Serum/plasma free light chain kappa to lambda ratio (immunoassay)
This test measures the balance between two types of light chains—kappa and lambda—that are released from antibodies in your blood. It helps assess conditions affecting plasma cells, such as multiple myeloma or other B-cell disorders.
["A ratio test to check for imbalances in antibody components that may signal blood disorders."]
Key facts at a glance
- LOINC
- 79174-9
- Short code
- GH 1.5h p chal SerPl-aCnc
- Synonyms
- GH 1.5h p chal SerPl-aCnc
- Category
- chemistry
- Sample
- serum
- Container
- Red-top tube (SST)
- Units
- N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- 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 Is Done
Your healthcare provider may order this test if you have symptoms like unexplained fatigue, frequent infections, or unexplained bone pain. It’s also used to monitor conditions like multiple myeloma, lymphoma, or other blood-related cancers where abnormal antibody production is suspected.
How the Test Works
A small blood sample is drawn, and the light chains (kappa and lambda) are separated and measured using an immunoassay method. The test compares the amounts of these two types to determine the ratio.
What the Results Mean
An abnormal ratio (either too high or too low) may indicate an underlying condition affecting plasma cells. For example, a high ratio could suggest multiple myeloma or other monoclonal gammopathies.
Common Conditions Monitored
This test is often used alongside other blood tests to diagnose or track conditions like multiple myeloma, Waldenström macroglobulinemia, or other B-cell malignancies. It helps confirm or refine diagnoses when symptoms or other lab results suggest abnormal antibody production.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
When plasma cells (a type of white blood cell) become cancerous, they may produce an abnormal amount of light chains instead of normal antibodies. Measuring the kappa-to-lambda ratio helps identify imbalances that may signal conditions like multiple myeloma, where plasma cells proliferate uncontrollably. Early detection is critical for managing these disorders effectively.
Short name
Free Light Chain Ratio
Frequently asked questions
What does an abnormal result mean?
How often should I get this test?
Can diet or lifestyle 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