24-Hour Serum Creatinine Clearance (or Renal Inulin Clearance)

Why This Test Is Done

Your doctor may order this test to evaluate kidney function, diagnose kidney disease, or monitor kidney health in people with conditions like diabetes, high blood pressure, or chronic kidney disease. It helps determine how effectively your kidneys are removing waste and excess fluids from your blood.

What to Expect Before the Test

You’ll need to collect a 24-hour urine sample starting from one point in the morning until the same time the next day. You’ll also provide a blood sample. Follow your doctor’s instructions carefully to ensure accurate results, including proper timing and sample handling.

How the Test Works

Inulin, a harmless sugar-like substance, is introduced into your body. Your kidneys filter it out into your urine. By measuring the amount of inulin in your urine and blood over 24 hours, doctors calculate how well your kidneys are working to remove waste.

Possible Results and Interpretation

Results are typically expressed as a clearance rate (e.g., milliliters per minute or liters per minute). Lower than expected clearance may indicate kidney damage or disease, while higher values may suggest overfiltering or other conditions. Your doctor will interpret results in relation to your overall health.