Marfan Syndrome Flashcards Preview

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Flashcards in Marfan Syndrome Deck (39)
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1
Q

What is the inheritence of Marfan syndrome?

A

Autosomal dominant

2
Q

Which type of systemic disease?

A

Connective tissue disorder

3
Q

Marfan syndrome: chromosome and gene

A

Chromosome 15

Gene: Fibrillin-1

4
Q

Other disorders associated with Fibrillin-1 mutation

A

Familial Ectopia lentis

Weill Marchesani syndrome

5
Q

Sex/gender of Marfan syndrome

A

both male and female are affected

6
Q

What is the carrier state?

A

NO carrier state

one mutated gene (heterozygote) will manifest disease

7
Q

Can Marfan syndrome skip a generation?

A

NO

normally appears in every generation

8
Q

Ratio of new mutation

A

Among the affected person, 25% are first affected/new mutation

9
Q

Arm span to body height ratio in Marfan syndrome

A

>1.05

Normal: <1.05

10
Q

Stature of Marfan syndrome

A

Tall stature with disproportionately long limbs (= dolichostenomelia)

11
Q

Intelligence in Marfan syndrome

A

Usually normal

12
Q

Eye features of Marfan syndrome

A

Ectopia lentis (superotemporal/upward lens dislocation)

Blue sclera

Myopia

Peripheral retinal degeneration >>> retinal detachment

13
Q

Head-neck features of Marfan syndrome

A

High arched palate ( & narrow)

Crowded teeth

High-arched neck

14
Q

Limb features of Marfan syndrome

A

Arachnodactyly

Steinberg sign positive

Walker-Murdoch sign positive

Joint laxity

Pes planus in foot

15
Q

Arachnodactyly

A

Also called ‘spider finger’

Arachnid = Spider

Fingers are abnormally long, slender, curved liked spider legs +

all or few fingers can be bent backwards of 180 degree

16
Q

What are the specific signs of Marfan’s syndrome?

A

Steinberg sign positive

Walker-Murdoch sign positive

17
Q

Steinberg sign

A

Fold your thumb >> then close your fist >> if thumb tip extends beyond the palm of hand >> Steinberg sign positive

18
Q

Walker-Murdoch sign

A

Grip your wrist with your opposite hand >>> if thumb and fifth finger of hand overlap with each other >>> positive Walker-Murdoch sign

19
Q

Radiological features of Marfan syndrome

A

Protrusio acetabulae

Dural ectasia in spinal MRI

20
Q

Trunk features in Marfan syndrome

A

Pectus Excavatum or Carinatum

Scoliosis >20degree

21
Q

Cardiac defects in Marfan syndrome

A

1. Dilation of the aortic root sinuses (90%cases of Marfan) >>> leads to Aortic regurgitation

2. Mitral valve prolapse (MVP) (75%cases of Marfan)

3. Aortic dissection

22
Q

The most common cardiac defect in Marfan syndrome

A

Aortic root dilation >>> leading to >>> Aortic regurgitation

23
Q

The second common cardiac defect in Marfan syndrome

A

Mitral valve prolapse (MVP) in 75% cases

often AR and MVP are present together

24
Q

Murmur of MVP (Mitral valve prolapse)

A

Late systolic murmur

25
Q

Pulmonary defect in Marfan syndrome

A

Repeated spontaneous pneumothoraces

Apical blebs on chest radiograph

26
Q

Skin feature in Marfan syndrome

A

Striae

27
Q

Blood defect in Marfan syndrome

A

Increased risk of thromboembolic disorder

28
Q

Similarity between marfan syndrom and homocystinuria

A

Marfan syndrome may present with high homocystine level (homocystinuria)

Homocystinuria may present with marfanoid habitus (e.g. arachnodactyly etc.)

29
Q

Difference between Marfan syndrome and homocystinuria

A

Marfan syndrome: Autosomal dominant

Homocystinuria: Autosomal recessive

Marfan syndrome: upward ectopia lentis

Homocystinuria: downward ectopia lentis

30
Q

Marfan syndrome is diagnosed by-?

A

Modified Ghent criteria

31
Q

Why did Ghent criteria need to be modified?

A

Due to emerging spectrum of mutations in fibrilin-1 associated disorders (other than Marfan syndrome)

32
Q

What is the significance of new modified Ghent criteria?

A

It placed greater weight on >>>

  • Cardiac features
  • Aortic dilatation
  • Ectopia lentis
33
Q

How ‘systemic score’ is calculated to be used in modified Ghent criteria?

A

A systemic score is calculated, according to presence of >>>

  • Musculoskeletal findings
  • Radiological findings
  • Skin findings

>> weighted according to their diagnostic specificity

34
Q

In patient without family history >> modified Ghent criteria to diagnose Marfan syndrome?

A

Any of the following four conditions >>> Diagnosis of Marfan syndrome:

  • Aortic dilatation (Z score greater than or equalling 2) + Ectopia lentis
  • Aortic dilatation (Z score greater than or equalling 2) + Fibrillin-1 gene mutation
  • Aortic dilatation + systemic score greater than or equalling 7
  • Ectopia lentis and Fibrilin-1 mutation

*** This Fibrillin-1 gene mutation should be known to be associated with Marfan syndrome, not other disorders

35
Q

In patient with family history >> modified Ghent criteria to diagnose Marfan syndrome?

A

Family history in first degree relatives = parent, siblings, child

If presence any of >>

  • Family history + Aortic dilataion
  • Family history + Ectopia lentis
  • Family history + Systemic score greater than or equalling 7

>>>>> Dx of Marfan syndrome

36
Q

Treatment of Marfan syndrome

A

ACE inhibitors

Beta blockers

If lens is fully dislocated from pupil aperture >>>>> Aphakic lens

37
Q

Monitoring in Marfan syndrome

A

Regular echocardiography

38
Q

Life expectancy

A

Around 40 to 50years

If undiagnosed >>> high risk of death in 30s to 40s

39
Q

Main cause of death in Marfan syndrome

A

Aortic dissection (AD) & other heart defects