Kappa/Lambda Light Chains, Free with Ratio

What this laboratory test evaluates

DetailsKappa/Lambda Light Chains, Free with Ratio – The Kappa/Lambda Light Chains, Free with Ratio, Serum test measures the amount of kappa and lambda free light chains (FLCs) in the blood and calculates the kappa to lambda ratio. It is used to assist in the diagnosis of plasma cell disorders, including multiple myeloma, primary amyloidosis, monoclonal gammopathy of unknown significance (MGUS), Waldenström’s macroglobulinemia, and related disorders. It is also used to monitor disease activity and treatment [1].

Kappa and lambda light chains link with heavy chains to form immunoglobulins. In healthy individuals, most serum light chains are bound to heavy chains. However, excess plasma-cell proliferation associated with plasma-cell disorders can cause an excess of circulating FLCs and increase or decrease the K/L ratio [1].

This test is intended for patients clinically suspected of having hematologic disease, based on certain symptoms and medical conditions. These include bone pain, bone fractures, normocytic anemia, kidney disease, and recurrent infections suggestive of an underlying plasma-cell disorder [1].

Note that blood samples that are grossly hemolyzed or lipemic or contain high levels of circulating immune complexes (CICs) should not be tested, because of the unpredictable degree of nonspecific scatter these sample types may generate.

References
1. AACC. Serum free light chains. https://labtestsonline.org/tests/serum-free-light-chains. Accessed September 3, 2019.

What type of sample is required for this test?2 mL serum

Test ResourcesFor more information, please consult your healthcare provider.

Additional test information

Kappa/Lambda Light Chains, Free with Ratio – This test measures the amount of kappa and lambda free light chains (FLCs) in the blood and calculates the kappa to lambda ratio. It is used to assist in the diagnosis of plasma cell disorders, including multiple myeloma, primary amyloidosis, monoclonal gammopathy of unknown significance (MGUS), Waldenström’s macroglobulinemia, and related disorders. It is also used to monitor disease activity and treatment.

Collection and processing

• Sample type: Serum
• Fasting: No
• Estimated laboratory processing: Results should be available in 2 – 5 business days after the sample is collected

How Sunridge uses laboratory information

Sunridge considers the medical question, symptoms, history, medications, prior results, and whether the finding could change care before recommending testing. A laboratory result is not interpreted in isolation and does not establish a diagnosis by itself.

Before requesting this test

Availability, collection requirements, eligibility, and processing estimates can change. Sunridge reviews each request and, when appropriate, creates the order through Fullscript. Follow the current instructions supplied with the approved order.