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Marfan Syndrome
Marfan syndrome is an autosomal dominant abnormality of connective tissue exhibiting variable penetrance.
The disorder is due to mutation of the fibrillin 1 gene located on 15q21.1.1
The mutation limits the body’s ability to make proteins needed to build connective tissue.1
The gene FBN1 encodes fibrillin-1, a glycoprotein that is the main constituent of the microfibrils of the extracellular matrix.
Reduced or abnormal fibrillin-1 leads to tissue weakness, increased transforming growth factor β signaling, loss of cell–matrix interactions, and, finally, to the different phenotypic manifestations of Marfan syndrome. 1
Marfan syndrome, an autosomal dominant disorder caused by mutations of the fibrillin gene on chromosome 15, is a frequent cause of ectopia lentis.
Patients are tall and thin, with notably long limbs and digits.
An anterior chest deformity known as pectus excavatum is sometimes seen, and vertebral abnormalities include scoliosis and lordosis.
In addition, a highly arched palate and crowding of the teeth may occur.
Cardiovascular complications include mitral valve prolapse and mitral regurgitation.
Cystic medial necrosis can lead to dilation of the aortic root and aortic regurgitation. Life-threatening complications are aortic aneurysm and aortic dissection.
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Fibrillin-1 is the major constituent of extracellular microfibrils and has structural and regulatory functions in the extracellular matrix
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Marfan syndrome phenotype is thought to be the result of structural abnormalities and dysregulation of transforming growth factor β signaling
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Marfan syndrome typically affects cardiovascular, skeletal, ocular, and neural systems and its diagnosis is based on clinical (Ghent) criteria
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Aortic root dilatation in the leading cause of morbidity and mortality in patients with Marfan syndrome
Marfan syndrome has no cure
The type of treatment you receive will depend on what parts of your body are affected and the severity of your condition.
Lens dislocation
Pars plana vitrectomy and primary scleral-fixated IOL implantation gives quick and good visual rehabilitation in adult patients with Marfan's syndrome. The described surgical method is complex and need a prolonged operative time
A 19-year-old college sophomore is referred by his ophthalmologist because of the finding of ectopia lentis (dislocation of the lens), which has resulted in visual difficulties that have interfered with his performance on the varsity basketball team. The patient is very tall, with long limbs and long, slender, spider-like fingers. His chest has a “caved-in” appearance, and he also has a modest degree of scoliosis. A midsystolic “click” is heard, and an echocardiogram reveals mitral valve prolapse. The most likely diagnosis is
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A. Ehlers-Danlos syndrome.
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B. Fabry disease.
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C. Hurler syndrome.
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D. Marfan syndrome.
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E. Pompe disease.
A 25-year-old man presents to his physician because of the recent unexpected death of his brother. His brother died suddenly while playing basketball. His autopsy report said the cause of death was an aortic dissection and also mentioned that he had a myxomatous mitral valve. The patient remembers that his brother was diagnosed with a heart murmur, and that he also has a murmur. He is concerned that he may die suddenly, similar to his brother's death. This patient is at most risk for which one of the following conditions?
Answer
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