Fig. 3

Schematic describes the current diagnostic algorithm for screening ANAs in many labs. IIF using HEp-2 substrates is the first step. Cases that are negative do not need follow up. Positive cases are analyzed for pattern and titer. If disease associated ANA patterns are suspected, respective confirmatory assay/assays are performed. If DFS70/homogenous + speckled mixed pattern is suspected, DFS70 specific confirmatory assays are performed. Both positive and negative DFS70 results on confirmatory assays may warrant additional assays (for autoantibodies towards ENAs, DNA, histone, nucleosome among the others) as presence of disease associated ANAs cannot be ruled out