The Role of Susceptibility to Thrombosis in the Pseudotumor Cerebri of Nephropathic Cystinosis: A Case-Control Study
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|ClinicalTrials.gov Identifier: NCT00071903|
Recruitment Status : Completed
First Posted : November 4, 2003
Last Update Posted : July 2, 2017
|First Submitted Date||November 3, 2003|
|First Posted Date||November 4, 2003|
|Last Update Posted Date||July 2, 2017|
|Study Start Date||October 30, 2003|
|Primary Completion Date||Not Provided|
|Current Primary Outcome Measures||Not Provided|
|Original Primary Outcome Measures||Not Provided|
|Change History||Complete list of historical versions of study NCT00071903 on ClinicalTrials.gov Archive Site|
|Current Secondary Outcome Measures||Not Provided|
|Original Secondary Outcome Measures||Not Provided|
|Current Other Outcome Measures||Not Provided|
|Original Other Outcome Measures||Not Provided|
|Brief Title||The Role of Susceptibility to Thrombosis in the Pseudotumor Cerebri of Nephropathic Cystinosis: A Case-Control Study|
|Official Title||The Role of Susceptibility to Thrombosis in the Pseudotumor Cerebri of Nephropathic Cystinosis: A Case-Control Study|
This study will examine whether the tendency to have thrombosis, or the formation of blood clots inside blood vessels, has a role in the development of pseudotumor cerebri (PTC). PTC causes symptoms and signs of isolated elevated blood pressure in the cranium, or covering of the brain. The disorder can lead to significant, negative effects on the visual system. Increased pressure of the cerebrospinal fluid, that is, fluid around the brain, is a factor, but the cause of the disorder is not clear. There has been documentation of clustering of PTC within families. It suggests that potential genetic polymorphisms-abilities to take on different forms-may become evident after exposure to conditions known to trigger PTC.
Thrombosis comes about by interactions between genetic and environmental or acquired factors, or both, resulting in a blood clot at a specific time and location. Because the disease occurs in episodes, the interaction of the genetic and nongenetic risk factors is important. Cystinosis is a recessive disorder caused by deposits of cystine within the lysosomes of cells-that is, sac-like cell parts that contain various enzymes. Involvement of the kidneys remains the primary characteristic, eventually leading to renal failure. Of all of the risk factors that make it easier for blood clotting, a high level of a substance called homocysteine is of particular interest. Too much homocysteine in blood plasma is a common finding in patients with kidney failure, and it has been recently identified as an independent risk factor for diseases of the blood vessels.
Participants of all ages who meet the Dandy criteria for PTC may be eligible for this study. Pregnant women will be excluded. There will also be a control group of nephropathic cystinosis patients who do not have PTC.
Participants will be asked to undergo the following tests and procedures:
The evaluation of patients will generally last 3 to 4 days. For the collection of cerebrospinal fluid, the patient's skin on the back will be numbed with a local anesthetic. A special needle will be inserted into the back, and a small amount of the fluid will be drawn through the needle. There will be pain for a minute, although there can be a headache lasting 24 hours. Also, there may be bruising, local pain, bleeding, or infection where the needle enters. Patients may also have a magnetic resonance imaging scan of their head. During the MRI scan, patients will lie still on a table that slides in and out of a metal cylinder surrounded by a strong magnetic field. Patients will be able to communicate with the MRI staff at all times and may ask to be moved out of the machine at any time.
During the follow-up of cystinosis patients under protocol #78-HG-0093 "Use of Cysteamine in the Treatment of Cystinosis", we found that 6 of our NIH patients developed papilledema and were diagnosed with pseudotumor cerebri (PTC), whose occurrence has not been previously reported in cystinosis. The goal of this protocol is to identify the role of thrombosis susceptibility in the development of PTC in nephropathic cystinosis patients in view of our recent findings regarding genetic susceptibility to thrombosis in PTC in general. We propose a case-control study. A total of 9 nephropathic cystinosis patients who developed PTC and 9 control nephropathic cystinosis patients without PTC will be screened based upon a thrombosis susceptibility screening panel, including total homocysteine, protein C and S, antithrombin III, fibrinogen, Factor VIII, Factor IX, Factor XI levels, testing for PT, PTT, activated protein C resistance, antiphospholipid antibodies (ACA panel and Lupus AC) and screening for FV Leiden mutation, FV G1628A polymorphism, FV R2 allele, Prothrombin 20210 mutation and 5,10-methylenetetrahydrofolate reductase (MTHFR) gene C677T polymorphism in patients with severe homocysteinemia (greater than or equal to 100 micro mol/l).
We will compare the prevalence of the factors that lead to thrombosis susceptibility in the cases and controls.
|Study Design||Not Provided|
|Target Follow-Up Duration||Not Provided|
|Sampling Method||Not Provided|
|Study Population||Not Provided|
|Study Groups/Cohorts||Not Provided|
* Includes publications given by the data provider as well as publications identified by ClinicalTrials.gov Identifier (NCT Number) in Medline.
|Original Enrollment||Same as current|
|Study Completion Date||July 18, 2008|
|Primary Completion Date||Not Provided|
The inclusion criteria include only a confirmed diagnosis of pseudotumor cerebri (past or present) in a patient with nephropathic cystinosis. Patients will be diagnosed as having pseudotumor cerebri based upon modified Dandy criteria:
Nephropathic cystinosis patients of all ages who meet the Dandy criteria for PTC will be considered for the study.
Pregnant patients will be excluded from the study.
|Ages||2 Years to 50 Years (Child, Adult)|
|Accepts Healthy Volunteers||No|
|Contacts||Contact information is only displayed when the study is recruiting subjects|
|Listed Location Countries||United States|
|Removed Location Countries|
|Other Study ID Numbers||040010
|Has Data Monitoring Committee||Not Provided|
|U.S. FDA-regulated Product||Not Provided|
|IPD Sharing Statement||Not Provided|
|Responsible Party||Not Provided|
|Study Sponsor||Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD)|
|PRS Account||National Institutes of Health Clinical Center (CC)|
|Verification Date||July 18, 2008|