Investigaion of antinuclear antibodies with immunological diagnosis methods

The presence of lots of autoantibody has been shown in most of the connective tissue diseases. Antibodies developed against nuclear components found in cell nucleus and/or cytoplasm collected under the title of ANA is very important in the diagnosis of autoimmune diseases such as Rheumatoid arthritis, systemic lupus, erythematosus, Sjögren's Syndrome, dermatomyositis/polidermatomyositis. A total of 191 patients consists of 145 (75.9%) female, 46 (24.1%) male research with preliminary connective tissue disease diagnosis from Internal Medicine, Department of Rheumatology. Anti-nuclear antibodies in serum samples obtained from the patients were investigated with IFA and immunblott methods. ANA positivity was determined in 76 patients (39.8%) and 115 patients (60.2%) were determined as ANA negative with IFA method. Of the patients determined as positive, 28 (36.8) were determined as homogenous, 11 (14.5%) were determined as thin granular, 10 (13.2%) were determined as nucleolar, 8 (10.5) were determined as homogenous/cytoplasmic, 7 (9.2%) were determined as coarse granular, 3 (4.0%) were determined as thin granular/nucleolar, 2 (2.6%) were determined as Jo-1, 2 (2.6%) were determined as anti centromere, 2 (2.6%) were determined as nuclear dot, 1 (1.3%) was determined as nuclear dot/cytoplasmic, 1 (1.3%) was determined as nuclear membrane, 1 (1.3%) was determined as cytoplasmic pattern. One or more subgroups antibodies were determined as negative in 95 (49.7%) patients and negative in 96 (50.3%) with immublott method. When IFA method is considered as gold standard for ANA determination; the sensitivity of immunblott method was found as 77.63%, the specificity was determined as 68.70%, positive predictive value was determined as 62.11%, negative predictive value was determined as 82.29%. As a result, despite lots of the antibodies developed against nuclear and cytoplasmic antigens can be detected with IFA method, well experience is required. Subgroups can be distinguished with immunblott technique. We think that IFA and immublott test should be used in a combination as supplemental tests in laboratories.