Last updated: October 05, 2022
Years published: 2021
NORD gratefully acknowledges Greg Cichon, MD candidate, Creighton School of Medicine and Heather Gomes, MD, Otolaryngologist, Boys Town National Research Hospital, for the preparation of this report.
Summary
Pendred syndrome is an uncommon genetic disease in children. Patients usually have hearing loss in both ears (often at birth) and a goiter, which is an enlarged thyroid gland in the neck. The goiter typically grows in the teenage years but may present earlier or later.
Pendred syndrome is caused by the lack of a protein called pendrin, which is important in the kidney, ear and thyroid to keep salt levels balanced. Without enough pendrin, the ion levels become unbalanced and cause hearing and balance issues, a swollen thyroid and less commonly electrolyte imbalances. There is no specific treatment, but the symptoms can be managed with thyroid hormone supplements and hearing aids.
The most common symptoms of Pendred syndrome include:
Pendred syndrome is caused by changes (mutations) in three genes (SLC26A4, FOXI1, or KCNJ10) in about 50% of patients, and the other half are due to unknown causes. Mutations in SLC26A4 (also known as PDS), which encodes the protein pendrin, are the most common identifiable causes of Pendred syndrome. Pendrin is found in the inner ear (responsible for hearing and balance), the thyroid (a butterfly-shaped organ in the lower neck which is responsible for controlling metabolism) and kidneys (responsible for filtering waste and controlling salt levels). Pendrin pumps chloride and iodide to maintain their ion balance in the inner ear, thyroid and kidney. Mutations in these genes result in a lack of pendrin, so the ion levels become unbalanced and cause hearing and balance issues, a swollen thyroid and less commonly electrolyte imbalances.
Pendred syndrome is an autosomal recessive genetic condition. Recessive genetic disorders occur when an individual inherits a non-working gene from each parent. If an individual receives one working gene and one non-working gene for the disease, the person will be a carrier for the disease, but usually will not show symptoms. The risk for two carrier parents to both pass the non-working gene and, therefore, have an affected child is 25% with each pregnancy. The risk to have a child who is a carrier, like the parents, is 50% with each pregnancy. The chance for a child to receive working genes from both parents is 25%. The risk is the same for males and females.
Pendred syndrome affects approximately 2-3 per 1,000 children. This condition is not known to occur more often in people with different racial/ethnic backgrounds.
Hearing loss at birth or during childhood is usually the first sign of this disease. An MRI scan of the inner ear may show an enlarged vestibular aqueduct or an abnormal cochlea. Genetic testing for the pendrin gene is the most common test leading to a diagnosis of Pendred syndrome.
Clinical Testing and Work-up
Abnormal hearing tests lead to the initial suspicion of congenital hearing loss. If possible, an MRI scan of the inner ear may be performed to look for malformations. An MRI does not emit radiation but requires the child to sit still for an extended period. A perchlorate discharge test and thyroid function test may be used to determine how well the thyroid is functioning. The results of these tests will help determine whether the patient needs thyroid hormone supplements or other treatments.
Treatment
There is no specific treatment for Pendred syndrome and supportive therapies are typically aimed at correcting hearing loss and thyroid dysfunction.
Depending on the extent of hearing loss and thyroid dysfunction, patients with Pendred syndrome may need hearing aids, therapy or thyroid supplements. Patients should be very careful to avoid head injuries, since the inner ear is extra sensitive, and some patients have noted worsened hearing impairment or vertigo after minor head trauma.
Information on current clinical trials is posted on the Internet at https://clinicaltrials.gov/ All studies receiving U.S. Government funding, and some supported by private industry, are posted on this government web site.
For information about clinical trials being conducted at the NIH Clinical Center in Bethesda, MD, contact the NIH Patient Recruitment Office:
Tollfree: (800) 411-1222
TTY: (866) 411-1010
Email: [email protected]
Some current clinical trials also are posted on the following page on the NORD website:
https://rarediseases.org/living-with-a-rare-disease/find-clinical-trials/
For information about clinical trials sponsored by private sources, contact:
https://www.centerwatch.com/
For information about clinical trials conducted in Europe, contact:
https://www.clinicaltrialsregister.eu/
Wรฉmeau, J.-L., & Kopp, P. (2017). Pendred syndrome. Best Practice & Research Clinical Endocrinology & Metabolism, 31(2), 213โ224. doi:10.1016/j.beem.2017.04.011
Wall SM, Lazo-Fernandez Y. The role of pendrin in renal physiology. Annu Rev Physiol 2015; 77:363.
Richard Smith. Pendred syndrome. Orphanet. July, 2013; https://www.orpha.net/consor/cgi-bin/OC_Exp.php?lng=en&Expert=705.
Fatemeh Alasti, Guy Van Camp, and Richard JH Smith. Pendred Syndrome/DFNB4. GeneReviews. May 29, 2014; https://www.ncbi.nlm.nih.gov/books/NBK1467/.
Bizhanova, A., & Kopp, P. (2010). Genetics and phenomics of Pendred syndrome. Molecular and Cellular Endocrinology, 322(1-2), 83โ90. doi:10.1016/j.mce.2010.03.006
Pendred syndrome. Genetics Home Reference (GHR). 2008; https://ghr.nlm.nih.gov/condition/pendred-syndrome.
Lado Abeal, J. (2008). Pendred syndrome. Expert Review of Endocrinology & Metabolism, 3(5), 635โ643. doi:10.1586/17446651.3.5.635
Reardon, W. (1997). Pendred syndromeโ100 years of underascertainment? QJM, 90(7), 443โ447. doi:10.1093/qjmed/90.7.443
Muir A, Daneman D, Daneman A, Ehrlich R. Thyroid scanning, ultrasound, and serum thyroglobulin in determining the origin of congenital hypothyroidism. Am J Dis Child 1988; 142:214.
NORD strives to open new assistance programs as funding allows. If we donโt have a program for you now, please continue to check back with us.
NORD and MedicAlert Foundation have teamed up on a new program to provide protection to rare disease patients in emergency situations.
Learn more https://rarediseases.org/patient-assistance-programs/medicalert-assistance-program/Ensuring that patients and caregivers are armed with the tools they need to live their best lives while managing their rare condition is a vital part of NORDโs mission.
Learn more https://rarediseases.org/patient-assistance-programs/rare-disease-educational-support/This first-of-its-kind assistance program is designed for caregivers of a child or adult diagnosed with a rare disorder.
Learn more https://rarediseases.org/patient-assistance-programs/caregiver-respite/The information provided on this page is for informational purposes only. The National Organization for Rare Disorders (NORD) does not endorse the information presented. The content has been gathered in partnership with the MONDO Disease Ontology. Please consult with a healthcare professional for medical advice and treatment.
The Genetic and Rare Diseases Information Center (GARD) has information and resources for patients, caregivers, and families that may be helpful before and after diagnosis of this condition. GARD is a program of the National Center for Advancing Translational Sciences (NCATS), part of the National Institutes of Health (NIH).
View reportOrphanet has a summary about this condition that may include information on the diagnosis, care, and treatment as well as other resources. Some of the information and resources are available in languages other than English. The summary may include medical terms, so we encourage you to share and discuss this information with your doctor. Orphanet is the French National Institute for Health and Medical Research and the Health Programme of the European Union.
View reportOnline Mendelian Inheritance In Man (OMIM) has a summary of published research about this condition and includes references from the medical literature. The summary contains medical and scientific terms, so we encourage you to share and discuss this information with your doctor. OMIM is authored and edited at the McKusick-Nathans Institute of Genetic Medicine, Johns Hopkins University School of Medicine.
View report