asphyxiating thoracic dysplasia
description
asphyxiating thoracic dysplasia (jeune syndrome) is an uncommon disorder in which there is a narrow thoracic cage, mild to moderate rhizomelia and characteristic radiographic findings in the ribs and pelvis. polydactyly and renal anomalies may also be present. clinical expression is wide ranging from latent to lethal forms. typically, there is respiratory distress in the neonatal period which may result in respiratory failure and death. survivors commonly develop progressive renal insufficiency and hepatic fibrosis although cases have been reported without this pathology. the mode of inheritance is autosomal recessive.
diagnosis
the thorax is long and narrow, with handlebar clavicles and horizontal ribs. mild to moderate shortening of the long bones is often seen and in about two thirds of the cases the proximal femoral ossification center is present at birth. the pelvis is small, with square-shaped iliac wings and acetabular margin has a trident appearance. antenatal diagnosis can be challenging, with only the most severely affected cases being potentially recognizable prenatally. the chest circumference and long bones are often within the normal range in the early second trimester, but these measurements may fall below 2 standard deviations as the pregnancy progresses. recently normative data for sonographic measurement of the fetal rib cage perimeter to thoracic circumference ratio has been produced. in normal pregnancies this ratio was found to be 0.67+/- 0.004 which was independent of gestational age. in cases with certain skeletal dysplasias the ratio was significantly decreased. this technique requires further evaluation but may prove useful.
differential diagnosis
in chondroectodermal dysplasia polydactyly is almost always present and congenital heart disease is encountered in 60 % of cases; however, the differential diagnosis between these two disorders may be practically impossible in atypical cases. short-rib polydactyly syndromes can be differentiated by severe micromelia, rib shortening and polydactyly. barnes syndrome (thoracolaryngopelvic dysplasia) is an autosomal dominant condition with a narrow bell-shaped thorax and laryngeal stenosis.
sonographic features
mild to moderate rhizomelic long bone shortening
premature ossification of the proximal femoral ossification center
long and narrow thoracic cage with normal or small thoracic circumference
horizontal ribs with mild shortening and irregular bulbous ends
polydactyly occasionally present
polyhydramnios
absent fetal respiratory movements
increased nuchal translucency at 10-14 weeks
associated syndromes
- adams-oliver
- oromandibular-limb hypogenesis (moebius)
references
- skiptunas sm, weiner s early prenatal diagnosis of asphyxiating thoracic dysplasia (jeune syndrome): value of fetal thoracic measurement j ultrasound med 6:41-43
- elejalde br, elejalde mm, pansch d prenatal diagnosis of jeune syndrome am j med genet 21:433-438
- schinzel a, savodelli g, briner j, schubiger g prenatal sonographic diagnosis of jeune syndrome radiology 154:777-778
- lipson m, waskey j rice j, adomian g, lachman r, filly r, rimoin d prenatal diagnosis of asphyxiating thoracic dysplasia am j med genet 18:273-277
- zimmer ez, weinraub z, raijman a, pery m, peretz ba antenatal diagnosis of a fetus with an extremely narrow thorax and short rib dwarfism j clin ultrasound 12:112-114
- oberklaid f, danks dm, mayne v, campbell p asphyxiating thoracic dysplasia: clinical, radiological, and pathological information on 10 patients arch dis child 52:758-765
- kozlowski k, szmigiel c barylak a, stopyrowa m difficulties in differentiating between chondroectodermal dysplasia (ellis-van creveld syndrome) and asphyxiating thoracic dystrophy australasian radiol 16:401-410