What is Usher Syndrome?

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Patient Presentation
A 2-year-old female came to clinic with a 2 day history of upper respiratory infection symptoms, pulling on her ears, and being cranky. She had a temperature of 38.8°C maximum that improved with acetaminophen. The past medical history revealed 4 previous otitis media infections with the last one being 6 months ago. The pertinent physical exam showed a cranky appearing female with a temperature of 38.2°C, respiratory rate of 24 and growth parameters that were 50%. HEENT showed copious clear rhinorrhea and bilateral tympanic membranes that were red and bulging with yellow purulent material behind the tympanic membrane. There was no membrane movement in either ears.

The diagnosis of bilateral acute suppurative otitis media was made. The mother said that she was glad to know what the problem was but was very anxious because this was her 5th ear infection and she wanted a referral to an otolaryngologist. “I don’t really want her to have surgery for her ears, but my cousin’s baby was born deaf and he’s just been diagnosed with something called Usher. I looked it up on the Internet and it’s really bad. They can have eye problems too. I’m really worried about her hearing and think I would feel better if I knew she wasn’t going to have hearing problems,” she explained. “I’m very sorry to hear about your cousin’s child. I don’t remember exactly what Usher is, but will try to find out. Your daughter’s newborn hearing test should have been normal otherwise we would have sent her to the ear doctor already but I’ll check to make sure. Have you ever thought that she was having problems hearing, either now or before?” the pediatrician inquired. “I think her test when she was born was normal and I’ve never been worried, but she’s had these infections and now this baby who is deaf. I’m just very worried,” she replied. “We’ll I can understand that. It is not unreasonable to have her hearing tested after having 5 ear infections, but her last one was a while ago and for most children the ear infections stop as they get older and there are usually no problems with long-term hearing loss. I’ll order a hearing test for her after this ear infection is over. In the meantime, I’ll try to find out more about Usher, ” she offered. “I think I will feel a lot better after I know that her hearing is normal,” the mother said.

Discussion
Over 7000 diseases are considered rare disorders according to the National Organization for Rare Disorders® (NORD, rarediseases.org). NORD is a patient advocacy organization dedicated to individuals with rare diseases and the organizations that serve them. They have information on about 1200 rare diseases on their website (https://rarediseases.org/for-patients-and-families/information-resources/rare-disease-information/).

Hearing loss (HL) is not rare and is a common problem across the ages. It affects 360 million people worldwide which is about 5% of the population. There are many causes of hearing loss and a differential diagnosis can be reviewed here. HL can be classified as congenital vs acquired, with congenital being further classified according to the genetic inheritance (e.g. recessive, dominant, sex-chromosome), onset, severity and whether it is associated with syndromes or not.

Retinitis pigmentosa (RP) is a group of retinal degenerative diseases that have loss of photoreceptors and retinal pigment deposits. Non-syndromic RP causes visual deficits over several decades. Initial symptoms are night blindness and later patchy peripheral vision losses that evolves into scotoma, tunnel vision and blindness. There are many syndromes which have RP as part of their symptoms with Usher syndrome (14% of all RP cases) and Bardet Biedel syndrome as two of the most common ones.

Learning Point
Usher syndrome (US) was described as early as 1858, but it is named for British ophthalmologist Charles Usher who noted the genetic inheritance.
US has later onset RP and congenital, bilateral, neurosensory hearing loss.
Of the syndromes known to affect both hearing and vision, “…about half of the affected cases are caused by mutations attributed to Usher syndrome.”
US is autosomal recessive with an estimated prevalence of 3-10/100,000 people. There are multiple genes involved (chromosomes 1, 3, 10, 11, 14, 21).
There are 3 major types and a possible 4th.

  • Type I – 70-75% of patients – has congenital severe to profound hearing loss, congenital vestibular dysfunction, RP begins in usually < 10 years
  • Type II – 26% of patients – has congenital moderate to severe hearing loss (quite “hard of hearing”), no vestibular dysfunction, RP is diagnosed ages 10-40 years
  • Type III – 4% of patients – has variable progression hearing loss that starts in years 20-30, variable vestibular dysfunction, RP starts in 20s.
    It is least common, but more common in some populations including Ashkenazi Jewish and Finnish populations.

  • Type IV – its existence is being debated by researchers and may be X-linked recessive

Treatment is directed by ophthalmologists and otolaryngologists who along with audiologists, speech and language pathologists and other professionals may help patients with different therapies. Some patients take Vitamin A as part of their treatment.

Questions for Further Discussion
1. How good are vision and hearing screening tests? A review can be found here https://pediatriceducation.org/2011/11/14/how-good-are-hearing-and-vision-screening-tests-in-children-2/
2. What are indications for referral to a geneticist?
3. What are indications for cochlear implants?

Related Cases

To Learn More
To view pediatric review articles on this topic from the past year check PubMed.

Evidence-based medicine information on this topic can be found at SearchingPediatrics.com, the National Guideline Clearinghouse and the Cochrane Database of Systematic Reviews.

Information prescriptions for patients can be found at MedlinePlus for this topic: Usher Syndrome

To view current news articles on this topic check Google News.

To view images related to this topic check Google Images.

To view videos related to this topic check YouTube Videos.

Usher Syndrome. National Organization for Rare Diseases. Available from the Internet at https://rarediseases.org/rare-diseases/usher-syndrome/ (cited 9/7/17).

Hamel C. Retinitis pigmentosa. Orphanet J Rare Dis. 2006 Oct 11;1:40.

Koffler T, Ushakov K, Avraham KB. Genetics of Hearing Loss: Syndromic. Otolaryngol Clin North Am. 2015 Dec;48(6):1041-61.

Usher Syndrome, Type i; USH1 #276900. Online Mendelian Inheritance in Man.
Available from the Internet at Koffler T, Ushakov K, Avraham KB. (rev. 3/8/16, cited 9/6/17).

Author
Donna M. D’Alessandro, MD
Professor of Pediatrics, University of Iowa

Published