Lactate and Creatinine — Urine and Stool Specimens
This test measures lactate and creatinine in urine and/or stool specimens, depending on the laboratory order. The exact sample required should be confirmed before collection.
["Results can reflect changes in metabolism, muscle activity, hydration, and stool composition, so they must be interpreted with the specimen type and your symptoms."]
Key facts at a glance
- LOINC
- 25112-4
- Short code
- Lactate/Creat Ur-sRto
- Synonyms
- 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?
Lactate is a substance produced when cells use energy, while creatinine is a waste product formed as muscles break down creatine. This test may be performed on a urine sample, a stool sample, or both; confirm the exact specimen with the ordering laboratory.
Why might I need this test?
Lactate may be measured when there is concern about impaired energy metabolism or an acid-base disturbance. Creatinine measurement can provide information about muscle activity, hydration, and creatinine production, while interpretation of stool results depends on the specific clinical question.
How is the test performed?
A urine or stool sample is collected in the container supplied by the laboratory and analyzed for lactate and creatinine. Some tests use a timed urine collection, so ask whether a single sample or collection over a specific period is required.
How do I prepare for the test?
Follow the laboratory's collection instructions and label the container with the date and time. Do not fast unless specifically instructed, and ask the laboratory how soon the sample should be delivered and whether refrigeration is required.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
Elevated lactate in the blood can occur when oxygen delivery or use is impaired, but this urine or stool test should not be treated as a direct blood-lactate measurement. Urine creatinine can vary with muscle mass, recent exercise, hydration, and dietary meat intake. Stool measurements are also influenced by diet, bowel activity, and sample handling, so abnormal results require clinical interpretation.
Short name
Lactate and Creatinine
Frequently asked questions
Is this the same as a blood lactate test?
Do I need to fast before this test?
How soon should I submit the sample?
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