Interpretations

Diagnosis cannot be made and treatment must not be given on the basis of free light chain measurements alone. Clinical history and other laboratory findings must be taken into account.  Elevation of both kappa and lambda free light chains with a normal K/L ratio may occur due to polyclonal hypergammaglobulinemia or impaired renal clearance.

Undetected antigen excess is a rare event but cannot be excluded. If these free light chain results do not agree with other clinical or laboratory findings, or it the sample is from a patient that has had previously demonstrated antigen excess, the result must be checked by retesting at a higher sample dilution. Results should always be interpreted in conjunction with other laboratory tests and clinical evidence; any anomalies should be discussed with the testing laboratory.