Interferencias por terapia con anticuerpos monoclonales en electroforesis e inmunofijación de proteínas séricas

The electrophoresis was positive for high drug concentrations in the three monoclonal antibody groups, being the signals weaker with decreasing concentrations. Same result was obtained with immunofixation, noting a band corresponding to a kappa G immunoglobulin which migrates closer to the cathode for the cases of rituximab and tocilizumab than for infliximab. It has been proved that rituximab, infliximab and tocilizumab are detected by agarose gel electrophoresis and their corresponding immunofixations and may cause false positives while detecting monoclonal components. Professionals should know the electrophoresis and immunofixation patterns of the monoclonal antibody drug used in their workplaces in order to avoid reporting false positives.