Atelosteogenesis type I

Background

Atelosteogenesis type I is a condition that becomes evident at birth, with clinical features including abnormal facies, prominent forehead, hypertelorism, depressed nasal bridge with a grooved tip, micrognathia, cleft palate, severe short-limbed dwarfism, joint dislocations of the hip, knee, and elbow, club feet, and cardiorespiratory failure. The cardiorespiratory failure results from pulmonary hypoplasia or tracheobronchial hypoplasia.

The condition is caused by mutations in the filamin B (FLNB) gene. Diagnosis can be made antenatally using ultrasound or magnetic resonance imaging, and radiological findings include severe platyspondyly, distally tapered or absent humeri and femurs, shortened or bowed radii, ulnas, and tibias, hypoplastic pelvis and fibulas, and deficient ossification of metacarpals and phalanges.

Infants may be stillborn, and those live-born do not survive long. The differential diagnosis includes achondroplasia, achondrogenesis, atelosteogenesis III, boomerang dysplasia, campomelic dysplasia, Ellis–Van Creveld syndrome, hypophosphatasia, Melnick Needles syndrome, metatropic dysplasia, osteogenesis imperfecta, Roberts syndrome, short-rib polydactyly syndrome, and thanatophoric dysplasia.