DOI: 10.36347/sjams.2017.v05i07.008

Pages: 2520-2526

Detection of antinuclear antibody (ANA) is one of the diagnostic criterias for autoimmune rheumatic diseases (ARD). Both indirect immunofluorescence (IIF) and line immunoassay (LIA)methods are useful for this purpose. However, there are lack of comprehensive data comparing these two methods in autoimmune diseases in Indian population. The aim of this study was to compare the ANA IIF patterns with LIA serum antibodies and to find a definite correlation between the these two methods.A total 662 serum samples of patients from a random east Indian population at a tertiary are institute suspected for rheumatic diseases were subjected for ANA testing by indirect immunofluorescence method and/or line immunoassay during the prospective cross sectional study period of 12 months. Out of 662 samples received, only 394 cases were analyzed for both ANA by IIF method and line immunoassay. Among these 138 (35.02%) were ANA-IIF positive and 114 (82.6%) were also line immunoassay positive. The homogenous pattern was the most common(n=60;52.6%) ANA pattern. The second most common was the speckled (n = 46; 40.3%) pattern. Different combinations of specific autoantibodies were observed in association with these ANA patterns. In our study, 24(17.3%) of the ANA-IIF positive samples showed negativity with line immunoassay. ANA-IIF negativity was observed in 256 of the total 394 samples under study. Of these, 38(14.8%) exhibited positivity with line immunoassay. 218 samples were negative for both ANA and line immunoassay. The fluorescence patterns of ANA IIF can predict the presence of certain specific antibodies in the sera detectable by LIA . These correlations are of relevance for the diagnosis of a specific rheumatic disease and help in avoiding costly investigative procedures unless needed.