Usher Syndrome is a relatively common genetic disorder that primarily affects vision and hearing. In some cases, children with a severe form of the disorder are born with substantial balance problems that affect motor coordination.
Who is at Risk?
Usher Syndrome is an inherited disease that requires two recessive genes. This means both parents are carriers of the condition. Not all children born to carriers will develop Usher Syndrome, as children may only receive on copy of the altered gene. If a child is a carrier, they can pass the condition on to their children but they will not develop symptoms. Typically, both parents pass the same mutated gene to the child for the condition to develop.
Symptoms
The symptoms of Usher Syndrome are the same across all forms of the disease. Patients may experience:
- Impaired balance
- Loss of vision
- Loss of hearing
- Deafness
- Blindness
Diagnosis
Doctors will being diagnosis with a complete patient history. Typically, balance issues paired with vision and hearing symptoms, trigger the investigation into Usher Syndrome. Patients may undergo an electroretinogram and/or electrostagmogran.
Genetic testing can be used for a definitive diagnosis. The genes affected include:
- MY07A
- USH1C
- CDH23
- PCDH15
- SANS
- USH2A
- VLGR1
- WHRN
- USH3A
Genetic testing is not available for all genes. Testing is reserved for cases where patients have been diagnosed with Usher Syndrome based on hearing, vision and balance tests.
Treatment
Patients with Usher Syndrome cannot slow the progression of the disease, but they can prepare for potential loss of hearing and vision.
Patients with Type 1 are typically born with severe balance problems and complete deafness. While hearing aids don’t typically work to improve hearing, patients do have sight for as many as 10 years. Early diagnosis is crucial for patients with this form of the disease because they can learn to communicate effectively before vision is lost.
Type 2 Usher Syndrome may not affect balance, but hearing and vision are affected. Hearing aids may improve hearing and visual aids may improve sight, though vision loss is progressive.
Type 3 Usher Syndrome is the mildest form of the disease. Though patients will eventually lose hearing and sight, but the decline is much slower than other forms of the disease. Patients can use hearing aids and visual aids throughout life and may not suffer from legal blindness until late adulthood.
Life Expectancy
Prognosis for patients with Usher Syndrome is good. The condition will eventually lead to deafness and blindness, in most cases, but early death is not predicted in severe, moderate or mild cases.