Marfan syndrome

Definition

 

Inheritable disorder of connective tissue

 

Epidemiology

 

Male = Female

1 in 5000

 

Nil geographical variation

 

Aetiology

 

AD

 

Gene

- FNB1

- fibrillin

- chromosome 15

 

Now diagnosed by genetic studies

 

Pathology

 

Fibrillin is a component of elastic fibres

 

DDx

 

Homocystinuria

- no FHx

- diagnose via urinalysis

- presents the same way

 

Ehler Danlos

- very fragile, mobile skin

 

Ehler Danlos Fragile Skin

 

Stickler's

- mental impairment

 

Clinical Features

 

Major criteria

- FHx

- pectus excavatum requiring surgery

- pectus carinatum

- arm span : height ratio > 1.05

- wrist sign (LF and thumb overlap)

- thumb sign (projects past ulna border palm)

- scoliosis > 200

- pes planus

- protrusio

 

Minor

- pectus excavatum

- minor scoliosis

- thoracic lordosis

- high arch palate

- joint hypermobility

 

Need 2 major or 1 major / 2 minor

 

Skeletal

 

Arachnodactyly

- long fingers and toes

 

Thumb sign

- protrudes past ulna border palm

 

Pectus excavatum / carinatum

 

Ligamentous laxity

- genu valgum

- PFJ instability

 

Scoliosis

- 60% patients

- right thoracic

- 20% need OT

- complicated by thoracic lordosis

 

Spondylolithesis

 

Dural ectasia

 

Flat feet

- ligamentous laxity

 

Protrusio

- consider triradiate cartilage fusion

 

Elbow joint contractures

 

Extra-skeletal

 

High arched palate

 

Lens dislocation

- also short sighted, astigmatism

 

CVS

- AR, MR

- aneurysm

- dissection

 

Spontaneous Pneumothorax