Evaluation of antinuclear antibodies by indirect immunofluorescence and line immunoassay methods′: four years′ data from Turkey

The presence of antinuclear antibodies (ANAs), directed against intracellular antigens, is a hallmark of systemic autoimmune rheumatic diseases. The indirect immunofluorescence (IIF) assay is among the most commonly used routine methods for ANA detection as the screening test. The objective of the study was to evaluate ANA patterns in a 4‐year period retrospectively. All 19 996 serum samples that were sent to the Laboratory of Medical Microbiology of the tertiary Hospital by any hospital department between 1 January 2009 and 1 January 2013 with a request to test for ANA, anti‐ENA or both were included in the study. Of these samples, 4375 (21.9%) were ANA‐IIF‐positive and 15621 (78.1%) were ANA‐IIF‐negative. The presented ANA‐positive samples consisted of 2392 (54.67%) homogenous, 818 (18.70%) speckled, 396 (9.05%) centromere, 242 (5.53%) nucleolar, 213 (4.87%) nuclear dots, 178 (4.07%) cytoplasmic (except for actin and golgi), 24 (0.55%) actin, 9 (0.21%) golgi, 53 (1.21%) nuclear membrane and 50 (1.14%) mixed pattern. Totally 7800 samples were examined by LIA. Of these samples, 3440 were positive and 4307 were negative with IIF and LIA. In addition, 22 samples were detected as IIF‐positive but LIA‐negative, whereas the rest 31 samples were IIF‐negative but LIA‐positive. ANA patterns in 22 IIF‐positive samples were homogenous (9), speckled (5), golgi (4), cytoplasmic (3) and nucleolar (1). SSA/Ro‐52, SSB/La and Scl‐70 positivity were detected in 31 IIF‐negative/LIA‐positive samples by LIA. The present study comes forward with its overall scope, which covers 4‐year data obtained in tertiary hospital located in the western part of Turkey.