What is Treacher Collins syndrome?

Treacher Collins syndrome or Franceschetti-Klein syndrome is a rare congenital disease, due to genetic anomalies with numerous consequences on hearing development (deafness), respiratory development, etc. How is the diagnosis made in children or during examinations pregnancy? How is this disease transmitted by parents? What are the clinical consequences and difficulties? All the answers with Dr Eva Galliani, hospital practitioner in the maxillofacial surgery department of Necker hospital (Paris).

Treacher Collins syndrome: what are we talking about?

A rare congenital malformation, Treacher Collins syndrome is characterized by orofacial anomalies and deformities (eyes, cheekbones, ears, jaw, etc.). This syndrome can cause various difficulties and disorders (hearing, breathing, swallowing, etc.) and requires complex and multi-disciplinary care.

Identified in pregnant women from the second ultrasound carried out around 22 weeks of pregnancy, Treacher Collins syndrome (or Franceschetti-Klein syndrome), is a rare congenital malformation. “Associated with the mutation of several genes, this syndrome affects one in 50,000 babies.underlines Dr Eva Galliani, maxillofacial surgeon at Necker hospital in Paris.

Clinical manifestations of Treacher Collins syndrome

Facial features are often characteristic. Indeed, people with Treacher Collins syndrome often have particular features, with the lower face (jaws and chin) poorly developed, very flat cheekbones, eyelids slanting downwards and the outside of the face giving the “drooping eyes” impression. Furthermore, the nasal bones are often quite developed. “These characteristics may be very little marked or, on the contrary, recognizable from birth”says Dr. Eva Galliani.

Jaw and palate malformations

The lower jaw and chin are often small (micrognathism) and sometimes recessed (microretrognathism). People may have difficulty opening their mouth wide and chewing because the joint of the mandible with the skull (temporomandibular joint) is often malformed. “Some teeth may not grow (dental agenesis), overlap or be poorly implanted,” adds the specialist.

Nearly one in three people also have malformations of the palate (too hollow or split), and/or the soft palate which may be split (velar or palatovelar cleft), too short or present a mobility problem. “These malformations can be responsible for speech disorders. continues Dr Eva Galliani.

Eyelid abnormalities

On the side of the temples, the upper eyelids are drooping. “This makes the eyes appear to be tilted slightly down and away from the face.”, explains Dr Eva Galliani. The lower eyelids may be hollow, sometimes slightly split (eyelid coloboma).

Ear malformations

In four out of five people, the visible part of the ears (the pinna) is poorly hemmed, folded, or even almost or completely absent (microtia or anotia). The ear canals may then be very narrow or absent. “Malformations can also affect the small bones located in the middle ear (ossicles), leading to a so-called “transmission” hearing loss.explains the doctor.

Craniofacial injuries

The functional and morphological prognosis is linked to the degree of craniofacial damage. The smaller and more retruded the mandible, the more the child is exposed to an obstructive respiratory disorder.

Respiratory consequences

Treacher Collins syndrome can therefore cause serious medical situations, such as neonatal respiratory distress requiring immediate medical attention. “In the worst case, a tracheotomy or the use of non-invasive nighttime ventilation may be necessary. specifies Dr Eva Galliani. If the child cannot feed properly, enteral nutrition via nasogastric tube which can go as far as the gastrostomy may be considered. “However, we try to avoid as much as possible this type of surgery which remains quite burdensome in terms of daily care.”says Dr. Eva Galliani.

Multidisciplinary care

As malformations can affect the entire orofacial sphere (cheekbones, nose, ears, eyes, mouth, jaw, etc.), the treatment is multidisciplinary and involves different specialists: pulmonologist, pediatrician, maxillofacial surgeon, plastic surgeon, ENT, orthodontist, speech therapist, pediatric dentist. In addition, a psychologist supports the parents and the child throughout their medical and surgical journey. “The role of the psychologist is to offer a space for discussion to the child and his parents to support them during their follow-up. This follow-up also aims to promote in the child a positive self-image, a guarantee good social integration”points out the specialist.

Finally, a genetic consultation is often necessary in order to identify the genetic mutation which caused the malformations, especially if these people wish to have children one day. “These situations require therapeutic education time to prepare them for all the steps they must tackle and to explain to them the different surgical interventions that can be proposed.explains the specialist.

A panel of possible surgical interventions

Indeed, depending on the age of the child, different corrective surgical interventions may be considered. From the age of 6 months, it is possible to close the slit at the mouth. In cases of severe damage to the eyelids and cheekbones from early childhood, we can offer “lipofilling”, a plastic surgery procedure which consists of increasing the volume in the eyelids and cheekbones can also be carried out. Furthermore, from the age of one year, a hearing aid can be fitted. “It is very important to remedy hearing problems as soon as they appear because it affects learning to speak. Thus, certain oral malformations may require orthodontic treatment or even jaw surgery. explains Dr. Eva Galliani.

Although they are possible, these surgical interventions nevertheless remain very cumbersome and require planning several operations, from birth until the end of growth and referral to a reference center.

Proximity with other syndromes

Close to Treacher Collins syndrome in some of its manifestations, Goldenhar syndrome is distinguished by the presence of extra-facial disorders: renal, cardiac and spinal disorders, spinal malformations, etc.

As to Nager syndromethe condition has similarities with Treacher Collins syndrome (facial deformities), but it is distinguished by the presence of damage to the fingers and hands.

These three syndromes are brought together within the rare diseases affecting the head and neck health sector. A dedicated patient association brings together patients affected by these rare genetic anomalies as well as their loved ones: the Coline Association.