X-linked Familial Exudative Vitreoretinopathy, Atrophia Bulborum Hereditaria, Andersen-Warburg disea
Monday, 05 April 2004
Last Updated Monday, 05 April 2004
What
Norrie disease is a rare, inherited
genetic disorder that results in progressive blindness, deafness, and mental retardation in children. It presents in several forms ranging from those with mild visual problems to total blindness and deafness in early childhood.
Who
The frequency or
incidence of Norrie disease is not known. There are clusters of families affected throughout the world across all racial groups. The most common inheritance pattern is of the X-linked recessive form, which means only males are affected. Females who inherit one defective copy of the X
chromosome carry the disease but do not have symptoms.
Signs and Symptoms
: Children with Norrie disease manifest the following:
Inability to visually track objects by three months (a sign of decreased vision)
Eye exam shows progressive changes from infiltration of the retina to cataracts to scarred down, sunken appearance of both eyes.
Occasional eye pain from increased pressure within the eyes
Mental retardation and developmental delay, usually relatively mild, but associated with behavioral problems.
Progressive hearing loss beginning in early childhood years.
In severe cases, seizures, delayed puberty, and growth failure can be seen.
Possible Causes
Norrie disease is caused by different
DNA mutations in the NDP
gene localized to
chromosome 11.
Diagnosis
Making the diagnosis of Norrie disease involves recognition of vision problems early in infancy and seeking consultation with an eye doctor for a complete eye exam. Most of the abnormalities can be identified by careful examination by an eye specialist. Your doctor may request a blood sample to send for genetic analysis that can confirm the diagnosis.
Treatment
There is no known cure for Norrie disease. It is important for affected children to be monitored closely for hearing loss and developmental delay. If retinal detachment is only partial at the time of diagnosis, laser therapy or surgical intervention may help some, but will probably not change the ultimate outcome.
Prognosis
Since most children with Norrie disease are born with complete retinal detachment, vision is usually lost by early childhood, but this depends some on the exact type and severity of eye abnormality. While children with Norrie disease do live normal life spans, there are often serious behavioral issues that remain a life-long challenge.
Connect with other parents
In the spirit of community and support, Madisons Foundation offers the unique service of connecting parents of children with rare diseases. If you would like to be connected to other parents of children with this disease,
please fill out this brief form.
Weblinks
Norrie Disease Association
http://neuro-www.mgh.harvard.edu/forum/NorrieDiseaseMenu.html
Norrie Disease center at Massachusetts General Hospital.
Yahoo Health
http://health.groups.yahoo.com/group/norries/
Public forum for families of those with ND to share resources.
Norrie Disease Web Board
http://neuro-mancer.mgh.harvard.edu/cgi-bin/forumdisplay.cgi?action=topics&forum=Norrie+Disease&number=66&DaysPrune=1000&LastLogin=
Another web based public forum for discussions on the disease.
gene Reviews
http://www.geneclinics.org/profiles/norrie/
Thorough synopsis of the inheritance pattern and features of ND.
American Council of the Blind (ACB)
http://www.acb.org/profile.html
Useful information for families with blind children.
American Society for Deaf Children
www.deafchildren.org
Lots of useful resources for families with deaf children.
Google Search for Norrie Disease
References and Sources
Royer, G. et al. (2003) NDP
gene mutations in 14 French families with Norrie disease. Hum Mutat. 22(6):499.
Shastry, B.S. et al. (2003) Overproduction and partial purification of the Norrie disease
gene product, norrin, from a recombinant baculovirus. Biochem Biophys Res Commun 312(1):229-34.