Other names known as deafness with goiter' and 'Goiter-deafness syndrome', Pendred syndrome is an inherited condition that affects the body's ability to make a protein called Pendrin. Pendrin is responsible for transporting negatively charged particles, into and out of cells. This is important for normal function of both the inner ear and the thyroid (a butterfly-shaped organ at the base of the neck). Pendred syndrome is a common form of syndromic deafness (hearing loss that occurs with signs and symptoms affecting other parts of the body).
Affected individuals may develop a goiter, a large swelling at the base of the neck caused by thyroid enlargement. This symptom usually appears several years after a hearing loss has been diagnosed. It can happen at any time during late childhood, adolescence, or adulthood. Pendred syndrome does not usually affect thyroid function, however goiters can put pressure on the esophagus and windpipe, interfering with the act swallowing and breathing.
People with the condition are usually born with a severe to profoundly hearing loss, although some lose their hearing rapidly in infancy or early childhood and others have only moderate hearing loss that does not worsen over time.
Pendred syndrome may also cause balance problems caused by dysfunction or malformation of the vestibular system (part of the inner ear responsible for balance), aadditionally, a structure called the vestibular aqueduct (a bony canal that connects the inner ear to the brain cavity) is unusually large in people with Pendred syndrome. An enlarged vestibular aqueduct is a characteristic feature of Pendred syndrome, but it is not the cause of hearing loss in people with this condition.
It is believed that Pendreds may be responsible for 1 in 10 infants who are born deaf.
Treatment for Pendred syndrome focuses on addressing hearing loss. Children with the condition should be fitted for hearing aids early in life. The use of cochlear implants may restore some hearing to people who are severely to profoundly deaf.
For those who develop goiters large enough to cause breathing or swallowing difficulties, treatment may include shrinking the swelling or surgery to remove all or part of the thyroid.