Serum/plasma free light chains (kappa and lambda) by nephelometry

Why This Test Is Done

Your healthcare provider may order this test to investigate symptoms such as fatigue, bone pain, or unexplained infections. It can also help diagnose or monitor conditions like multiple myeloma, amyloidosis, or other immune-related disorders. Sometimes, it’s used alongside other tests to track treatment progress or detect early signs of disease.

What to Expect Before the Test

No special preparation is needed. You’ll have a small needle inserted into a vein (usually in your arm) to draw blood. The process is quick and usually painless. If you’re on blood thinners or have a hard time with needles, let your provider know.

What the Results Mean

Results show the levels of free kappa and lambda light chains. While normal ranges vary by lab, elevated levels often point to conditions like multiple myeloma or other plasma cell disorders. Your provider will interpret results in the context of your symptoms and other tests.

Common Conditions Monitored

This test is often used to diagnose or monitor multiple myeloma, a cancer of plasma cells, or conditions like amyloidosis, where misfolded proteins build up in tissues. It may also help detect early signs of other immune system disorders.