Cystine Capacity Clinical Study (CysCap)

NCT ID: NCT02120105

Last Updated: 2018-12-03

Basic Information

• Recruitment Status: COMPLETED
• Total Enrollment: 30 participants
• Study Classification: OBSERVATIONAL
• Study Start Date: 2012-09-30
• Study Completion Date: 2017-02-24

Brief Summary

The purpose of this study is to determine whether urinary cystine capacity, an assay used to measure the amount of cystine in the urine, can be used to predict stone recurrence in patients with cystinuria.

Detailed Description

Cystinuria is a rare genetic cause of kidney stones that leads to significant morbidity due to the recurrent nature of the disease. Despite recent advancements in knowledge about cystinuria, such as the discovery of the genetic defects that cause the disease, there have been very few studies of clinical determinants of recurrent stone formation. An optimal method of measuring cystine solubility in the urine has been lacking, and therefore response to pharmacologic and dietary therapy is often not known. Recently, a new assay to measure the amount of cystine in the urine was developed called Cystine Capacity, or CysCap. It is an assay that adds a pre-formed amount of cystine crystals to urine and measures the amount of cystine the urine can take up from the solid phase (in undersaturated urine) or gives up to solid phase (in supersaturated urine). This study seeks to examine how well this measure of urinary cystine predicts stone occurrence, with the ultimate goal of helping to guide therapy and preventing kidney stones in cystinurics.

This is an observational study over 3 years. Subjects who are enrolled in the study will perform semi-annual 24-hour urine collections. They will undergo imaging of the kidneys every 6 months to monitor kidney stone formation or growth, in order to correlate urinary parameters with clinical events. The study will examine how well the urinary cystine capacity predicts stone formation.

Conditions

Cystinuria

Study Design

• Observational Model Type: CASE_ONLY
• Study Time Perspective: PROSPECTIVE

Study Groups

Cystinuria

No interventions assigned to this group

Eligibility Criteria

Inclusion Criteria

• Patients with a confirmed laboratory diagnosis of cystinuria will be included in this study. There will be no age barrier to inclusion, but included patients must be able to reliably collect urine for 24 hours. Men and women will be recruited equally and there are no restrictions for racial or ethnic origin in this study.
• Patient enrollment will require signing of an informed consent document approved by the Lenox Hill IRB.
• For children 8-18 years of age, signing an assent to participate will also be required.

Exclusion Criteria

• Patients will be excluded if they cannot sign consent or assent.
• Furthermore if the patient cannot reliably collect urine for 24 hours or adhere to study follow up visit requirements.

• Minimum Eligible Age: 8 Years
• Maximum Eligible Age: 80 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: No

Sponsors

NYU Langone Health

OTHER

Sponsor Role: lead

Responsible Party

Responsibility Role: SPONSOR

Principal Investigators

David S Goldfarb, MD

Role: PRINCIPAL_INVESTIGATOR

NYU Langone Health

Locations

NYU Langone Medical Center

New York, New York, United States

Countries

United States

References

Goldfarb DS, Coe FL, Asplin JR. Urinary cystine excretion and capacity in patients with cystinuria. Kidney Int. 2006 Mar;69(6):1041-7. doi: 10.1038/sj.ki.5000104.

Reference Type: BACKGROUND

PMID: 16501494 (View on PubMed)

Related Links

http://www.rarekidneystones.org/

Rare Kidney Stone Consortium

Other Identifiers

6402

Identifier Type: -

Identifier Source: org_study_id