Free kappa light chain (serum/plasma)

Why This Test Is Done

Your healthcare provider may order this test if you have symptoms like unexplained fatigue, frequent infections, or kidney problems. It’s also used to monitor conditions like multiple myeloma, lymphoma, or other plasma cell disorders. Sometimes, it’s part of a broader evaluation for autoimmune diseases or certain cancers.

What to Expect Before the Test

No special preparation is needed. You’ll typically provide a blood sample drawn from a vein in your arm. If you’re on blood thinners, let your provider know before the test to avoid unusual bleeding.

What the Results Mean

High levels of free kappa light chains may indicate conditions like multiple myeloma, where abnormal plasma cells produce too many light chains. Low or normal levels usually don’t signal a problem unless part of a broader diagnostic workup. Your results will be interpreted by your healthcare provider in the context of your medical history and other tests.

Common Conditions Monitored

This test is often used to track multiple myeloma, a cancer of plasma cells, or other disorders like Waldenström macroglobulinemia. It may also help diagnose or monitor conditions like chronic lymphocytic leukemia or certain autoimmune diseases.