Citrate, urine 24 H Spectrophotometry

The Citrate, Urine 24 hour test measures the concentration of citrate in the urine collected over a 24-hour period.

• • The Citrate, Urine 24 hour test is usually done to assess the risk of calcium stone formation in the kidneys.
  • It is also used to monitor the results of therapy in patients with calcium stones or renal tubular acidosis.

The Citrate, Urine 24 hour test may be recommended in the following situations:

• • When a patient has a history of recurrent calcium kidney stones or a family history of kidney stones.
  • When a patient has symptoms of kidney stones, such as pain in the back or side, blood in the urine, nausea, vomiting, or fever.
  • When a patient has signs of renal tubular acidosis, such as growth failure, bone deformities, muscle weakness, or kidney failure.
  • When a patient is undergoing treatment for calcium stones or renal tubular acidosis with medications or dietary modifications that affect urinary citrate levels.

Low urinary citrate levels (<0.11 mmol/24 hours) may indicate:

• • Increased risk of calcium stone formation
  • Renal tubular acidosis
  • Dietary factors such as high protein intake, low carbohydrate intake, low potassium intake, or high sodium intake
  • Medications such as thiazide diuretics, carbonic anhydrase inhibitors, or corticosteroids
  • Metabolic disorders such as ketoacidosis or lactic acidosis
  • Chronic diarrhea or malabsorption

High urinary citrate levels (>0.46 mmol/24 hours) may indicate:

• • Decreased risk of calcium stone formation
  • Dietary factors such as high carbohydrate intake, high potassium intake, or low sodium intake
  • Medications such as potassium citrate, sodium bicarbonate, or acetazolamide
  • Metabolic disorders such as alkalosis or hypoparathyroidism
  • Pregnancy

The test involves collecting all the urine produced over a 24-hour period in a special container that contains a preservative. Consult your healthcare provider for a detailed process.

Patients may be advised to follow specific instructions before the test, such as:

• • Avoiding foods or beverages that contain citrate, such as citrus fruits, juices, or sodas, for at least 24 hours before and during the collection period.
  • Avoiding alcohol, caffeine, or tobacco for at least 24 hours before and during the collection period.
  • Continuing or discontinuing medications as directed by the healthcare provider.

Additional tests that may be ordered along with the Citrate, Urine 24 hour test include:

• • Calcium, Urine 24 hour: To measure the amount of calcium in the urine and assess the risk of calcium stone formation.
  • Oxalate, Urine 24 hour: To measure the amount of oxalate in the urine and assess the risk of calcium oxalate stone formation.
  • Creatinine, Urine 24 hour: To measure the amount of creatinine in the urine and assess the kidney function and adequacy of urine collection.

• • Citric acid, Urine 24 Hour
  • Urinary citrate test