Investigation of dfs pattern and anti-dfs70 antibody in clinical samples

Investigation of DFS Pattern and Anti-DFS70 Antibody in Clinical Samples ANA is a guide in the diagnosis, follow-up and prognosis of systemic autoimmune rheumatic diseases (SARD). The IIF method is the gold standard method for the identification of ANA and is used for screening purposes. The nature of the antibody against the cell is determined by confirmatory tests. It is recommended that the ANA, including the DFS pattern, should be verified with a highly specific confirmatory test after a sensitive screening test. This approach is called reflex test method. Although methods such as ELISA and LIA are often used to confirm the presence of anti-DFS70 antibodies, new IIF methods have been developed in recent years in order to prevent the difficulties in the recognition of the DFS pattern and to carry out the confirmatory test in a single step. In this study, we compared the CytoBead (Generic Assays, Germany) method with the HEp-2 cell and the Dot with DFS70 antigen, to the routine two-step test strategy. In our study, the samples which were DFS pattern in ANA IIF test in routine practice were studied with LIA test as a confirmatory method. Four hundred seventy nine samples were divided into four groups according to the results of IIF and LIA. They were studied by CytoBead IIF method and 264 among them were studied by ELISA. Only 54.4% of 329 samples with DFS pattern determined by IIF method were found positive by CytoBead HEp-2 test. In 106 samples with IIF (+) LIA (+) ELISA (+), CytoBead HEp-2 + Dot test found 105 (99.1%) positive and gave a very high ratio. Conclusively, both the scanning of DFS pattern the and verification of anti-DFS70 antibody and can be done in one step With the CytoBead IIF method. Thus, it offers a more cost-effective approach. With the development of CytoBead HEp-2 cell substrate it is thought that it will be able to take its place in routine diagnosis in the near future. Key Words: Anti-DFS70, AARD, CytoBead