Marfan Syndrome

Marfan syndrome (MFS) is a genetic disorder of the connective tissue, in particularly affecting the heart, blood vessels, skeleton and eyes. Connective tissue provides the structural support and helps to maintain the elasticity of the ligaments, skeletal structures, blood vessel walls and the heart valves.

How common is MFS?

It is estimated that one in 5,000 to 10,000 people are born with MFS. Occurrences of MFS can occur in all races and affect both genders equally.

What are the features of MFS?

While MFS may be present at birth, some symptoms develop gradually over a number of years. The severity of symptoms varies from person to person, even among affected family members.

The main features include:

• Cardiovascular (heart and blood vessels). Weakening and stretching of the blood vessels can occur. This applies in particular to the aorta (the main blood vessel carrying blood away from the heart) and increases the risk of aortic aneurysm, dissection or rupture (bursting).
  
  The heart’s valves may also be affected. The most common condition is mitral valve prolapse (MVP). In MVP, the valve leaflets become floppy and do not close tightly. This can cause leakage of blood backwards across the valve. This is known as mitral regurgitation (MR). If mitral regurgitation progresses and is left untreated, it can eventually cause heart failure.

• Lungs. Asthma, emphysema, pneumothorax (collapsed lung)
• Skeleton. Tall and thin with long arms, legs, fingers and toes. Flat feet, protruding or indented chest bone, loose joints, scoliosis and skin stretch marks.
• Eyes. Dislocation of lenses, myopia (shortsightedness), retinal detachment, glaucoma
• A family history of MFS in a parent, sibling or child

When should you/your child seek medical attention?

Seek medical attention if there is:

• Chest pain or breathlessness 
• Sudden blurring of vision
• Joint pain
  

What causes MFS?

MFS is caused by changes in the FBN1 gene located on chromosome 15. Genes are instructions for cells to make proteins in the body. MFS is the result of a change (mutation) in the FBN1 gene.

This gene controls the production of fibrillin-1, which is a very fine fibre that is found in connective tissue. Fibrillin fibres come together to form an elastic mesh which helps to support certain structures in our body, such as blood vessel walls and the lens of the eye.

Fibrillin-1 also regulates the activation of transforming growth factor beta (TGF-β) binding protein, which takes part in the regulation of many different cell functions and affects connective tissues throughout the body.

Everyone carries two copies of each gene, one inherited from each parent. MFS follows a dominant inheritance pattern, which means the presence of one faulty FBN1 gene can cause MFS.

Is MFS inherited?

If either parent has MFS, a child has a 50% chance of inheriting the disease.

Among people with MFS, about 75% of them would have inherited the genetic change from one of their parents. As some people with MFS may have a mild form of the disorder, the parent may not have been previously recognised as having MFS.

The other 25% of people with MFS have it because of a new mutation in the gene.

How is MFS diagnosed?

MFS is diagnosed based on a full evaluation by a doctor familiar with the disorder. This involves the following:

• Thorough physical examination
• Complete family history
• Full eye examination
• Echocardiogram (ultrasound of the heart)
• Genetic testing for a causative mutation in the FBN1 gene can also provide helpful information
• Full eye examination in some cases
  

Can MFS be cured?

While it is not possible to cure MFS, much can be done to make sure you/your child has the best possible outcome.

How is MFS managed?

The multidisciplinary medical team looking after you/your child will be able to address specific medical concerns and routine MFS-related health issues.

Management measures may include:

• Regular echocardiograms to assess the heart and width of the aorta. Medications and/or surgery may be required if the width of the aorta gets too wide.
• Maintaining good dental and skin hygiene, which is important to reduce the risk of infection of the heart valves.
• Antibiotic prophylaxis may be required before surgery and dental procedures in some cases. Please discuss with your doctor for the latest update on antibiotic prophylaxis.
• Careful monitoring of the skeleton to detect problems with the spine or chest bone.
• Regular eye examinations to monitor for myopia and lens dislocations.

There are also important lifestyle considerations for an individual with MFS:

• Ensure a balanced diet, engage in low-intensity exercise and avoid smoking. These measures are also good for general health.
  
• Avoid heavy weight lifting and contact sports. Discuss with your doctor about recommendations for exercise and activities.
  
• With proper management of the cardiovascular manifestations, the life expectancy of someone with MFS approximates that of the general population.
  

• Pregnant women with MFS may be at high risk of obstetric and cardiac complications due to increased stress of the aortic wall especially during delivery. Please consult your doctor for preconception care and counselling.
  

How likely will I have a child with MFS if I have MFS?

If a parent has MFS, the risk of having a child inherit the gene that causes MFS is 50% in every pregnancy.

How likely will I have another child with MFS if neither my spouse nor I have it?

In about 25% of cases, MFS is the result of a spontaneous change (mutation) in the genetic material of the sperm or egg at conception in families with no previous history of the disease.

In such cases, the risk of having another child with MFS is low (< 1%).

MFS is a lifelong condition. Should you require financial assistance or emotional support, please approach your doctor for referral to a medical social worker.

Download the Marfan Syndrome brochure.