Interpretation
| Result | Meaning |
|---|---|
| < 0.15 g/g (< 15 mg/mmol) | Normal–mild |
| 0.15–0.5 g/g (15–50 mg/mmol) | Moderate |
| > 0.5 g/g (> 50 mg/mmol) | Severe |
| ≥ 3.5 g/g | Nephrotic range |
Formula
UPCR (mg/mg) = urine protein (mg/dL) ÷ urine creatinine (mg/dL) ≈ g protein/day. 1 g/g = 1000 mg/g = 113 mg/mmol. SI: protein (g/L) × 1000 ÷ creatinine (mmol/L) = mg/mmol.
Clinical pearls
- The g/day estimate assumes ~1 g/day creatinine excretion; it overestimates in muscular people and underestimates in frail or sarcopenic patients.
- For CKD staging and KFRE, urine albumin:creatinine ratio is preferred over protein:creatinine.
Examples
upcr urine protein 50 mg/dL urine creatinine 100 mg/dLprotein creatinine ratio urine protein 0.8 g/L urine creatinine 6 mmol/Lspot urine protein 400 creatinine 100: nephrotic?
FAQ
How do you convert a protein:creatinine ratio to 24-hour protein?
A UPCR in mg/mg (g/g) approximates grams of protein per day; in mg/mmol divide by about 113 (often approximated as ÷100).
What UPCR is nephrotic range?
About 3.5 g/g (≈ 350–400 mg/mmol) or higher.