Patient explanation

Gold standard case presentation

Diagnosis and Clinical signs:

This patient has Marfan syndrome, as evidenced by a positive echocardiogram demonstrating aortic root dilatation and mitral valve prolapse. Clinically, he is of tall stature; has an arm span that is wider than he is tall; arachnodactyly in his fingers and toes; a high arched palate and hyper-extension in his hands and wrist. He has a positive family history and a personal history of a pneumothorax and hernia. I would like to arrange baseline blood tests, slit-lamp testing to check for lens dislocation, genetic testing and refer him to Cardiology for further assessment of his valve and aortic abnormalities for possible future surgery.

Discussion

Clinical features

Marfan’s syndrome is an autosomal dominant genetic disorder of the connective tissue caused by mutation in the Fibrillin-1 (FBN1) gene that encodes for a glycoprotein Fibrillin. This patient does not have all of the clinical features, which is not uncommon, as it is a spectrum. We are unable to demonstrate it here, but he also has mild lens dislocation, detected upon slit lamp examination. In 2010, the formal diagnostic criteria, the Ghent Nosology was revised, you can read more here. This patient scores 8 (with ≥ 7 considered a positive systemic score):

• Wrist and thumb sign
• Plain flat foot
• Spontaneous pneumothorax
• Facial features (long face, high arched palate and lens dislocation on slit lamp)
• Mitral valve prolapse

The 2010 Ghent nosology is divided into whether there is a positive or negative family history. If there is a negative family history:

• Aortic root dilatation Z score ≥ 2 AND ectopia lentis
• Aortic root dilatation Z score ≥ 2 AND gene (FBN1) positive
• Aortic root dilatation Z score ≥ 2 AND score ≥ 7
• Ectopia lentis AND gene (FBN1) positive AND aortic root dilatation

If there is a positive family history:

• Ectopia lentis AND positive family history
• Score ≥ 7 AND positive family history
• Aortic root dilatation Z score ≥ 2 (> 20-years) or ≥ 3 (< 20-years) AND positive family history

Organ involvement in Marfan’s syndrome

Musculoskeletal:

• Disproportionately long limbs (including the fingers and toes) with a decreased upper-to-lower body segment ratio
• High arched palate
• Kyphoscoliosis
• Pectus excavatum or pectus carinatum
• Striae of the skin
• Herniae of the femoral or inguinal regions
• Reduced subcutaneous fat

Ocular (often mild and sometimes only detectable under slit lamp examination)

• Ectopia lentis
• Iridodonesis (iris tremor

Cardiac

• Coarctation of the aorta or dilation of the aortic root which leads to aortic regurgitation (with associated collapsing pulse)
• Aneurysm or dissection of the aorta
• Mitral valve prolapse

Respiratory

• Spontaneous pneumothorax
• Bronchiectasis
• Aspergilloma
• Bullae

Management

Conservative: ensuring patient education and support is key along with lifestyle advice. For more information, please visit the Marfan Foundation which has a wealth of resources.

Medical

Cardiovascular – beta-blockers are used to retard the aortic fibre degeneration that leads to progressive aortic root dilatation and subsequent aortic valve incompetence and dissection. Ocular – regular ophthalmological assessment to monitor for retinal detachment and myopia is required. Skeletal: arthritis and myalgia are common problems associated with increased laxity of the joints. Avoidance of heavy stress inducing exercise as well as contact sports can help reduce this. Respiratory: if pectus excavatum exists, then there can be subsequent restrictive lung defects and so this must be monitored for. Sports such as scuba diving must be avoided due to the risks of spontaneous pneumothorax.

Surgical:

Cardiothoracic surgery for aortic root dilatation and valve replacement may be required, based upon the size (> 5.5cm for the aortic root).

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