Tall, slim and flexible, the patient with Marfan syndrome is easily recognizable. However, this syndrome is still poorly understood.


 

What do people as diverse as US President Abraham Lincoln, General De Gaulle, and Australian singer and Youtubeur Troye Sivan have in common? All three men have Marfan syndrome (or are suspected of having it), a rare genetic disease that affects around 12,000 people in France, or one in 5,000. Still too little known, this pathology is not well diagnosed. "Patients and even some doctors do not know the disease", explains Prof. Guillaume Jondeau, cardiologist and coordinator of the Marfan referral center at Bichat hospital (AP-HP, Paris), "and there may be diagnostic wandering" . However, without proper management, the syndrome can be fatal.

The large size, a relative thinness, long and thin fingers, and flexibility of the joints are all distinctive signs to identify a patient with Marfan syndrome. Small tests can put the chip in the patient's or doctor's ear: if the thumb sticks out while it is flat on the palm and the fingers folded over, or if it is possible to go around his wrist, enclosing it with the thumb and little finger. The disease affects the heart, eyes and skeleton as well. Injuries that can result in myopia, displacement of the lens, scoliosis, overlapping teeth, flat feet, etc. These manifestations can vary greatly from person to person, even between siblings. 



Why are they so heterogeneous? Marfan syndrome originates from a mutation in the gene responsible for the production of fibrillin 1, a protein found in all organs. Because of this mutation, too little protein is produced. However, fibrillin ensures the cohesion of tissues: without it, they are more elastic, more flexible than they should be.

Risk of internal bleeding


The most serious, and potentially the most watched, damage is to the heart. Patients with Marfan syndrome have an increased risk of developing a dissection (rupture) of the aorta, the most important artery in the human body that receives blood from the heart and carries it to organs. The heart, working like a pump, forcefully pumps blood into the aorta in spurts. Under the action of this mechanism, the wall of the artery weakens over the years: it widens and becomes thinner. She relaxes. This is a natural but accelerated phenomenon in patient Marfan, whose aortic wall is particularly elastic. When the diameter of the artery exceeds 50 millimeters (this is called dilation of the aorta), the risk of dissection is at its greatest. Left unchecked, blood may seep through the artery wall and create a bruise. For the patient, it is a life-threatening emergency: the wall of the aorta can rupture at any time and allow blood to escape into the body.

Faced with this significant risk of internal bleeding, a woman with Marfan syndrome should be particularly monitored if she wishes to become pregnant, "because there is an increased risk of aortic dissections during pregnancy," explains Professor Jondeau. "It is considered that if the aorta is dilated, it is better to have an operation before pregnancy." Vaginal birth is possible when the aorta is not too dilated, otherwise cesarean section is preferred.

For children, Marfan syndrome can complicate everyday life at school: "Some may have difficulty writing due to the hyperlaxity of their fingers. And many sports are prohibited for the Marfans. We must avoid violent sports and brutal efforts such as rugby or basketball, ”he continues. In addition, the satchels are often too heavy and a special arrangement is needed, ”explains the cardiologist.

A life expectancy close to normal 

Fortunately, screening for Marfan syndrome has radically changed the management of patients and improved their quality of life. The risk of aortic dissection is now limited thanks to preventive treatment with beta blockers, which slow the heartbeat and relieve pressure on the wall of the aorta. And surgical techniques to treat aortic dissection have also advanced. As for the other symptoms, they are taken care of on a case-by-case basis. Patients have gained about 30 years of life expectancy, explains the cardiologist: “In the past, there was 50% mortality by the age of 40. Now the lifespan is approaching that of the unreached population and keeps improving. "