Platform
Company
Immunology & Autoimmune
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Currently under review
Pending specialist review and validation.
This test measures the total amount of citrate you excrete in your urine over a full 24-hour period. Citrate is a natural compound produced during normal metabolism. In urine, it binds to calcium and helps keep it dissolved, which can reduce the tendency for crystals to form.
Because citrate levels can vary throughout the day, collecting all urine over 24 hours provides a more complete picture than a single spot sample. The test is often performed along with other 24-hour urine measurements, such as calcium, oxalate, uric acid, sodium, and creatinine, to evaluate the environment in which kidney stones can form.
Urinary citrate is a key protective factor against calcium-based kidney stones. Low citrate can make it easier for crystals to come together and grow into stones. Your clinician may order this test if you have had a kidney stone, have a family history of stones, or have conditions that affect acid-base balance. It is also used to assess for issues such as renal tubular acidosis and to understand the overall risk of stone formation.
Results help guide prevention and treatment. If citrate is lower than expected, strategies may include increased fluid intake, dietary adjustments that increase alkali intake, and sometimes prescription alkali such as potassium citrate. If you are already on treatment, the test helps monitor whether therapy is working and informs dose adjustments.
Your citrate result is interpreted together with other 24-hour urine results and clinical context. If your citrate is lower than expected, your clinician may discuss ways to raise it, such as increasing fruits and vegetables, considering citrus-containing foods or beverages if appropriate, reducing excess dietary acid load, and evaluating medications that can help. Sometimes repeating the collection is useful if there is concern about an incomplete or inaccurate sample.
If your citrate is higher than expected, it is often related to diet or alkali therapy and is usually not harmful. Markedly unexpected results can reflect collection issues or medication effects. Always review your numbers with your clinician, who can put them in context with your history, exam, imaging, and other lab results and decide on next steps.
Reference intervals vary by laboratory, analyzer, methodology, population, and units. The ranges shown here are for education only. Always interpret your results against the reference interval printed on your own lab report.
Missing any urine during the 24-hour period or collecting for too long or too short can distort results. Follow timing instructions closely, use the provided container, and keep the jug as instructed, including refrigerating if told to do so.
High animal protein and low fruit and vegetable intake can lower urinary citrate, while higher alkali intake from fruits and vegetables, including citrus foods and beverages, can increase it.
Alkali therapies such as potassium citrate or sodium bicarbonate increase urinary citrate. Carbonic anhydrase inhibitors like topiramate or acetazolamide can lower citrate. Discuss all prescriptions and supplements before testing.
States that increase body acid load, such as chronic diarrhea or metabolic acidosis, tend to lower urinary citrate. Recovery from these conditions or alkali therapy can raise citrate.
Reduced kidney function can alter citrate handling. Bacterial growth in a warm, unpreserved container may consume citrate, so proper storage during collection is important.
Citrate excretion can change with age and may increase during pregnancy. Let your clinician know if you are pregnant or recently postpartum so results are interpreted appropriately.
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