Serum/plasma free light chains (kappa and lambda) by nephelometry
This test measures the free kappa and lambda light chains found in your blood, which are small protein fragments produced by plasma cells. These fragments can be elevated in conditions affecting plasma cell function.
["Light chains help diagnose and monitor certain blood disorders."]
Key facts at a glance
- LOINC
- 58861-6
- Short code
- GH sp47 SerPl-mCnc
- Synonyms
- GH sp47 SerPl-mCnc
- 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
What Is the Purpose of This Test?
Free light chains are part of the heavy and light chains that make up antibodies. When plasma cells (a type of white blood cell) produce antibodies, they break down into these chains. Normally, most light chains are bound to heavy chains and remain inside plasma cells. However, in certain diseases, free light chains can leak into the bloodstream. Measuring these free light chains helps identify conditions like multiple myeloma, certain lymphomas, or other plasma cell disorders.
Why Might You Need This Test?
Your healthcare provider may order this test if you have symptoms or risk factors for conditions like multiple myeloma (a cancer of plasma cells), amyloidosis (a buildup of abnormal proteins), or other immune system disorders. It can also be used to monitor treatment progress or detect early signs of disease.
How Is the Test Performed?
A blood sample is drawn from a vein in your arm. The blood is then processed to separate the plasma or serum, where the free light chains are measured using a specialized lab technique called nephelometry. This method detects the concentration of kappa and lambda light chains independently.
What Are Common Results and Their Meanings?
Results are typically reported as separate values for kappa and lambda light chains. Elevated levels of either type can indicate an underlying condition affecting plasma cells. However, reference ranges can vary by lab, so your results will be interpreted by your healthcare provider based on your specific situation.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
Elevated free light chains are often associated with plasma cell dyscrasias (disorders of plasma cells), such as multiple myeloma or light chain amyloidosis. These conditions can cause symptoms like fatigue, bone pain, kidney problems, or infections. Monitoring free light chains helps track disease progression and response to treatment. Normal levels usually suggest no significant plasma cell disorder, but further evaluation may still be needed if other symptoms are present.
Short name
Free Light Chains
Frequently asked questions
What Does an Elevated or Low Level Mean?
Can This Test Be Used to Diagnose Multiple Myeloma?
How Often Should This Test Be Done?
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