Kappa/Lambda Ratio, Serum

Increased kappa free light chains and an increased kappa/lambda ratio may be seen with plasma cell disorders that produce excess monoclonal kappa light chains. Increased lambda free light chains and a decreased kappa/lambda ratio may be seen with plasma cell disorders that produce excess monoclonal lambda light chains.

In the context of MGUS or myeloma, significantly increased free light chain production and a markedly abnormal kappa/lambda ratio indicate an increased risk of disease progression.

Increased free light chains and/or an abnormal serum free kappa/lambda ratio may be seen with people who have some degree of kidney dysfuntion that is unrelated to a plasma cell disorder.

With suspected primary amyloidosis, an increase in serum free light chains with an abnormal kappa/lambda ratio may suggest that amyloidosis is the cause of symptoms. However, a biopsy of affected tissue establishes the diagnosis.

If your results are outside of the normal ranges, you may have a plasma cell disorder.

Free light chains will normally be present in the blood at low levels, with a kappa/lambda ratio of approximately 0.26 to 1.65 for individuals with normal kidney function.

Excess production of free kappa or lambda chains can alter this ratio. Monoclonal free light chains are found in serum of patients with multiple myeloma, Waldenstrom's macroglobulinemia, mu-heavy chain disease, primary amyloidosis, light chain deposition disease, monoclonal gammopathy of undetermined significance, and lymphoproliferative disorders.

When the test is used to monitor a known plasma cell disorder, a decrease in the quantity of excess light chain and a more normal kappa/lambda ratio may indicate a response to treatment.

Decreased free light chains with a normal kappa/lambda ratio may be seen with a disorder that suppresses bone marrow cell production.