Proline/Creatinine Ratio, 24-Hour Urine
Measures urinary proline relative to creatinine in a 24-hour urine collection to help evaluate collagen metabolism.
["This test looks for increased urinary proline, which can occur with some connective-tissue or kidney conditions."]
Key facts at a glance
- LOINC
- 44398-6
- Short code
- Proline/Creat 24h Ur
- Synonyms
- Proline/Creat 24h Ur
- Category
- kidney
- Sample
- urine
- Container
- Sterile urine container
- Units
- N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- Specimen volume
- 10 mL
- Stability
- Room temperature: 2h, Refrigerated: 24h, Frozen: 7d
- Hemolysis max
- 0
- Lipemia max
- 0
- Icterus max
- 0
- TAT
- 4–24 hours
- Order
- routine
What is this test?
This test measures proline, an amino acid linked to collagen formation, in urine collected for 24 hours. The result is compared with urine creatinine to help account for differences in urine concentration.
Why might I need this test?
It may be ordered when a clinician is evaluating possible collagen disorders, joint hypermobility, unusual wound healing, or certain inherited metabolic conditions. It may also help assess how the kidneys are handling proline.
How is the test performed?
You collect all urine into a labeled container for exactly 24 hours. The laboratory then measures proline and creatinine and calculates the proline-to-creatinine ratio.
How do I prepare for the test?
Follow the collection instructions provided by your clinician or laboratory, including any advice about diet, medication use, and storage. Begin and end the collection at the specified times so that all urine from the full 24-hour period is included.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
An elevated proline-to-creatinine ratio may indicate increased collagen breakdown or impaired proline handling, including some inherited connective-tissue disorders and kidney-related conditions. Results can also be affected by collection completeness, kidney function, diet, age, and other factors, so the finding should be interpreted by a clinician in your overall clinical context.
Short name
24-Hour Urine Proline/Creatinine Ratio
Frequently asked questions
Why is a 24-hour urine collection required?
What if I miss part of the urine collection?
Does an abnormal result confirm a specific disorder?
Sources
- 1
- 2Lab Tests OnlineSource
- 3
Click any link to access the full source. PubMed Central (PMC) links provide free full-text access.
This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.
This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.
If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.
Medically reviewed by WellAlly Editorial Team Last reviewed August 16, 2026. · Read our editorial policy