Urinary Protein-to-Creatinine Ratio (Protein:Creatinine Ratio, PCR)

Why This Test Matters

Your kidneys filter waste and extra fluid from your blood. Protein in urine can signal kidney strain, especially if it appears with high creatinine levels. This ratio helps identify kidney issues before symptoms develop, such as chronic kidney disease or early diabetic nephropathy.

How the Test Works

A small urine sample is collected (often first-morning urine) and tested for protein and creatinine levels. The ratio compares protein concentration (mass concentration) to creatinine concentration, providing a standardized way to evaluate kidney function without relying on blood tests alone.

When You Might Need It

Your doctor may order this test if you have risk factors for kidney problems (e.g., diabetes, high blood pressure, family history), symptoms like frequent urination, swelling, or fatigue, or if you’re undergoing treatment for conditions that affect kidneys.

Sample Collection

You’ll collect a clean-catch urine sample (or a catheter sample if needed) in a sterile container. First, wash your hands and gently clean the urinary opening. Start urinating into the toilet, then collect the middle portion of your urine in the container. Stop once the flow slows. Avoid using soaps or perfumes near the opening.