pendred-syndrome : Symptoms, Causes, Treatment & Prevention

What is Pendred Syndrome?

Pendred syndrome is a disorder typically associated with hearing loss and a thyroid condition called a goiter. A goiter is an enlargement of the thyroid gland, which is a butterfly-shaped organ at the base of the neck that produces hormones. If a goiter develops in a person with Pendred syndrome, it usually forms between late childhood and early adulthood.

What causes Pendred Syndrome?

Pendred syndrome can be caused by changes, or mutations, to a gene known as SLC26A4 (also referred to as the PDS gene) on chromosome 7. Because it is a recessive trait, a child needs to inherit two mutated SLC26A4 genes—one from each parent—to have Pendred syndrome. The child's parents do not need to have Pendred syndrome to be a carrier of a mutation in the SLC26A4 gene.

What are the symptoms of Pendred Syndrome?

The symptoms of Pendred syndrome are:

• Sensorineural hearing loss present at birth
• Inner ear changes and enlargement of the thyroid gland
• Balance problems caused by altered vestibular function

How common is Pendred Syndrome?

The frequency of Pendred syndrome is unknown, but some researchers believe it is responsible for 1 in 10 infants who are born deaf.

How is Pendred Syndrome transmitted?

Pendred Syndrome is genetically transmitted from parent to child in a recessive manner, which means that an affected individual must inherit one copy of the non-functioning gene from each parent. Carriers who only have one copy of the gene (i.e. one normal gene and one mutated gene) do not manifest any of the signs of the condition, but have a 1 in 2 chance of passing on the defective gene to their children (who would then also be carriers only), and a 1 in 4 chance of having an affected child if the other parent is also a carrier. Pendred Syndrome affects men and woman equally, and does not have any ethnic predisposition.

How is Pendred Syndrome treated?

Treatment for Pendred syndrome focuses on addressing hearing loss. Children with the condition should be fitted for hearing aids early in life. Cochlear implants show some promise for restoring some hearing to people who are severely to profoundly deaf. Children should receive special educational programs for the hearing-impaired.

For those who develop goiters large enough to cause breathing or swallowing difficulties, treatment may include radioactive iodine to shrink the swelling or surgery to remove all or part of the thyroid.