Treacher Collins' Syndrome

Synonyms: Mandibulofacial craniosynostosis; mandibulofacial dysostosis,Berry-Treacher Collins syndrome, Franceschetti-Zwahlen-Klein syndrome, Thomson complex

• Treacher Collins' syndrome is a disorder of craniofacial development:¹
• Intelligence is usually normal
• It is an autosomal dominant disorder with variable expression. The critical region is at chromosome 5q31.3-32.²
• More than half of all cases are thought to be new mutations because there is no family history of the disease.
• There is a great deal of clinical and genetic variation.³

Incidence is approximately 1 in 50,000 live births.²

• The main features are antimongoloid palpebral fissures, coloboma of lower eyelids, eyelash malformations, molar defects, preauricular hair displacement, flat cheekbones (hypoplastic zygomatic arches), micrognathia and "fish-like" facial appearance.
• The common features are macrostomia, low-set ears and ear defects, high-arched palate, nasal deformity, teeth malocclusion, open bite and conductive hearing loss.
• Other abnormalities, e.g. cleft palate, colobomas of the upper lid, hypertelorism and mental retardation, are infrequent.
• In severely affected patients, the airway is compromised by the mandibular deficiency, glossoptosis and choanal atresia. Sleep apnoea and sudden infant death syndrome may occur.

• Similar syndromes include oculoauriculovertebral dysplasia and Goldenhar syndrome.
• However the only syndrome that Treacher Collins' syndrome resembles in its facial aspects is Nager's acrofacial dysostosis.²

• Diagnosis is essentially made on clinical features. A thorough assessment must be made for all associated features, especially those affecting breathing, and complications, e.g. conductive hearing loss.
• Chorionic villus sample for DNA analysis if there is a family history.
• Otherwise diagnosis is at antenatal ultrasound in mid-trimester.⁴

• The spectrum and degree of deformities are extensive and therefore the nature and intensity of management is also very variable.
• In severe cases the airway must be evaluated and secured from birth. Either positioning alone or tracheostomy is required to manage the airway, and a gastrostomy required for feeding.
• Operative correction of cleft palate.
• Operations of choanal atresia or mandibular lengthening are performed at the age of 2 to 3 years or later.
• The timing of bone and soft tissue reconstruction will vary but bone reconstruction should usually precede soft tissue corrections.
• Autogenous tissues, e.g. ribs or iliac bone, should be used and synthetic materials avoided.
• Soft tissue reconstruction includes correction of lower eyelid coloboma and ear reconstruction.
• Hearing and speech: hearing aids, speech therapy.
• Affected children and their families may need a great deal of support.

• Feeding difficulty
• Hearing loss
• Speech delay
• Hearing and speech difficulties may lead to educational difficulties.
• Self-awareness and bullying resulting from the affect on appearance may lead to psychological difficulties.

• Become normally functioning adults with normal intelligence
• Careful attention to any hearing problem is essential in order for the child to realise their full potential.

• Genetic counselling for prospective parents with a family history of Treacher Collins' syndrome.