Lactate and Lactate-to-Creatinine Ratio, Urine/Stool
This test measures lactate in urine or stool and may calculate lactate relative to creatinine, which helps account for differences in sample concentration.
["The result shows how much lactate is present relative to creatinine, but it must be interpreted with your symptoms and other laboratory findings."]
Key facts at a glance
- LOINC
- 79487-5
- Short code
- Lactyl lactate/Creat Ur-sRto
- Synonyms
- Lactyl lactate/Creat Ur-sRto
- Category
- kidney
- Sample
- urine
- Container
- Sterile urine container
- Units
- N/A
- Critical range
- — – 4 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 the amount of lactate in urine or stool. A lactate-to-creatinine ratio may also be calculated to help account for variations in the concentration of the sample.
Why might I need this test?
A clinician may order this test to evaluate lactate levels in urine or stool. The result can provide information about metabolism, intestinal activity, or changes associated with illness, depending on the specimen and clinical situation.
How is the test performed?
A urine or stool sample is collected and analyzed in the laboratory. If a ratio is reported, the laboratory compares the measured lactate amount with the amount of creatinine in the same sample.
How do I prepare for the test?
Follow the collection instructions provided by your healthcare professional. For a urine test, strenuous exercise may temporarily increase lactate, so avoid heavy exercise for the period specified by the laboratory or clinician.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
An elevated lactate result may reflect increased production, reduced clearance, or changes related to exercise, diet, intestinal activity, or illness. In urine, the lactate-to-creatinine ratio can help adjust for urine concentration; in stool, an elevated result may be associated with altered intestinal metabolism or diarrhea. Results should be interpreted with symptoms, medications, specimen type, and other laboratory tests because an abnormal value alone does not establish a diagnosis.
Short name
Lactate and lactate/creatinine ratio
Frequently asked questions
What does a lactate-to-creatinine ratio mean?
Does exercise affect the result?
Does an abnormal result mean I have a serious condition?
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