Serum Creatinine Concentration (Mass Concentration)
This test measures the amount of creatinine, a waste product from muscle metabolism, in your blood serum. It helps assess kidney function.
["A creatinine test helps doctors check how well your kidneys are filtering waste from your blood."]
Key facts at a glance
- LOINC
- 102454-6
- Short code
- M racemosus IgE RAST
- Synonyms
- M racemosus IgE RAST
- Category
- chemistry
- Sample
- serum
- Container
- Red-top tube (SST)
- Units
- N/A
- Ref low
- 10
- Ref high
- 40
- Critical range
- — – 500 N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- Method
- rast
- CPT
- 84484
- SNOMED
- 302774002
- Specimen volume
- 5 mL
- Stability
- Room temperature: 4h, Refrigerated: 24h, Frozen: 7d
- Hemolysis max
- 500
- Lipemia max
- 1000
- Icterus max
- 500
- TAT
- 4–24 hours
- Order
- routine
Why This Test Matters
Creatinine is a byproduct of muscle breakdown and is filtered out by your kidneys. High levels can indicate reduced kidney function or damage, while low levels may suggest overhydration or other conditions. This test is often used alongside other measures like blood urea nitrogen (BUN) to evaluate kidney health.
What to Expect Before the Test
No special preparation is usually needed, but you may be asked to fast for 8–12 hours before the test if it’s part of a broader metabolic panel. Drink plenty of water the day before to ensure accurate results. Avoid heavy exercise or extreme dehydration, as these can affect creatinine levels.
What the Results Mean
Results are typically reported in milligrams per deciliter (mg/dL) or millimoles per liter (mmol/L). While reference ranges vary by lab, consistently high or low values may signal kidney issues, dehydration, or other health concerns that require further evaluation.
Common Causes of Abnormal Results
Elevated creatinine levels may occur due to kidney disease, dehydration, severe muscle damage, or conditions like heart failure. Low levels can result from overhydration, liver disease, or certain medications. Always discuss results with your healthcare provider.
Reference range
Adult: 10-40 U/LN/A
No special preparation required. Avoid fatty meals before the test if possible.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
This test is critical for monitoring kidney function, diagnosing conditions like chronic kidney disease, and guiding treatment plans for patients with diabetes, hypertension, or other chronic illnesses. It’s also used in pre-surgery evaluations to assess overall health.
Short name
Creatinine
Frequently asked questions
What triggers a creatinine test?
How long does it take to get results?
Can diet or exercise affect creatinine levels?
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 17, 2026. · Read our editorial policy