Ignite Creation Date:
2024-05-05 @ 11:22 AM
Last Modification Date:
2024-10-26 @ 9:02 AM
Study NCT ID:
NCT00001166
Status:
COMPLETED
Last Update Posted:
2008-03-04
First Post:
1999-11-03
Brief Title:
Gyrate Atrophy of the Choroid and Retina
Sponsor:
National Eye Institute NEI
Organization:
National Institutes of Health Clinical Center CC
Study Overview
Official Title:
The Diagnosis Pathogenesis and Treatment of Gyrate Atrophy of the Choroid and Retina
Status:
COMPLETED
Status Verified Date:
2004-03
Last Known Status:
None
Delayed Posting:
No
If Stopped, Why?:
Not Stopped
Has Expanded Access:
False
If Expanded Access, NCT#:
N/A
Has Expanded Access, NCT# Status:
N/A
Acronym:
None
Brief Summary:
Gyrate atrophy is a rare hereditary disease of the eyes 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 2000 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
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 2000 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
Detailed Description:
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
1 Document the natural history of gyrate atrophy
2 Relate the clinical course to the gene defect to explore the genetic heterogeneity inherent in this disease
3 Assess the clinical course and laboratory findings of the effects of an arginine-deficient diet The study population is patients with elevated plasma ornithine and absence of ornithine-delta-aminotransferase activity This is a natural history study with a nested intervention study non-randomized with the outcome parameters being psychophysical electrophysiological and ophthalmoscopic examination
1 Document the natural history of gyrate atrophy
2 Relate the clinical course to the gene defect to explore the genetic heterogeneity inherent in this disease
3 Assess the clinical course and laboratory findings of the effects of an arginine-deficient diet The study population is patients with elevated plasma ornithine and absence of ornithine-delta-aminotransferase activity This is a natural history study with a nested intervention study non-randomized with the outcome parameters being psychophysical electrophysiological and ophthalmoscopic examination
Study Oversight
Has Oversight DMC:
None
Is a FDA Regulated Drug?:
None
Is a FDA Regulated Device?:
None
Is an Unapproved Device?:
None
Is a PPSD?:
None
Is a US Export?:
None
Is an FDA AA801 Violation?:
None
Secondary IDs
| Secondary ID | Type | Domain | Link |
|---|---|---|---|
| 78-EI-0001 | None | None | None |