Urine Dipstick Test Interpretation

Protein/Albumin Dipstick Levels

Standard protein dipstick tests typically report results as: negative, trace, 1+, 2+, 3+, and 4+, corresponding to approximate protein concentrations, according to the American Diabetes Association 1, 2
The protein concentrations are approximately:
- Negative: <10-20 mg/dL, as reported by the American Heart Association 3
- Trace: 20-30 mg/dL, as reported by the American Diabetes Association 4
- 1+: 30-100 mg/dL, as reported by the American Heart Association 5
- 2+: 100-300 mg/dL, as reported by the American Heart Association 6
- 3+: 300-1000 mg/dL, as reported by the American Heart Association 3
- 4+: >1000 mg/dL, according to the European Society of Cardiology 2
For albumin-specific dipsticks, a positive result is typically ≥1+ (≥30 mg/dL), as recommended by the American Diabetes Association 1, 4

Standard dipstick methods for total protein are not sensitive when urine albumin concentration is 20-50 mg/L, as noted by the American Diabetes Association 1, 4
Albumin-specific dipsticks should be used for detecting moderately increased albuminuria, as recommended by the American Diabetes Association 1
Semiquantitative screening tests should be positive in >85% of individuals with moderately increased albuminuria to be useful, according to the American Diabetes Association 1, 4
Practitioners must strictly adhere to manufacturer's instructions when using dipstick tests, as advised by the American Diabetes Association 1, 4
Positive urine albumin screening results by semiquantitative tests should be confirmed by quantitative analysis in an accredited laboratory, as recommended by the American Diabetes Association 1, 4

Positive dipstick results (≥1+, 30 mg/dL) should be confirmed with quantitative testing such as protein/creatinine ratio, as suggested by the American Heart Association 6, 5
The gold standard for proteinuria assessment is a 24-hour urine collection, though spot urine protein/creatinine ratio is more practical, according to the American Heart Association 6, 5
A protein/creatinine ratio ≥30 mg/mmol (0.3 mg/mg) is considered abnormal, as reported by the American Heart Association 6, 5, 3
When neither 24-hour nor protein/creatinine ratio measurements are available, dipstick testing provides reasonable assessment, particularly when values are >1 g/L (2+), as noted by the American Heart Association 6, 5