Marfan syndrome is a rare genetic disorder caused by the alteration of the gene for a protein called fibrillin 1 (FBN1). It affects connective tissues (a group of tissues that maintains the structure of the body by supporting internal organs and other tissues), causing more or less serious problems in the heart and blood vessels, ligaments, skeleton, eyes and lungs.
Disorders related to the syndrome can occur at any age and vary greatly even within the same family. Some people are affected by the syndrome only mildly while others develop more severe disorders (symptoms).
The spread of the disease is about 1 in 5,000 people affected, with no difference between the sexes.
Typical features of Marfan syndrome include:
- abnormal height
- abnormally long and slender fingers and toes (arachnodactyly)
- heart defects
- dislocation of the lens (the lens of the eye is found in an abnormal position)
Marfan syndrome can affect different parts of the body, including the skeleton, eyes, heart and blood vessels (cardiovascular system).
The severity of the complaints (symptoms) varies greatly, so some people have mild symptoms, others very severe.
However, the ailments tend to get worse as a person gets older.
Regarding their physical structure, people with Marfan syndrome have very particular characteristics, such as:
- very tall stature with long thin arms and legs
- slouchy appearance (they have loose but poorly coordinated movements)
- excessively loose and very flexible joints
- tapered and very long fingers (arachnodactyly)
Other physical characteristics may include:
- small lower jaw
- narrow and high palate
- sunken eyes
- flat feet
- scoliosis (abnormal curvature of the spine)
- sternum that protrudes outward (keeled chest or barrel chest) or inwards (pectus excavatum)
Another disorder (symptom) associated with the syndrome, and which indicates central nervous system involvement, is the "dura mater ectasia, that is to say the enlargement of the lining that surrounds the spinal cord, especially at the level of the lumbo-sacral spine. The ectasia causes some consequences such as headache, back pain, numbness or pain in the legs.
The most common disorder affecting vision is lens displacement (ectopia lentis) that moves from its natural location due to excessive looseness of the ligaments. Other possible disorders include:
- glaucoma, increased pressure in the eyeball which, if left untreated, can cause permanent vision loss
- cataract, formation of cloudy patches in the lens of the eye causing blurred or hazy vision
- retinal detachment, separation of the light-sensitive layer of cells at the back of the eye (retina) from the blood vessels that supply it with oxygen and nutrients
Marfan syndrome can affect the cardiovascular system with particularly serious consequences if it affects the aorta (the body's main artery) and heart valves.
In people with Marfan syndrome, the walls of the aorta are weak, which can sometimes cause progressive dilation (aortic aneurysm) or rupture of the vessel (aortic dissection) resulting in internal bleeding (blood loss).
As for the effects on the heart valves, they consist in the imperfect closure of the mitral and tricuspid valves (which regulate the entry and exit of blood inside the heart between the atrium and the ventricle and cause the flow of blood in the heart to proceed in a " one way) and the resulting reflux of blood (valve insufficiency). The aortic valve can also become incontinent, causing the left ventricle to enlarge. Mitral valve insufficiency can be complicated by arrhythmias, endocarditis or heart failure.
Another disorder present in those with Marfan syndrome are the so-called stretch marks (small pink, red or white stripes on the skin). They form because the skin is not as supple as it should be. In this case, stretch marks are more likely to appear on the shoulders, hips and loins.
Marfan syndrome is a rare disease with autosomal dominant inheritance: there is a 50% chance that the child of a parent with Marfan syndrome will inherit the syndrome. In 25% of cases, however, none of the parents has the syndrome and the fibrillin gene changes (mutates) for the first time in the parent's egg or sperm.
This genetic defect leads to the abnormal production of a protein, called fibrillin, which causes some bones to overgrow, resulting in abnormal lengthening of the limbs. A person with Marfan syndrome, therefore, can be tall because their arms and legs grow. more than normal.
Although in some cases it is quite evident, Marfan syndrome can be difficult to ascertain (diagnose). Typically, the most identifiable signs are:
- tall stature
- legs and arms extended
- tapered and elongated fingers
- ectopia of the lens (due to the excessive elasticity of the ligaments, the lens moves from its natural location)
- ease of dislocation (due to the excessive elasticity of the ligaments of the joints)
- alterations of the spine and palate
In most cases, the assessment (diagnosis) of Marfan syndrome is based on a thorough physical examination and a detailed assessment of the person's and their family's state of health over time.
