Hearing loss and rare diseases: What's the connection?Hearing loss and rare diseases: What's the connection?
Edith Veitch, now 17, was 10 when an audiologist diagnosed her hearing loss and fitted her with aids.
Her mother, Margo, a community college instructor in Illinois, is unsure when the hearing loss set in. “We don’t have [hearing loss] in the family so we weren’t looking for it,” she said. In school, because Edith has an intellectual disability, she had been assigned a companion to repeat things to her in class.
Her family then opted for a deaf and hard-of-hearing program—the classes were small and it wasn’t clear how quickly her hearing might deteriorate. Many of her classmates have cochlear implants or rely mainly on ASL. But, Edith's hands are small and it is difficult for her fingers to form shapes. “When her peers sign to her, she was signing back, but she has become more self-conscious,” Veitch said.
Eventually her family learned that Edith has Myhre syndrome, a rare disorder of the connective tissue. Fortunately, as with many rare diseases, hearing aids have been an effective treatment.
"She appreciates being able to hear,” Veitch said of her daughter's hearing aids.
Many rare diseases can cause hearing loss
Scientists have identified 7,000 diseases, like Myhre syndrome, that are considered rare. As defined in the U.S by the Orphan Drug Act of 1983, rare diseases each affect fewer than 200,000 people. However, up to 30 million Americans live with a rare disease.
Many, but not all, have been traced at least in part to genes, with signs that appear at birth or early in life.
The degree of loss can vary widely from person to person. For some people, hearing aids will be sufficient. For others, cochlear implants and/or learning American Sign Language will be recommended.
In many cases, a rare disease can cause multiple anatomical and functional changes in the ears. A prime example of this is Turner syndrome.
Hearing loss may be apparent at birth or soon after
Because of state programs aided by the federal government, nearly all American babies have a hearing test within the first month of life. About two or three out of every 1,000 newborns in the U.S. have a detectable hearing loss in one or both ears.
The hearing loss may be a sign of a rare disease. Babies with Mondini dysplasia, for example, are born with one and a half coils in the cochlea instead of the standard two, in either one or both ears. Most children with this condition have profound hearing loss. They may need a surgical repair, as well as a cochlear implant, but some can benefit from hearing aids. Babies with KID syndrome, Donnai-Barrow syndrome, and Wildervanck syndrome—among other rare diseases—may have hearing loss.
Sometimes the loss is not present at birth but develops soon after. Babies with the most common and severe form of Krabbe disease develop symptoms in the first six months, which include fevers, muscle weakness and hearing and vision loss.
Or it develops later
And sometimes, as with Edith, the hearing loss comes much later. People with Alport syndrome, for example, often lose hearing in late childhood or early adolescence and may be treated with hearing aids. Similarly, people with Alström syndrome tend to have progressive hearing loss in both ears that may begin in childhood and be treated with hearing aids.
Other notable rare disorders linked to hearing loss
Symptoms can be unpredictable
Symptoms can vary widely in severity among people with the same disorder. And intellectual ability may or may not be affected. For example, children with Carpenter syndrome may be of normal intelligence but it is common for them to have an intellectual disability and sometimes hearing loss.
Such is the case with Myhre syndrome, the condition that Edith has. At least 80 percent of people with it have a hearing impairment, as well as intellectual disability and stiff joints.
Although Edith’s hearing did decline, she does not have a profound loss. She happily wears her hearing aids, even at home.
She also takes an art class with 32 students, and as her mother noted, “many don’t know she has hearing aids."
For more information
For more information on rare diseases, see Global Genes, the National Organization for Rare Disorders (NORD), and the Genetic and Rare Disease Information Center (GARD). If you suspect you or a loved one has hearing loss, visiting our large online directory of consumer-reviewed hearing clinics is a good next step.