New automated indirect immunofluorescent antinuclear antibody testing compares well with established manual immunofluorescent screening and titration for antinuclear antibody on HEp-2 cells.

Abstract

The IIF using the HEp-2 cell substrate should be still considered the "gold standard" techniques for determination of antinuclear antibody (ANA). Standardization and automation can be considered to be still in progress. Aim of this study was to evaluate the performance of the commercially automated indirect immunofluorescent antinuclear HEp-2 antibody assay. The study was designed to compare two commercially available HEp-2 ANA by indirect immunofluorescent antibody assays using a sensitivity panel (120 clinically determined patients) and a specificity panel consisting of 78 clinically confirmed negative patients. We compared the NOVA View® system [INOVA Diagnostics San Diego, USA] with the new HELIOS Processor from AESKU Systems/AESKU.Diagnostics (Wendelsheim, Germany) to assess their capability for screening, pattern recognition and titration of the samples. These automated methods were directly compared to manual reading of the same processed slides on respective microscopes and also compared with the known clinical information. The results of the two automated methods were in very good agreement with recognizing negative and positive samples. The HELIOS system detected 188 samples correctly as negative or positive versus 187 detected by the NOVA View® system. The diagnostic sensitivity of the systems was 95.8 versus 96.7% for HELIOS and NOVA View®, respectively. The systems exhibited a diagnostic specificity of 93.5% for the HELIOS system and 91.0% for the NOVA View®. Both systems are suitable for fast and reliable detection of positivity/negativity due to their high sensitivity and will lead to a further increase of standardization in autoimmunity.