The doctor usually carries out a medical examination which should include:
- listening to the heart (auscultation)
- skin check to check for stretch marks
- search for any physical characteristics of the syndrome, such as a high palate, the curvature of the spine and long, thin arms and legs
The disease can be particularly difficult to detect in children because most disorders do not usually appear until late childhood and the teenage years. If Marfan syndrome is suspected, the child will need to be closely monitored so that any ailments can be treated as soon as they arise.
Marfan syndrome causes disorders (symptoms) common to various diseases also characterized by connective tissue changes, such as Ehlers-Danlos syndrome or Loeys-Dietz syndrome.
The family doctor may request as additional tests:
- eye examination
- chest x-ray, to highlight abnormalities in the bones and in certain organs, such as the heart and lungs
- magnetic resonance angiography (MRA) with contrast liquid, to make evident the internal structures of the aorta
Genetic tests, usually on a blood sample, can also be done to help determine (diagnose) Marfan syndrome.
There is currently no cure for Marfan syndrome and therapies focus on managing the disorders (symptoms) and reducing the risk of complications.
The use of drugs is essential to alleviate the disorders and avoid any complications, especially those relating to the cardiovascular system. In this case, drugs to reduce blood pressure such as beta blockers are particularly suitable.
Since Marfan syndrome affects different parts of the body, therapy can involve different healthcare professionals:
- geneticist (genetic disorders specialist)
- genetic counselor, which provides information, emotional support and guidance to people diagnosed with a genetic disorder
- orthopedic surgeon
Because Marfan's syndrome can affect almost any part of the body, it can cause a wide variety of complications. The severity of the disorders (symptoms) varies greatly so that some people have mild symptoms, others very severe. however to get worse as a person gets older.
The most serious complications experienced by those with Marfan syndrome involve the heart and blood vessels. The alteration of the connective tissue can weaken the aorta, the large artery that originates from the heart and supplies blood to the body.
More serious complications include:
- aortic aneurysm
- dissection of the aorta
- changes in the heart valves, which could also lead to heart failure
Marfan syndrome can cause changes in the spine, of which scoliosis is the most prominent feature. The abnormal curvature of the spine can cause long-term (chronic) back pain and, in severe cases, even make it difficult to regulate. breathing as the spine can press against the heart and lungs.
Also there spondylolisthesis, that is to say the forward displacement of a vertebra with respect to the one below, is one of the most common disorders in those suffering from this syndrome and can cause back pain and stiffness.
Eye-related complications, which in some cases can even cause permanent vision loss, can include:
- displacement of the lens (ectopia lentis), displacement from their natural location due to excessive looseness of the ligaments. Occurs in more than half of people with Marfan syndrome
- retinal detachment, light-sensitive tissue that lines the back wall of the eye
- early onset glaucoma or cataractsGlaucoma is characterized by an increase in pressure inside the eye which damages the optic nerve. Cataracts are cloudy patches that form in the lens of the eye causing blurred or hazy vision. Glaucoma and cataracts usually appear at a young age.
People with Marfan syndrome should keep fit by exercising regularly and eating a healthy, balanced diet. No significant lifestyle changes are needed.
As for physical activity, they should avoid contact sports such as rugby and other activities such as:
These types of exercise could strain the heart and, by increasing blood pressure and heart rate, increase the risk of a tear in the aorta. These activities also strain the joints. Marfan often have weak joints, the risk of suffering joint damage is increased.
The cardiologist will be able to give further advice on which sports and physical activities are best suited.
Following a healthy lifestyle and adequate drug treatment, the life expectancy of people with Marfan syndrome is now similar to that of the rest of the population.
NHS. Marfan syndrome (English)
Mayo Clinic. Marfan syndrome (English)
Tor Vergata Polyclinic Foundation. Regional Reference Center for Diagnosis and Therapy of Marfan Syndrome. Marfan syndrome. Diagnostic therapeutic assistance pathway (elaborated in December 2012)
Orphanet. Marfan syndrome
Rare Diseases Observatory (OMaR). Marfan syndrome