Serum or plasma concentration of free immunoglobulin G (IgG) by immunoassay
This test measures the amount of free light chains (the smaller protein parts of immunoglobulin G, or IgG antibodies) in your blood, which can help identify certain immune system conditions or kidney issues.
["Free light chains from IgG antibodies may signal hidden immune disorders or kidney problems."]
Key facts at a glance
- LOINC
- 95708-4
- Short code
- YFV IgA Spec Ql IA
- Synonyms
- YFV IgA Spec Ql IA
- Category
- chemistry
- Sample
- serum
- Container
- Red-top tube (SST)
- Units
- N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- Method
- ia
- 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 recommend this test if you have symptoms like fatigue, unexplained weight loss, or kidney problems, or if they suspect conditions like multiple myeloma, lymphoma, or kidney disease. It can also be part of monitoring for these conditions.
What to Expect Before the Test
No special preparation is needed. You’ll typically provide a blood sample in a clinic or lab. If you’re on blood thinners, let your provider know before the test.
What the Test Results Mean
Results show the concentration of free light chains in your blood. Elevated levels may indicate conditions like multiple myeloma, where abnormal antibody production occurs, or kidney disease. Normal levels usually mean your immune system and kidneys are functioning as expected.
Common Conditions Monitored
This test helps diagnose or monitor conditions such as multiple myeloma, lymphoma, or kidney disorders like light chain amyloidosis. It’s also used to track treatment progress in some cases.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
High levels of free light chains can signal serious conditions like multiple myeloma, where cancerous plasma cells produce abnormal antibodies. Kidney problems, such as light chain amyloidosis, may also cause elevated levels. Low or missing levels are less common but could indicate immune system dysfunction or rare genetic disorders.
Short name
IgG Free Light Chains
Frequently asked questions
What causes abnormal IgG free light chain results?
How often should I get this test?
Can lifestyle changes affect IgG free light chain levels?
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