Asphyxiating thoracic dysplasia

Asphyxiating thoracic dysplasia (also, also known as Jeune syndrome), is a type of rare short limb skeletal dysplasia, which is primarily characterised by a constricted long narrow thoracic cavity, cystic renal dysplasia and characteristic skeletal features. It is also sometimes classified as one of the short rib polydactyly syndromes ^ref.

Epidemiology

Autosomal recessive inheritance with estimated incidence at around 1:70,000 births ^ref.

Pathology

Genetics

• thought to carry an autosomal recessive inheritance ⁸

Complications

• development of pulmonary hypoplasia
• renal failure from cystic renal disease
• development of hepatic cirrhosis

Radiologic features

There can be significant variation in the clinical spectrum. Features include:

Skeletal

• thoracic
  • short narrow elongated chest shape (can be bell shaped-shaped): may be seen as a narrow fetal thorax antenatally
  • high riding clavicles ("handlebar clavicles")¹²
  • irregular costochondral junctions¹³
• other skeletal
  • dysplastic acetabula with flat acetabular roof ¹³
  • trident acetabula
  • short and flared illiaciliac bones ¹³
  • ischial and pubic bones with medial and lateral spurs ¹³
  • premature closure of capital femoral epiphysis
  • short broad phallangesphalanges
  • short distal limbs (acromelic dwarfism)
  • polydactyly (often post axial): 14% ⁴
  • coned ephiphysesepiphyses

Abdominopelvic

• cystic renal disease
• cystic pancreatic disease ⁹
• hepatic dysfunction ^9,11

Treatment and prognosis

The prognosis can be variable as a result of the marked phenotypic variation. In those who survive severe pulmonary symptoms in the first year of life, there can be an improvement in the skeletal and thoracic deformity with relative growth of the thoracic cage post birth. Most of the mortality is due to respiratory compromise.

History and etymology

It was first described by M Jeune in 1955 ².

See also

• short rib polydactyly syndromes