Plasma/Serum Creatinine with Immunoassay Method
This test measures the level of creatinine, a waste product from muscle metabolism that your kidneys filter out of your blood. High levels may indicate kidney function issues.
["Creatinine helps assess how well your kidneys are working by checking waste removal efficiency."]
Key facts at a glance
- LOINC
- 53145-9
- Short code
- LH 45M p chal SerPl-aCnc
- Synonyms
- LH 45M p chal SerPl-aCnc
- Category
- chemistry
- Sample
- serum
- Container
- Red-top tube (SST)
- Units
- N/A
- Ref low
- 1.5
- Ref high
- 9
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- CPT
- 83002
- 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 key marker for kidney health because it reflects how effectively your kidneys filter blood. Your kidneys normally remove creatinine from your blood, and if they’re not working well, creatinine levels can build up in your bloodstream. This test helps doctors monitor kidney function, especially in people with symptoms like fatigue, swelling, or changes in urine output.
What to Expect Before the Test
No special preparation is needed for this test. You may have a small needle inserted into your arm or a blood sample collected from a finger prick. If you’re having a urine test (unlikely here), you might need to collect a sample over 24 hours. Avoiding certain medications or foods for a short time may be advised by your doctor, but this test doesn’t require strict dietary restrictions.
What the Results Mean
Results are typically compared to a reference range that varies by lab and individual factors like age, sex, and muscle mass. Higher-than-normal levels may signal kidney problems, while very low levels could indicate muscle disorders or liver disease. Your doctor will discuss your specific results in the context of your overall health.
Common Causes of Abnormal Results
Elevated creatinine levels may be caused by kidney disease, dehydration, severe muscle injury, or certain medications. Low levels might be linked to muscle wasting, liver disease, or overhydration. Conditions like diabetes or heart failure can also affect kidney function and creatinine levels.
Reference range
Follicular: 1.5-9.0 mIU/mLN/A
For females: inform if menstrual cycle status. For certain tests, timing within menstrual cycle may matter.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
◆Associated findings1
Short name
Creatinine (Serum/Plasma)
Frequently asked questions
How often do I need this test?
What if my results are out of the normal range?
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 16, 2026. · Read our editorial policy