II. Indication
- Proteinuria evaluation and monitoring
- Chronic Kidney Disease diagnosis
III. Efficacy
- More accurate than 24 Hour Urine Protein collection
- Most accurate if first morning void is used
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Urine Albumin to Creatinine Ratio is preferred over Urine Protein to Creatinine Ratio
- Urine Albumin to Creatinine Ratio has higher Test Sensitivity (see below)
- Consider Urine Protein ratio when Urine Albumin to Creatinine Ratio is high (>300 mg/g)
IV. Technique: Random urine collection
- Urine Creatinine in mg
- Urine Protein in mg
- Calculate Urine Protein mg to Urine Creatinine mg Ratio
V. Interpretation: Urine Protein to Urine Creatinine Ratio
- Consider when Urine Albumin to Creatinine Ratio is high (>300 mg/g)
- Lower efficacy than Urine Albumin to Creatinine Ratio
- Lower Test Sensitivity than Urine Albumin to Creatinine Ratio for low level Proteinuria (<150 mg/24 hours)
- Also measures Proteins unrelated to primary Kidney disease (e.g. Multiple Myeloma)
- Child under age 2 years
- Normal Ratio <0.5
- Adults and children over age 2 years
- Normal ratio <0.2 grams Protein per gram Creatinine
- Nephrotic Ratio >3.5 grams Protein per gram Creatinine
- Estimation of total Protein
- Total Protein (g/m2/day) = Upr/Cr * 0.63
- Abitbol (1990) J Pediatr 116(2): 243-7 [PubMed]
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False Positive causes (unrelated to Kidney disease)
- Tubular secreted Proteins (Tamm-Horsfall Protein)
- Plasma Proteins (Multiple Myeloma, Infectious disease)