Treacher Collins Syndrome
What Is Treacher Collins Syndrome?
Treacher Collins syndrome (TCS) affects the way the bones of the face develop before a baby is born.
TCS — also called mandibulofacial dysostosis and Treacher Collins-Franceschetti syndrome — is caused by a genetic mutation (a change in a person's DNA).
What Are the Signs & Symptoms of Treacher Collins Syndrome?
Symptoms of TCS can be mild or severe. The same TCS mutation can affect one family member much more than another, a difference called penetrance. TCS symptoms can be so mild that a parent may have the mutation and not notice the symptoms (low penetrance) until the mutation is passed to a child who has more obvious symptoms (higher penetrance).
TCS causes changes that are usually symmetrical, meaning both sides of the body look the same. Features of TCS include:
- downward slant of the outer corners of the eyes
- drooping upper eyelids
- notches in the lower eyelids with few, if any, lower lid eyelashes
- small cheekbones
- fewer teeth than usual; they may be crooked and have patchy coloring
- small mandible (lower jaw) causing an overbite (the chin and lower teeth sit back from the upper teeth)
- open or split roof of the mouth (cleft palate) and upper lip (cleft lip)
- small, unusually shaped ears
- small or missing ear openings
- hearing loss because sound is poorly transferred by the tiny bones in the middle ear
What Causes Treacher Collins Syndrome?
Almost all children with TCS have a mutation of one of three genes that control bone growth in and around the face. The TCS mutation causes a change in a baby's growth very early in pregnancy. For a few people with TCS, the gene causing the problem is not known.
Who Gets Treacher Collins Syndrome?
Most of the time, TCS is caused by a new mutation, meaning neither parent has the TCS gene or TCS symptoms. If the mutation is new, the change in the DNA happened just before or soon after fertilization of the egg by the sperm.
If the mutation is not new, the TCS gene was passed from a parent to the child. This is most likely when the parent has only mild TCS symptoms and was unaware of having a genetic mutation.
How Is Treacher Collins Syndrome Diagnosed?
The way a baby's face looks at birth will cause doctors to think about TCS as the most likely diagnosis. X-ray images of the child's facial bones can identify the characteristic features of TCS. Genetic testing can confirm the diagnosis.
If TCS is suspected in other family members, genetic testing can determine whether there's a TCS mutation.
How Is Treacher Collins Syndrome Treated?
Treatment depends on the symptoms, and requires a team of medical specialists, including pediatricians, plastic surgeons, ear nose and throat specialists (ENTs), dentists ophthalmologists, and audiologists.
Treatment begins at birth. Newborns with TCS may have trouble breathing because their airways are narrow. Certain positions, like lying on the stomach, can help make breathing easier. For severe breathing problems, a child might need a tube inserted into the windpipe (called a tracheostomy). Some babies with TCS have problems with feeding, especially when it interferes with breathing. So they might need a feeding tube into the stomach through the nose.
Unless a child with TCS has breathing or feeding problems, most facial reconstruction surgery is done over a number of years when the child is older. Surgery of the face and jaw can improve appearance, and have a positive effect on a child’s self-esteem and social functioning.
Hearing should be checked at birth and routinely as the child grows. Because the inner ear still works well in most children with TCS, hearing aids that transmit sound through the bone instead of the middle ear can work well. Speech-language therapy is often needed.
Kids with TCS need regular eye exams to check for problems with vision, eye movements, and cornea exposure (because they can't close their eyelids completely).
What Else Should I Know?
Children with TCS have normal intelligence and life expectancy.
How other people act around a child with TCS can have a big impact on the child's life and self-esteem. If your child has TCS, offering your love and support will help ensure your child's emotional well-being. If feelings of self-consciousness keep your child from enjoying social events or other activities, find a counselor or psychologist who can help your child work through these difficult emotions.