Citrate-corrected Calcium (Serum)
This test measures the amount of calcium in your blood after adjusting for the presence of citrate, a substance used to prevent blood from clotting during testing.
["Understanding your calcium levels helps assess bone health and potential blood clotting risks."]
Key facts at a glance
- LOINC
- 79159-0
- Short code
- COLDAGG24
- Synonyms
- CA 24H p inc Titr Ser 4 deg C inc
- Category
- chemistry
- Sample
- serum
- Container
- Red-top serum tube (no anticoagulant); pre-warmed to 37°C prior to collection
- Units
- N/A
- Ref low
- 0
- Ref high
- 1
- Critical range
- — – 1000 N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- Method
- deg-c-incubation
- CPT
- 86157
- SNOMED
- 12101004
- Specimen volume
- 3-5 mL whole blood (minimum 1 mL serum)
- Stability
- Serum should be separated at 37°C and tested promptly; if testing is delayed, serum may be stored at 2-8°C for up to 48 hours; do not freeze
- Hemolysis max
- 500
- Lipemia max
- 1000
- Icterus max
- 500
- TAT
- 24–48 hours
- Order
- routine
Why is this test done?
Your healthcare provider may order this test if you have symptoms like muscle cramps, bone pain, or unusual fatigue. It’s also used to monitor conditions affecting calcium balance, such as kidney disease, vitamin D deficiency, or certain medications.
What does the result mean?
Results are interpreted in the context of your overall health and symptoms. Abnormal levels may indicate issues like low calcium (hypocalcemia) or high calcium (hypercalcemia), which can affect nerves, muscles, or bones.
How is this test performed?
A blood sample is drawn from a vein, typically in your arm. The blood is processed to remove citrate, and the calcium level is measured using a specialized lab technique.
Common conditions affecting calcium levels
Conditions like kidney problems, thyroid disorders, or vitamin D deficiencies can alter calcium levels. Certain medications (e.g., diuretics, antacids) may also influence results.
Reference range
Negative or <1:32 titer at 4°C; titers ≥1:64 are clinically significantN/A
No special patient preparation required. Fasting is not required. Specimen should be collected and maintained at 37°C until serum is separated to prevent cold autoantibodies from being absorbed onto red blood cells in vitro.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
◆Associated findings1
Short name
Cit-Ca
Frequently asked questions
What does citrate correction mean in this test?
Why might my citrate-corrected calcium test be different from my regular calcium test?
Can diet or supplements affect this test?
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