Serum Lambda Light Chain Immunoglobulin (Free Light Chain) Profile
This test measures the levels of free lambda light chains in your blood, which are small protein fragments produced by plasma cells. These fragments can help identify conditions affecting plasma cell function or multiple myeloma.
["Assessing free light chain levels helps diagnose and monitor certain blood disorders."]
Key facts at a glance
- LOINC
- 104322-3
- Short code
- Lymphs Lambda/lymph NFr Mar
- Synonyms
- Lymphs Lambda/lymph NFr Mar
- 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, weight loss, frequent infections, or bone pain. It may also be used to monitor conditions such as multiple myeloma, lymphoma, or other plasma cell disorders. Sometimes, it’s part of a broader evaluation for kidney function or other blood-related issues.
How the Test Works
A small blood sample is drawn from your arm. The lab separates the serum (liquid part of blood) and measures the concentration of free lambda light chains using an immunoassay method, which detects these protein fragments with high sensitivity.
Sample Collection and Preparation
You’ll typically fast before the test, but this isn’t always required. The blood sample is sent to a lab where it’s processed to isolate serum. The test doesn’t require special preparation beyond standard blood draw instructions.
What to Expect After the Test
You may feel slight discomfort or bruising at the injection site, but most people recover quickly. Results are usually available within a few days, depending on lab processing times. Follow-up may include additional tests or consultations if needed.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
Elevated levels of free lambda light chains can indicate conditions such as multiple myeloma, where abnormal plasma cells produce too many light chains. High levels may also signal other disorders like lymphoma or kidney disease. Low or normal levels usually don’t raise concerns unless part of a broader diagnostic workup.
Short name
Free Light Chain Test
Frequently asked questions
What does an abnormal result mean?
How often should I get this test?
Can lifestyle changes 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