

Doctors may do an analysis of genes, usually from a sample of blood, to help diagnose Marfan syndrome.

Doctors monitor for complications that can cause serious symptoms. People should have their heart, bones, and eyes checked every year to see if they are getting worse. This annual evaluation usually includes echocardiography of the heart and aorta; x-rays of the hand, spine, pelvis, chest, foot, and skull; and an eye examination. MRI can also be done to evaluate heart and brain problems. Echocardiography and eye examinations are also done whenever symptoms develop.

Prognosis of Marfan Syndrome

Years ago, most people with Marfan syndrome died in their 40s. Today, people who have Marfan syndrome have nearly the same life expectancy as people who do not have this condition. Prevention of aortic dissection and rupture probably explains why the life span has been lengthened.

Treatment of Marfan Syndrome

  • Beta-blockers

  • Sometimes surgical repair of the aorta and valves

  • Sometimes a brace and sometimes surgical repair for curving of the spine

There is no cure for Marfan syndrome or any way to correct the abnormalities in the connective tissue.

Treatment of Marfan syndrome is aimed at preventing and/or fixing abnormalities before dangerous complications develop. Beta-blockers (such as atenolol and propranolol) are drugs that slow the heart rate and decrease the force of heart contractions. These drugs are given to make blood flow more gently through the aorta. However, if the aorta has widened or developed an aneurysm, the affected section can be repaired or replaced surgically. Severe valve regurgitation is also surgically repaired. Pregnant women are at especially high risk of complications with their aorta, so repair of the aorta before conception should be discussed. Angiotensin II receptor blockers (such as losartan and candesartan) also may be given to lower blood pressure.

A displaced lens or retina can usually be reattached surgically.

A brace is used to treat abnormal curving of the spine (scoliosis) for as long as possible. However, some children need a surgical procedure to correct the curve.

People should receive genetic counseling. People and their families may obtain additional information from the National Marfan Foundation.

More Information about Marfan Syndrome

The following is an English-language resource that may be useful. Please note that THE MANUAL is not responsible for the content of this resource.

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