Gyrate Atrophy of the Choroid and Retina
|First Received Date ICMJE||November 3, 1999|
|Last Updated Date||March 3, 2008|
|Start Date ICMJE||January 1978|
|Primary Completion Date||Not Provided|
|Current Primary Outcome Measures ICMJE||Not Provided|
|Original Primary Outcome Measures ICMJE||Not Provided|
|Change History||Complete list of historical versions of study NCT00001166 on ClinicalTrials.gov Archive Site|
|Current Secondary Outcome Measures ICMJE||Not Provided|
|Original Secondary Outcome Measures ICMJE||Not Provided|
|Current Other Outcome Measures ICMJE||Not Provided|
|Original Other Outcome Measures ICMJE||Not Provided|
|Brief Title ICMJE||Gyrate Atrophy of the Choroid and Retina|
|Official Title ICMJE||The Diagnosis, Pathogenesis and Treatment of Gyrate Atrophy of the Choroid and Retina|
Gyrate atrophy is a rare hereditary disease of the eye's retina (the layer of light-sensitive tissue that lines the inside of the eyeball) and choroid (a vascular layer of tissue behind the retina). Degeneration of these structures causes near-sightedness, cataracts and progressive loss of vision. This study will examine eye function and chemical and molecular abnormalities in patients with gyrate atrophy to try to better understand, diagnose, and treat the condition. Patients with other degenerative diseases of the choroid and retina, such as retinitis pigmentosa, choroideremia, and others, will also be studied for comparison. Family members of patients will be studied, when possible, to try to identify the genetic basis of the disease and gain information that will aid in genetic counseling.
Study participants will undergo a physical examination and eye examination, including tests of color vision, field of vision, and ability to see in the dark. An electroretinogram and electrooculogram will measure visual cell function. Photographs of the retina will be taken. Blood will be drawn for biochemical study and gene research. Family members who agree to participate in the study will undergo the same eye tests and will also have blood drawn for genetic studies. Patients with gyrate atrophy will also be asked to undergo a small skin biopsy for biochemical and genetic study. They will provide a family history in order to draw a family tree showing how the disease is distributed among family members.
Patients with gyrate atrophy may also participate in studies of the effect of vitamin B6 and diet on blood levels of the amino acid ornithine, which is elevated in patients with gyrate atrophy. Participants will take 500 mg of vitamin B6 by mouth every day for 3 to 6 months. If this study confirms a reduction of ornithine levels, then long-term studies of the vitamin as a possible treatment for the disease may be started.
After the vitamin B6 study, patients will start a nearly protein-free diet to lower ornithine blood levels. More than 2,000 calories are carbohydrate and fat. Some special low-protein foods and limited fruit is included, plus amino acid supplements. Patients who have carefully adhered to this diet have lowered their ornithine levels and slowed disease progression. Patients will be hospitalized for the first 1 to 3 weeks for close monitoring with frequent urine and blood tests. When the blood ornithine level is normalized, a less restricted low protein diet will be prescribed. Participants will have monthly blood tests and a complete eye examination every 6 months to 1 year to evaluate disease progression.
Gyrate atrophy of the choroid and retina (GA) is a rare autosomal recessive chorioretinal degeneration characterized by myopia, cataract, varying degrees of night blindness, and progressive constriction of visual fields associated with chorioretinal atrophy resulting in blindness. The objectives of this protocol are threefold:
|Study Type ICMJE||Observational|
|Study Design ICMJE||Not Provided|
|Target Follow-Up Duration||Not Provided|
|Sampling Method||Not Provided|
|Study Population||Not Provided|
|Condition ICMJE||Gyrate Atrophy|
|Intervention ICMJE||Not Provided|
|Study Group/Cohort (s)||Not Provided|
* Includes publications given by the data provider as well as publications identified by ClinicalTrials.gov Identifier (NCT Number) in Medline.
|Recruitment Status ICMJE||Completed|
|Completion Date||March 2004|
|Primary Completion Date||Not Provided|
|Eligibility Criteria ICMJE||
Patients must have hyperornithemia and a deficiency of OAT activity to enter the study.
|Accepts Healthy Volunteers||No|
|Contacts ICMJE||Contact information is only displayed when the study is recruiting subjects|
|Location Countries ICMJE||United States|
|NCT Number ICMJE||NCT00001166|
|Other Study ID Numbers ICMJE||780001, 78-EI-0001|
|Has Data Monitoring Committee||Not Provided|
|Responsible Party||Not Provided|
|Study Sponsor ICMJE||National Eye Institute (NEI)|
|Collaborators ICMJE||Not Provided|
|Investigators ICMJE||Not Provided|
|Information Provided By||National Institutes of Health Clinical Center (CC)|
|Verification Date||March 2004|
ICMJE Data element required by the International Committee of Medical Journal Editors and the World Health Organization ICTRP