Marfan's syndrome

Question 1

Inheritance?

Answer 1

Autosomal dominant

Question 2

Cause?

Answer 2

It is caused by a defect in the FBN1 gene on chromosome 15 that codes for the protein fibrillin-1.

Question 3

Features?

Answer 3

• tall stature with arm span to height ratio > 1.05
• high-arched palate
• arachnodactyly
• pectus excavatum
• pes planus
• scoliosis of > 20 degrees
• heart: dilation of the aortic sinuses (seen in 90%) which may lead to aortic aneurysm, aortic dissection, aortic regurgitation, mitral valve prolapse (75%),
• lungs: repeated pneumothoraces
• eyes: upwards lens dislocation (superotemporal ectopia lentis), blue sclera, myopia
• dural ectasia (ballooning of the dural sac at the lumbosacral level)

Question 4

Average life expectancy for these patients?

Answer 4

40-50 years

Question 5

What monitoring and treatment has improved life expectancy amongst patients?

Answer 5

Regular echocardiography monitoring and beta-blocker/ACE-inhibitor therapy.

Question 6

Leading cause of death?

Answer 6

Aortic dissection and other cardiovascular problems