Handbook of Genetic Counseling/Acrofacial Dysostosis Syndrome

Acrofacial Dysostosis Syndrome

Definition

edit
  • A condition resulting from problems in the development of the first & second branchial arches. The first arches produce the nerves and muscles for chewing, the lower jaw, 2 middle ear bones, and a small part of the ears. The second arches produce the nerves & muscles of facial expression, 1 middle ear bone, most of the external ears, and parts of the bone above the larynx.

Characteristics

edit
  • underdevelopment of the cheek and jaw area (micrognathnia and malar hypoplasia)
  • feeding and breathing problems in infancy
  • down-sloping palpebral fissures
  • absence of the lower eyelashes
  • lack of development of the internal & external ear with temporary or long-term hearing loss
  • possible cleft palate
  • underdevelopment or absence of the thumb
  • shortened forearms & poor movement in the elbow/limited range of arm motion
  • stomach & kidney reflux
  • normal intellect
  • possible missing, overlapping, or webbing of the toes, clubfeet, hip dislocation, or underdeveloped ribs may occur

Incidence

edit
  • very rare

Etiology

edit
  • Unknown - may represent new mutations of an autosomal dominant trait or variable expression
  • Genetic testing is highly recommended

Genetics

edit
  • located on chromosome 9q32

Prognosis

edit
  • may be lethal is there is lung hypoplasia

Management

edit
  • Possible need for a tracheostomy to help with breathing
  • Possible need for a gastrostomy tube to assure proper nutrition
  • craniofacial surgery to the jaw, cleft palate, & ears
  • plastic surgery for eye, jaw, ears
  • orthopedic surgery for arms, hands, feet, or toes
  • hearing screens
  • speech therapy for proper development
  • physical therapy to improve use of hands and feet

Differential Diagnosis

edit
  • Miller Syndrome
  • Genee-Wiedemann Syndrome
  • Treacher Collins Syndrome
  • Pierre Robin Sequence
  • Franschetti-Klein Syndrome
  • Goldenhar-Gorlin Syndrome
  • Oral-Facial-Digital Syndrome
  • Juberg-Hayward Syndrome (Orocraniodigital Syndrome)
  • Hemifacial Microsomia (HFM)
  • Trisomy 18 (micrognathnia & distal ectromelia)

References

edit
  • FACES: The National Craniofacial Association www.faces-cranio.org
  • The Foundation for Nager and Miller Syndromes (FNMS) www.nagerormillersynd.com
  • NORD www.rarediseases.org
  • Gorlin's Syndromes of the Head and Neck p. 652-3

Notes

edit

The information in this outline was last updated in 2001.