Significant differences in the analytic concordance between anti-dsDNA IgG antibody assays for the diagnosis of systemic lupus erythematosus-Implications for inter-laboratory testing

Our data show variable degree of concordance between anti-dsDNA IgG ELISAs which may significantly impact inter-laboratory testing as well as the diagnosis and management of SLE patients. Although some of the ELISAs show comparable performance to the CLIFT, the degree of concordance between these assays at high antibody levels suggests that CLIFT is still a relevant confirmatory tool.