Test Description
Indications of the Cystine Quantitative 24-Hour Urine Test.
This test is indicated for:
- Diagnosis of cystinuria: Elevated levels of cystine in urine confirm the diagnosis.
- Monitoring treatment: Helps assess the effectiveness of therapies aimed at reducing cystine levels and preventing stone formation.
- Evaluation of kidney stone risk: Provides insights into urinary composition that may contribute to nephrolithiasis (kidney stones).
Patient Preparation/Instructions
- Collection Method: A 24-hour urine collection is required. Patients should void at a specific time (e.g., 8 AM), discard that sample, and then collect all urine for the next 24 hours, including the final void at the same time the following day.
- Storage: Keep the urine container refrigerated or at room temperature during collection. After collection, aliquot a sample and freeze it for testing.
- Information Required: The test request must include total urine volume, collection times, and any medications being taken (e.g., penicillamine or tiopronin), as these can affect results.
Typical Reference Values
The typical reference range for cystine in a 24-hour urine sample is approximately 2.1 to 58.0 mg/24 hours. Values outside this range may indicate cystinuria or other metabolic disorders.
Turnaround Time
The expected turnaround time for results is typically 6 days, upon sample collection
Treatment
Management strategies focus on preventing stone formation and include:
- Increased fluid intake: To dilute urine and reduce cystine concentration.
- Urinary alkalinization: using potassium citrate to enhance cystine solubility.
- Medications: such as tiopronin or D-penicillamine, which bind cystine and promote its excretion.
Monitoring for potential side effects from medications is essential, as they can lead to complications like proteinuria.
In cases where stones are present, procedures such as extracorporeal shock wave lithotripsy may be considered.
How To Order This Test In Kenya
To order the Cystine Quantitative 24-Hour Urine Test, please click the ‘Order Test’ button and add it to your cart. Ensure all necessary information is provided for accurate processing and interpretation of results.
