Norrie’s Disease: An Overview
Norrie’s Disease (ND) is a rare genetic disorder that affects the development of the eyes and hearing. It is caused by a mutation of the NDP gene and is characterized by blindness at birth, hearing loss, and mental retardation. It is also known as X-linked recessive congenital deafness-blindness syndrome (XLCDB).
The symptoms of Norrie’s Disease usually become apparent within the first few weeks of life. The primary symptom is the complete absence of vision, which is caused by the absence of the retinal photoreceptors. In some cases, the child may also be born with a hearing loss, which is usually moderate to severe. Other symptoms include mental retardation, speech delay, and behavioral issues.
The diagnosis of Norrie’s Disease is made based on the patient’s medical history, physical exam, and genetic testing. Genetic testing for the NDP gene is the most reliable way to diagnose the disorder. An ultrasound or MRI may also be used to confirm the diagnosis.
The treatment of Norrie’s Disease is focused on managing the symptoms and improving quality of life. The lack of vision can be addressed with low vision aids and special education. Hearing loss can be managed with hearing aids or cochlear implants. Mental retardation can be addressed with early intervention and special education.
Norrie’s Disease is a rare disorder that is characterized by complete absence of vision, hearing loss, and mental retardation. It is caused by a mutation of the NDP gene and is most reliably diagnosed by genetic testing. Treatment is focused on managing the symptoms and improving quality of life.
References
Burns, E. R., & Castiglione, C. M. (2017). Norrie Disease. In StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing.
MacDonald, I., & Read, A. P. (2012). Norrie disease: A review. Seminars in Ophthalmology, 27(4), 270–276. https://doi.org/10.3109/08820538.2012.684599
Vannas, A., & Ristolainen, L. (2018). Norrie’s disease. Orphanet Journal of Rare Diseases, 13(1), 18. https://doi.org/10.1186/s13023-018-0720-1