Creatinine Clearance (Calculated from Serum Creatinine and Estimated Glomerular Filtration Rate)

What Is Creatinine Clearance Used For?

Creatinine clearance helps doctors evaluate kidney health by estimating the volume of blood your kidneys filter each minute. Unlike a single creatinine measurement, this test provides a longer-term view of kidney function, which can help detect early signs of kidney damage or disease.

How Is This Test Performed?

To calculate creatinine clearance, your healthcare provider will typically use a 24-hour urine collection to measure how much creatinine is excreted in your urine. Simultaneously, a blood sample is taken to measure your serum creatinine level. The results are then combined with your height, weight, and other clinical factors to estimate your glomerular filtration rate (GFR).

Why Might You Need This Test?

This test may be recommended if you have symptoms of kidney problems (such as swelling, fatigue, or frequent urination), if you have a condition that affects kidney function (like diabetes or high blood pressure), or if you are taking medications that can impact kidney health. It’s also used to monitor kidney function before and after treatments.

What Are Common Causes of Abnormal Results?

Low creatinine clearance may indicate poor kidney function, while very high levels could suggest conditions like severe dehydration or muscle disorders. Abnormal results often prompt further investigation, such as additional kidney function tests or imaging studies.