Stickler syndrome: eyes, hearing, joints and retinal detachment risk

Stickler syndrome is a genetic condition that affects connective tissue. Contact, the charity for families with disabled children, describes its main effects as being on the eyes, joints, hearing and palate, although some subgroups do not affect all of these areas. Retina UK explains that it is caused by a change in a gene that helps to make collagen, which it describes as the 'glue' that holds the body together.

Retina UK states that there are at least 11 distinct subgroups, which differ in the gene involved and pattern of inheritance, and gives an estimated prevalence of 1 in 7,500 people in the United States and Europe. Contact, in an older entry, refers to 8 identified types, which reflects how the classification has developed.

According to Retina UK, features vary widely and individuals may not have all of them. It groups them into the following areas.

• Eyes: short-sightedness (myopia), retinal holes, giant retinal tears and retinal detachment, cataracts, astigmatism, vitreous degeneration, squint and glaucoma.

• Ears: conductive, sensorineural or mixed hearing loss that can worsen over time, and glue ear with frequent ear infections.

• Joints and bones: hypermobility particularly in childhood, joint pain and stiffness, early-onset osteoarthritis, knock knees, curvature of the spine and, in some, hip degeneration.

• Face and mouth: flat cheeks and nasal bridge, small jaw, palate differences, split uvula and orthodontic problems. Pierre Robin sequence (small jaw, cleft palate and tongue position problems that can cause breathing, feeding and speech difficulties) can occur.

The retina is the light-sensitive layer at the back of the eye. In retinal detachment it separates from the back of the eye, and Retina UK says it can cause blindness if left untreated. Cambridge University Hospitals underlines that accurate diagnosis helps clinicians provide appropriate care, because the risk of detachment differs a great deal between subtypes.

Retina UK advises that affected people should be made aware of the symptoms of retinal detachment so they can have their eyes assessed immediately. It also says retinal detachment needs prompt surgery to preserve vision and can recur even after successful surgery, and that some doctors recommend prophylactic cryotherapy in certain cases. People with ocular forms may be advised to avoid contact sports because of the risk. Sudden new floaters, flashes of light or a shadow or curtain across vision should lead to urgent same-day assessment by an eye casualty or A&E.

Retina UK states that diagnosis is made through clinical examination and family history, with genetic testing to confirm the diagnosis and determine the precise gene change. Contact makes the same point. Early identification matters because it allows surveillance and prompt treatment of complications such as retinal detachment or skeletal differences.

NHS England funds a highly specialised Stickler syndrome service at Cambridge University Hospitals. The service says it provides accurate clinical and molecular genetic diagnosis and subclassification for patients and families in England, and is building a central patient registry. It receives referrals from healthcare professionals, and Retina UK notes that NHS England funds a free referral through your GP. At the first appointment the team tries to complete all diagnostic testing, which can take two to three hours, and a specialist nurse takes a family history to draw a family tree. A hearing test and blood tests may also be arranged.

Contact says there is no cure, but early diagnosis and preventative surgery can substantially reduce the risk of blindness from retinal detachment, and a detachment that does occur can be repaired surgically. Regular checks by an eye specialist are vital. Treatment focuses on the specific problems that appear and may involve a multidisciplinary team that can include a geneticist, paediatrician, orthopaedic surgeon, rheumatologist, ophthalmologist, vitreoretinal specialist, audiologist, orthodontist and others.

Retina UK says that if one parent is affected there is a 50 percent chance of a further child also having it, and that it can also occur as a new change where neither parent has it. Contact adds that preimplantation genetic diagnosis is now feasible and that ultrasound screening may identify cleft palate in pregnancy.

Stickler Syndrome UK is a registered charity offering support and information to families, teachers and healthcare professionals. Retina UK runs a helpline and peer support groups for people affected by inherited sight loss.

In England the national NHS service means diagnosis and sub-classification are available at no charge through a GP referral. Private eye, hearing and orthopaedic care can be used for individual problems, but it helps to share findings with the NHS eye and genetics teams so surveillance for retinal detachment stays coordinated.