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Showing posts with label marfans syndrome. Show all posts
Showing posts with label marfans syndrome. Show all posts

Stigmata of marfan's syndrome

Stigmata of marfan's syndrome are the following
Findings in Hand
  • Positive wrist sign,
  • Positive hand sign
  • Arachnodactyly
  • Upper segment/lower segment ratio < 0.8
  • Arm span—height > 5 cm
Findings in Face
  • High arched palate
  • Dislocated lens
Findings in Chest
  • Pectus excavatum
  • Pectus carmatum
  • Kyphoscoliosis

What is Metacarpal index (MCI) ?

This is calculated by measuring the average length of the second, third, fourth and fifth metacarpals, and the average midwidth of the same.
The average length of the four metacarpals/ The average midwidth of the four metacarpals

If MCI is > 8.4, it indicates presence of Marfan's svndrome (Normal MCI =15.4 to 7.9).

How will you clinically differentiate between Marfan syndrome and homocystinuria

Marfan's syndrome is characterised by the following
  • It is a connective tissue disorder
  • It is transmitted as an autosomal dominant trait
  • Bones are normal
  • Mitral valve prolapse and dilatation of the aortic root and sinus of Valsalva may be present
  • There is no mental retardation
  • There is superoateral subluxation of the lens
Homocysinuria is characterised by the folowing
  • It is an inborn error of metabolism, due to lack of the enzyme cystathionine synthase, leading to accumulation of homocystine and methionine and a deficiency of cystathionine and cystine
  • It is transmitted as an autosomal recessive trait
  • Mental defect is present
  • Osteoporosis is present 
  • Medial degeneration of the aorta and elastic arteries may be present
  • Arterial  and venous thrombosis can occur
  • Inferolateral subluxation of the lens is seen