Serum or plasma free light chain kappa (immunoassay)
This test measures the amount of free kappa light chains in your blood, which are small protein fragments produced by plasma cells. These fragments can help diagnose conditions like multiple myeloma or other blood disorders.
["Free light chains help detect hidden blood cancers or immune system issues."]
Key facts at a glance
- LOINC
- 17763-4
- Short code
- VZV IgG Ser IF-aCnc
- Synonyms
- VZV IgG Ser IF-aCnc
- Category
- chemistry
- Sample
- serum
- Container
- Red-top tube (SST)
- Units
- N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- Method
- if
- CPT
- 82784
- 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 Might Be Ordered
Your healthcare provider may order this test if you have symptoms like unexplained fatigue, weight loss, frequent infections, or kidney problems. It’s also used to monitor conditions like multiple myeloma, lymphoma, or other plasma cell disorders. Sometimes it’s checked alongside tests for free lambda light chains to get a full picture of your blood’s protein balance.
What to Expect Before the Test
No special preparation is needed. You’ll have a small needle inserted into your arm or vein to draw blood. If you’re taking blood from your own arm, you may need to rest your arm for a few minutes afterward. If you’re concerned about needles, let your healthcare provider know.
What the Results Mean
Results show the concentration of free kappa light chains in your blood. High levels may suggest conditions like multiple myeloma or other plasma cell disorders. Low levels alone aren’t usually concerning unless paired with other tests. Your provider will discuss results in the context of your overall health.
Common Conditions Monitored
This test is often used to diagnose or monitor multiple myeloma, a cancer of plasma cells, or other blood disorders like Waldenström macroglobulinemia. It can also help track treatment progress or detect recurrence.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
Free light chains are normally balanced by kappa and lambda chains. Imbalances can signal hidden blood cancers or immune system issues. High kappa levels alone may not be diagnostic but are often checked alongside lambda light chains to assess for multiple myeloma or other disorders. Your provider may also order this test if you have symptoms like bone pain, kidney problems, or unexplained anemia.
Short name
Free Kappa Light Chain
Frequently asked questions
What causes elevated free kappa light chains?
What if my results are abnormal?
Can I avoid this test if I don’t have symptoms?
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