A urine protein-to-creatinine ratio greater than 0.5 indicates what in IRIS guidelines?

• A. Proteinuric
• B. Non-proteinuric
• C. Normal
• D. Indeterminate

Answer: (A)

Proteins in the urine reflect an abnormal leak of protein through the kidneys. The urine protein-to-creatinine ratio (UPC) is used because it accounts for how dilute or concentrated the urine is, giving a more reliable measure of protein loss than a simple protein concentration.

In IRIS guidelines, a UPC above 0.5 is defined as proteinuria, meaning there is significant protein loss in the urine beyond normal levels. This indicates a proteinuric state and often points to renal pathology (such as glomerular injury) that may affect prognosis and guide further investigation and management. Values well below that threshold are generally considered non-proteinuric or borderline, but the important point for this threshold is that a UPC greater than 0.5 denotes proteinuria.