Creatinine Clearance, Serum and 24-Hour Urine

Casandra

Casandra Test Code MC24356Version 1 (DRAFT)

Performing Lab

Lab Mayo Clinic LabLab Test ID CRCLCPT Code 82575

Creatinine Clearance, Serum and 24-Hour Urine

Clinical Use

Use

The Creatinine Clearance test measures the efficiency of the kidneys in filtering creatinine, which can be used to estimate the glomerular filtration rate (GFR). This test is useful for diagnosing and monitoring kidney function and is particularly important for patients with risk factors for chronic kidney disease such as diabetes, hypertension, cardiovascular disease, or a family history of kidney disease. The estimated GFR is calculated using the CKD-EPI equation which does not require adjustments for weight, height, or race, making it widely applicable.

Special Instructions

Not provided.

Limitations

Creatinine clearance may overestimate true glomerular filtration rate (GFR) by 10% to 15% due to proximal tubular secretion of creatinine. Accuracy is highly dependent on complete and accurately timed urine collection. Results can be skewed in patients with elevated levels of certain substances, such as N-acetyl-p-benzoquinone imine (a metabolite of acetaminophen), N-acetylcysteine, and metamizole.

Test Details

FDA Approved