Abstract
This paper will discuss the etiology and pathology of Marfan syndrome. It will also explore the signs and symptoms of the genetic disorder. Finally, it will discuss some of the available treatments, quality of life and prognosis of some one affected by Marfan syndrome.
Marfan Syndrome: A Brief Overview Marfan syndrome was first described in 1896 by a French pediatrician by the name of Antoine Marfan (1858-1942). Marfan syndrome is a genetic disorder that affects the connective tissue in the body. The three main body systems that Marfan syndrome attacks are they eyes, bones and muscles, and the cardiovascular system. Marfan syndrome is also known as arachnodactyly in Greek and translates to “spider-like fingers” because of the elongated bones in the hands and fingers. Marfan syndrome is caused by a mutation on chromosome 15 that affects the production of fibrillin. Fibrillin is a protein that is responsible for allowing tissues to stretch repeatedly with out weakening. With this fibrillin defect, people with Marfan syndrome have hypermobility in their joints causing them to become weak and very loose. Another characteristic of Marfan syndrome is that some patients have excessively long limbs with an arm span greater than their height. The external affects of Marfan syndrome very greatly even with patients in the same family. The severity of Marfan syndrome is different from person to person. According to Rebecca J. Frey’s journal on Marfan, “Between 15% and 25% of cases result from spontaneous mutations. Mutations of the fibrillin gene (FBNI) are unique to each family affected by Marfan, which makes rapid genetic diagnosis impossible, given present technology.” (Frey, 2005) Due to the huge range of effects that Marfan has, it is difficult to diagnose. Currently there is no objective test for Marfan. Marfan also does not show up in tissue samples and has no effect on blood or body fluids. In order to diagnose Marfan syndrome, a series of tests are needed that look at the main areas that are affected, as well as obtaining an accurate family history. The signs and symptoms of Marfan very greatly from individual to individual and will usually get worse with time. Some of the more sever issues that Marfan syndrome can cause are with the major blood vessels and heart. With the connective tissue being so loose, it causes the mitral valve in the heart to not seal correctly causing a mitral valve prolapse. A mitral valve prolapse can cause heart arrhythmias and has been linked to sudden death. Marfan also causes issues in the connective tissues in the major blood vessels such as the aorta. It will cause the aorta to enlarge and may lead to an aortic dissection. The enlarged aorta may also cause aortic regurgitation. Aortic regurgitation is when some of the blood when pumped out of the heart is leaked back in to the heart. This may result in an enlarged heart and eventually heart failure. According to Frey, approximately 90% of the people affected by Marfan will develop some sort of cardiac complication. (Frey, 2005) Some other signs and symptoms of Marfan involve the bone structure of the body. In the spine, there are signs of scoliosis and kyphosis. Scoliosis is indicated by a curvature of the spine while kyphosis, also known as hunchback, will be indicated by the outward bowing of the spine. Patients my also experience a swelling of the Dura membrane surrounding the brain and spinal cord resulting in dural ectasia. Some other bone disorders seen in patients with Marfan are seen in the feet. Because of the loose connective tissue in the feet they are unable to hold up to the weight of the individual causing them to develop pes planus (flat feet). In the chest and sternum patients will have pectus excavatum or pectus carinatum. Pectus excavatum is a condition where the sternum will be sunken inward. This can cause difficulty breathing and in sever cases it may interfere with the function of the heart. Pectus carinatum is where the sternum protrudes outward. Pectus carinatum usually will not cause issues with breathing. It is also possible for the patient to have both conditions at the same time. Patients with Marfan may also develop problems with their eyesight. Some of the eye issues include: Cataracts, nearsightedness, glaucoma and are more susceptible to retinal detachment. According to Frey, 65% to 75% of the patients with Marfan syndrome will have ectopia lentis (dislocation of the lens of the eye). “This condition is an important indication for diagnosis of the syndrome because there are relatively few other disorder that produce it.” (Frey, 2005) The effects of Marfan differ greatly from patient to patient. Some are barely affected while others are debilitated from the disorder. The treatments for Marfan are tailored to the specific disorders of the patient. Generally there are a lot of prophylactic treatments to ensure that the blood pressure is low as to not put stress on the aorta. There are regular tests done to insure that the aorta is within normal limits and is not in danger of dissecting. Some patients that have severe issues with scoliosis may undergo surgery to straiten the spine. Children that are diagnosed with Marfan are tested regularly for the signs of scoliosis. If it is caught in time the use of a brace usually with correct the issue. There are also surgical procedures to correct pectus excavatum and pectus carinatum. The surgical procedure for pectus carinatum is to correct the appearance of the deformity. Treatment for the bone deformities in the foot are usually treated with special orthotic inserts and surgery is rarely needed. Patients with Marfan also have to have regular eye exams because they are more susceptible to complications with glaucoma and cataracts. They should also be checked with a slit lamp to insure that there have been no dislocations of the lens of the eye. Patients with Marfan are also advised to avoid activities that cause jarring to the body or head because of the possibility of rental detachment. Patients that exhibit more of external signs of Marfan syndrome may have more quality of life issues. Patients may need to seek counseling to help them deal with the physical effects and appearance of the disorder. Marfan is an autosomal dominant disorder and some one who has it has a 50% chance of passing it along to their children. The choice to have children would be a difficult one that may require genetic counseling. Due to the recent advances in surgical techniques and medical treatments, the prognosis for a patient with Marfan syndrome had greatly increased. According to Frey, “As of 1995, the life expectancy of people with the syndrome had increased to 72 years; up from 48 years in 1972.” (Frey, 2005) Early diagnosis of Marfan syndrome is imperative.
References:
Frey, R. J. (2005). Marfan Syndrome. In B. Narins (Ed.), The Gale Encyclopedia of Genetic Disorders (2nd ed., Vol. 2, pp. 782-788). Detroit: Gale. Retrieved from http://go.galegroup.com.proxy.itt-tech.edu/ps/i.do?id=GALE%7CCX3451500264&v=2.1&u=itted&it=r&p=GVRL.Health1106&sw=w&asid=c116dd62213ef01b3eb4eee62011cf41
