1. What is Calcium Creatinine Clearance?

Calcium creatinine clearance is a ratio used to evaluate calcium handling by the kidneys. It compares the clearance of calcium to the clearance of creatinine, providing insight into renal calcium excretion and helping to differentiate between various calcium metabolism disorders.

2. How Does the Calculator Work?

The calculator uses the calcium creatinine clearance formula:

Where:

• Urine Ca — Urine calcium concentration (mg/dL)
• Serum Ca — Serum calcium concentration (mg/dL)
• Urine Cr — Urine creatinine concentration (mg/dL)
• Serum Cr — Serum creatinine concentration (mg/dL)

Explanation: This ratio corrects for variations in urine concentration by comparing calcium clearance to creatinine clearance, which is relatively constant.

3. Importance of Calcium Clearance Calculation

Details: Calcium creatinine clearance is important for diagnosing hypercalciuria, differentiating between renal and absorptive hypercalciuria, and evaluating patients with kidney stones or bone diseases.

4. Using the Calculator

Tips: Enter all four values in mg/dL. All values must be valid and greater than zero. Typically, 24-hour urine collections are used for accurate measurement.

5. Frequently Asked Questions (FAQ)

Q1: What is a normal calcium creatinine clearance ratio?
A: Normal values are typically below 0.20. Values above 0.20 may indicate hypercalciuria.

Q2: When is this test typically ordered?
A: This test is often ordered for patients with recurrent kidney stones, suspected hypercalciuria, or calcium metabolism disorders.

Q3: Are there any preparation requirements?
A: Patients should maintain their usual diet and avoid calcium supplements before testing. A 24-hour urine collection is typically required.

Q4: What factors can affect the results?
A: Diet, hydration status, medications, and recent calcium intake can all affect the results. Timing of specimen collection is also important.

Q5: How does this differ from fractional excretion of calcium?
A: While both assess renal calcium handling, fractional excretion of calcium uses a different calculation that includes serum and urine concentrations along with GFR.