MARFAN SYNDROME

Marfan syndrome is a condition in which your body's connective tissue is abnormal. Connective tissue helps support all parts of your body. It also helps control how your body grows and develops.

Marfan syndrome most often affects the connective tissue of the heart and blood vessels, eyes, bones, lungs, and covering of the spinal cord. Because the condition affects many parts of the body, it can cause many complications. Sometimes the complications are life threatening.

People with Marfan syndrome are usually tall and thin with disproportionately long arms, legs, fingers and toes. Marfan syndrome is caused by a dominant gene, which means one of your parents also has the gene and passed it to you.
What causes Marfan Syndrome

Marfan syndrome is caused by a defect in the gene on chromosome 15 that determines the structure of fibrillin, a protein that is a major component of elastin-associated microfibrils. These microfibrils are found in most connective tissue but are abundant in large blood vessels and the suspensory ligaments of the lens. Hence the most prominent features of Marfan syndrome are cardiovascular (heart) and ocular (eye) abnormalities.

Marfan syndrome is inherited in an autosomal dominant manner, which means that if one parent is affected with Marfan syndrome there is a 50% chance that each child will be affected. There are cases where neither parent is affected but they produce a child with Marfan’s syndrome. This de novo or spontaneous mutation occurs in 1 in 4 of all cases of Marfan syndrome.

Marfan syndrome is estimated to affect about 1 in 10,000 individuals.

What are the symptoms of Marfan syndrome?

Marfan syndrome affects different people in different ways. Some people have only mild symptoms, while others are more severely affected. In most cases, the symptoms progress as the person ages. The body systems most often affected by Marfan syndrome are:

• Skeleton - People with Marfan syndrome are typically very tall, slender, and loose-jointed. Because Marfan syndrome affects the long bones of the skeleton, a person's arms, legs, fingers, and toes may be disproportionately long in relation to the rest of the body. A person with Marfan syndrome often has a long, narrow face, and the roof of the mouth may be arched, causing the teeth to be crowded. Other skeletal problems include a sternum (breastbone) that is either protruding or indented, curvature of the spine (scoliosis), and flat feet.
• Eyes - More than half of all people with Marfan syndrome experience dislocation of one or both lenses of the eye. The lens may be slightly higher or lower than normal, and may be shifted off to one side. The dislocation may be minimal, or it may be pronounced and obvious. One serious complication that may occur with this disorder is retinal detachment. Many people with Marfan syndrome are also nearsighted(myopic), and some can develop early glaucoma (high pressure within the eye) or cataracts (the eye's lens loses its clearness).
  
• Heart and blood vessels (cardiovascular system) - Most people with Marfan syndrome have problems associated with the heart and blood vessels. Because of faulty connective tissue, the wall of the aorta (the large artery that carries blood from the heart to the rest of the body) may be weakened and stretch, a process called aortic dilatation. Aortic dilatation increases the risk that the aorta will tear (aortic dissection) or rupture, causing serious heart problems or sometimes sudden death. Sometimes, defects in heart valves can also cause problems. In some cases, certain valves may leak, creating a "heart murmur," which a doctor can hear with a stethoscope. Small leaks may not result in any symptoms, but larger ones may cause shortness of breath, fatigue, and palpitations (a very fast or irregular heart rate).
  
• Nervous system - The brain and spinal cord are surrounded by fluid contained by a membrane called the dura, which is composed of connective tissue. As someone with Marfan syndrome gets older, the dura often weakens and stretches, then begins to weigh on the vertebrae in the lower spine and wear away the bone surrounding the spinal cord. This is called dural ectasia. These changes may cause only mild discomfort; or they may lead to radiated pain in the abdomen; or to pain, numbness, or weakness in the legs.
  
• Skin - Many people with Marfan syndrome develop stretch marks on their skin, even without any weight change. These stretch marks can occur at any age and pose no health risk. However, people with Marfan syndrome are also at increased risk for developing an abdominal or inguinal hernia, in which a bulge develops that contains part of the intestines.
  
• Lungs - Although connective tissue problems make the tiny air sacs within the lungs less elastic, people with Marfan syndrome generally do not experience noticeable problems with their lungs. If, however, these tiny air sacs become stretched or swollen, the risk of lung collapse may increase. Rarely, people with Marfan syndrome may have sleep-related breathing disorders such as snoring, or sleep apnea (which is characterized by brief periods when breathing stops).

How is Marfan syndrome diagnosed?

 An evaluation for Marfan syndrome generally includes:

• A complete physical examination.
• An eye examination by an ophthalmologist (eye doctor). The ophthalmologist uses eye drops to fully dilate the pupils of the eyes and examines them with a slit-lamp (a microscope with a light attached) to look for lens dislocation.
• Heart tests, including an electrocardiogram (EKG) and an echocardiogram. An EKG measures electrical activity in the heart. An echocardiogram is a noninvasive ultrasound that lets doctors look for involvement of the heart and blood vessels. Imaging tests, such as a computed tomography (CT scan) or magnetic resonance imaging (MRI), may be used to check the condition of the aorta.
• A family history to determine if there are other family members known or suspected to have Marfan syndrome and/or who died early due to an unexplained heart disorder or an aneurysm. An aneurysm is a bulging of a blood vessel, such as the aorta, that sometimes can cause the vessel to rupture.
• Genetic testing of a blood sample to help confirm the diagnosis.
• An MRI of the lower spine to look for dural ectasia.

Treatment

There is no specific treatment for Marfan syndrome. A cardiologist, ophthalmologist and orthopaedic surgeon should review patients with Marfan syndrome regularly. Early identification and intervention of risk factors, such as aortic dilation, should prevent or delay complications. With early diagnosis and preventative management a person with Marfan syndrome should expect to have similar life expectancy to that of the average person.

While there is no cure, there are effective treatments, and most people with the disorder live full active lives.

Conventional treatment recommendations include such things as:

1. Ocular and cardiovascular surveillance of all people with Marfan syndrome every 6-12 months
2. Activity restrictions:
NO Isometric exercise (no weight lifting)
No sudden acceleration/deceleration activities (roller coasters, bungy jumping, drag racing)
No unpressurized flights; No SCUBA diving
No competitive sports
No contact sports
3. Medications to minimize the rate of aortic root dilatation (beta blocking agents, calcium channel blocking agents)
4. Adherence to prophylactic antibiotic recommendations as indicated

Close surveillance of the Marfan aorta is recommended during pregnancy. If aortic enlargement is detected in the early stages of pregnancy, aortic imaging studies are recommended every 1 to 3 months until delivery.

CONCLUSION

Recent advances in Marfan syndrome treatment have prolonged the life expectancy of patients considerably. Changes in how the syndrome is treated, including medication, surgical interventions, and monitoring for complications of the syndrome (eg, aneurysms), are all responsible for the increase in life expectancy.