Detection of M-components by an easy immunofixation procedure: comparison with agarose gel electrophoresis and classical immunoelectrophoresis.

Commercial anti-gamma-alpha-mu and anti-kappa-lambda (mixture of commercial anti-kappa and anti-lambda) were used for immunofixation after agarose gel electrophoresis of 100 serum samples diluted 1 : 5. This simple screening method detected M-components in 39 sera. M-components were detected in 33 sera by agarose gel electrophoresis, and in 30 sera by classical immunoelectrophoresis. More than one band was detected in 15 sera by the screening method, in 3 sera by agarose gel electrophoresis, and in 2 sera by immunoelectrophoresis. The screening method was superior to the combined use of agarose gel electrophoresis and classical immunoelectrophoresis for detection of M-components, and easier to perform and interpret.