Diagnostic accuracy of serum protein electrophoresis and free light chain measurements for monoclonal gammopathies

Background: International guidelines suggest a screening panel for monoclonal gammopathies that contains serum protein electrophoresis (SPE), free light chain (FLC) measurements and immunofixation. This combination provides the possibility of a timely accurate diagnosis. Aim: To evaluate the sensibility of a simple screening panel (SPE + FLC). Material and Methods: We analyzed 191 consecutive serum samples of patients with a suspected monoclonal gammopathy (MG). Results: Seventy five patients were diagnosed with MG. The sensitivity and specificity of the combination of SPE + FLC for the diagnosis of monoclonal gammopathy were 95% (95% confidence intervals 89-99) and 99% (95% confidence intervals 96-100), respectively. Conclusions: We were able to validate the international recommendations on the diagnostic accuracy of this simple combination of two tests in serum for monoclonal gammopathy.