Response to: ‘Antinuclear antibody as entry criterion for classification of systemic lupus erythematosus: pitfalls and opportunities’ by Bossuyt et al

Antinuclear antibodies by indirect immunofluorescence and solid phase assays

“…Pisetsky et al recently reported substantial variability between two antinuclear antibodies (ANA) indirect immunofluorescence (IIF) assays as well as one solid-phase assay (SPA) from different manufacturers in a study of a cross-sectional cohort of systemic lupus erythematosus (SLE) patients 1. This publication triggered several responses related to the performance of IIF for ANA detection 2–6. Bizzaro questioned whether ANA testing by IIF can be replaced by SPAs for the diagnosis of ANA-associated rheumatic disorders (AARD) 7.…”