Guided Creatinine Clearance with Urine Collection (24-hour)

Why This Test Is Done

Your doctor may order this test if they suspect kidney disease, poor kidney function, or if you have conditions like high blood pressure, diabetes, or heart disease that can affect kidney health. It’s also used to evaluate kidney function before certain surgeries or treatments.

What to Expect Before the Test

You’ll need to collect all your urine for a full 24-hour period. Typically, you’ll start by emptying your bladder at the beginning of the test and then collect every bit of urine for the next 23 hours. Bring a clean container to store your urine samples. Your doctor or lab technician will guide you through the process to ensure accuracy.

What Happens During the Test

After collecting urine over 24 hours, you’ll provide a sample of your blood to measure creatinine levels. This blood test is usually done at the start or end of your urine collection period. The lab will analyze both samples to calculate your creatinine clearance rate.

What the Results Mean

The results show how efficiently your kidneys filter creatinine from your blood. Lower than expected clearance may indicate kidney problems, while higher values could suggest overhydration or other conditions. Your doctor will interpret these results in the context of your overall health.