Immunoglobulin Free Light Chains, Serum

Casandra

Casandra Test Code MC79531Version 1 (DRAFT)

Performing Lab

Lab Mayo Clinic LabLab Test ID FLCSCPT Code 83521

Immunoglobulin Free Light Chains, Serum

Clinical Use

Use

This test is useful for monitoring patients with monoclonal light chain diseases, such as multiple myeloma, light chain multiple myeloma, and other monoclonal gammopathies. It helps in the detection of free light chains in serum and is particularly beneficial when traditional M-protein is not present in significant concentrations. The test may also assist in the diagnosis of conditions like primary systemic amyloidosis, light chain deposition disease, and non-secretory myeloma, where standard immunofixation results may be negative.

Special Instructions

Ensure proper specimen handling to avoid rejection. If not ordering electronically, complete the relevant test request forms. For non-electronic orders, accompanying requisition forms are necessary for carrying out the test accurately. Refer to specific algorithms for diagnosis and testing procedures associated with amyloidosis and multiple myeloma.

Limitations

Elevated levels of kappa and lambda free light chains may occur due to polyclonal hypergammaglobulinemia or impaired renal clearance. The test is not established for pediatric use, and extreme lipemic samples can interfere with the results. Undetected antigen excess may rarely affect outcomes, and so interpreting results should always consider other laboratory tests and clinical features. Awareness of assay-specific variability is crucial for reducing clinically meaningful misclassification.

Test Details

FDA Approved