Marfan syndrome is a medical condition that affects the entire body, specifically the body’s connective tissue. Connective tissue is the “glue” that supports and binds other tissues of the body. It is found in many parts of the body including the joints, eyes, heart, blood vessels, lungs, bones and in the membrane covering the brain and spinal cord.
Marfan syndrome can affect both men and women of any race or ethnic group. It is estimated that 1 in 5,000 people have Marfan syndrome. The majority of affected individuals inherit the condition from one of their parents; however, some people are the first in their family to have Marfan syndrome. A person with Marfan syndrome has a 50% chance to pass the syndrome on to their children. The genetic test for Marfan syndrome is available at most medical centers.
What Causes Marfan Syndrome?
Marfan syndrome is caused by a genetic change (mutation) that affects the production of a protein that is a key part of the connective tissue. The abnormal gene is the FBN1 gene on chromosome 15 that encodes for the protein fibrillin-1. In patients with Marfan syndrome, the change in the FBN1 gene causes the cells in the body to either produce too little fibrillin or to produce abnormal fibrillin. As a result, the connective tissue is not properly formed, leading to the changes or symptoms associated with Marfan syndrome.
Normally, microfibrils work like a scaffold. They support larger fibers. These in turn provide strength to connective tissues that make up bones, blood vessels, lungs, the lens of the eye and other parts of the body.
In Marfan syndrome microfibrils do not properly form, weakening the connective tissue that supports many organs in the body.
How Is Marfan Syndrome Diagnosed?
Marfan syndrome is diagnosed by using criteria that have been established by physicians who specialize in this disorder. Diagnosis may be made using clinical features and confirmed with genetic testing. Guidelines for diagnosis are based on clinical features seen on physical exams, as well as information obtained from the family history, echocardiogram, eye exam and/or genetic testing.
Your physician may recommend genetic testing to help diagnose Marfan syndrome. Genetic testing consists of obtaining a blood sample from your child to examine the DNA for the abnormal gene mutation that causes Marfan syndrome.
What Are the Symptoms of Marfan Syndrome?
Many children with Marfan syndrome do not complain of any symptoms. However, children who have eye involvement may complain of having difficulty seeing objects that are far away or have blurry vision. Other symptoms may include back or joint pain.
Physical Signs & Effects of Marfan Syndrome
People with Marfan syndrome often have a tall, thin body build with long arms, legs, fingers and toes. They may have flat feet, or fallen arches, and may have an inward rotation (pronation) of their feet. Many affected individuals have curvature of the spine (scoliosis), an indentation of their chest (pectus excavatum), or a protrusion of the chest (pectus carinatum). The roof of the mouth (palate) is usually high and narrow with crowding of the teeth. The lower jaw may recede, making it appear as though the child has an overbite. The face may be long, narrow and flat.
The lens of the eye is responsible for focusing vision on objects. The lens is held in place by tiny muscles. In people with Marfan syndrome, these tiny muscles may be more “stretchy” than normal, which allows the lens to move out of place from the center of the eye. This process is called lens dislocation (ectopia lentis) and is fairly common in people with Marfan syndrome. It can be hard to diagnose lens dislocation by just looking at the eye, therefore eye doctors (ophthalmologists) must dilate the pupil and examine the eye with a special instrument to see if the lens is out of place.
People with Marfan syndrome are also more likely to develop cloudiness within the lens of the eye (cataract) and tend to do so at earlier ages than normally expected. They are also at risk for developing tears or holes in the retina (retinal detachment).
A retinal detachment is a medical emergency and needs to be treated as soon as possible. Prompt treatment can prevent permanent damage to the eye such as partial or complete blindness. Symptoms of a retinal detachment include sudden appearance of “floaters” in the eye, flashes of light or a shadow appearing over part of the vision. To reduce the risk of a retinal detachment, people with Marfan syndrome should avoid high impact activities such as boxing, football and diving.
The Heart & Aorta
Connective tissue is present in the heart muscle, valves and blood vessels, including the aorta. Approximately 75% of patients with Marfan syndrome have changes in the heart’s mitral valve (prolapse). In patients with mitral valve prolapse, the valve can leak, allowing blood to flow backward. Patients with Marfan syndrome should always be followed by a cardiologist, especially if changes in their aorta have been found.
The aorta is the largest blood vessel in the body and may be affected by Marfan syndrome. The aorta is made up of three separate layers: the intima, media and the adventitia. The middle layer (media) is elastic and is the layer that is affected most by Marfan syndrome, making it weaker than a normal aorta.
Every time the heart beats, there is pressure or stress that occurs on the aortic wall. Over years, this stress or pressure causes the aorta to stretch (dilate) and eventually form an aortic aneurysm. If an aneurysm forms, there is an increased risk of an aortic dissection (tear), which is a life-threatening medical emergency.
Note: Symptoms of an aortic dissection include chest pain radiating (spreading out) to the neck or back, difficulty breathing, dizziness or lightheadedness and passing out. If this happens, call 911 immediately, as this is a life-threatening emergency.
Patients with Marfan syndrome are at risk for developing collapse of the lung (pneumothorax). This can occur spontaneously or from blunt trauma to the chest. Symptoms of pneumothorax include difficulty breathing and chest pain.
The Nervous System
The central nervous system is made up of the brain and the spinal cord, which are surrounded by a membrane called the dura. Cerebrospinal fluid is contained within the dura and bathes the brain and spinal cord. The dura is also made of connective tissue, and therefore, can stretch over time. As it expands, the dura can press on the vertebrae of the spine. This most commonly occurs at the bottom of the spine and can result in pain, headaches and numbness in the legs.
Other Body Systems
There is an increased incidence of hernias in the groin (inguinal hernias) in people with Marfan syndrome. It may also take a longer time for cuts or skin wounds to heal.
How Is Marfan Syndrome Treated?
People with Marfan syndrome should be followed by healthcare providers familiar with the condition and its effect on all body systems. Frequently this is done by a specialized team of providers from cardiology, ophthalmology, orthopaedics and genetics. Additional specialists may also be asked to participate in care as needed. At a minimum, patients should be seen on a yearly basis, unless more frequent follow-up is recommended.
There is no cure for Marfan syndrome at this time. However, medications are used to help slow the progression of the aortic dilation. Several types of medications can be used, which include beta blockers, angiotensin receptor blockers (ARBs) and angiotensin converting enzyme (ACE) inhibitors. In addition, strenuous exercise, weight lifting, competitive sports and contact sports may be restricted. If valve abnormalities are found, antibiotics may be prescribed around the time of surgical or dental procedures to prevent infections within the heart (endocarditis).
What Are the Long-term Effects of Marfan Syndrome?
The life expectancy for someone with Marfan syndrome is similar to someone in the general population, as long as they receive frequent surveillance and appropriate medical care. Medical and surgical treatments continue to improve, offering patients improved quality of life.
In general, women with Marfan syndrome can become pregnant safely. However, they should be under the care of a cardiologist as well as an obstetrician/gynecologist who is experienced in the care of patients with this connective tissue disorder. If possible, it is best to talk to your doctors before becoming pregnant so that careful planning can be done. If either parent is affected by Marfan syndrome, there is a 50% chance that the child will have Marfan syndrome. Because of variability in the expression of the Marfan gene, it is impossible to predict how severely a child will be affected.