Scientific Journal of

  Abstract

 Background and Objectives

  Rheumatoid arthritis (RA) is a severe chronic inflammatory disease that can not be easily rapidly treated. It can cause joint destruction and disability. Generally some laboratory tests, such as Rheumatoid Factor (RF), Erythrocyte Sedimentation Rate (ESR) or C-Reactive Protein (CRP) can be used for diagnosi s and monitoring of the rheumatoid arthritis. However, they are not always ideal. In inflammatory diseases such as rheumatoid arthritis, the level of IgA will increase in serum the surplus IgA can then react with some of the serum proteins such as Alpha-1-antirypsin ( a ₁ AT) to form a non-immune complex. The complex IgA – a ₁ AT is formed by disulfide bonding between an active thiol group available on the both proteins. Some reports suggested that this complex is a good marker for RA disease without false results, while RF test has some false negative results.

  Materials and Methods 

 In this study the level of IgA- a ₁AT complex in thirty seven RA patients and in forty four normal subjects by ELISA methods using anti- a ₁-antirypsin monoclonal and anti-IgA polyclonal HRP conjugated antibodies was evaluated. Routine laboratory tests of RF, CRP and ESR in patients and controls were also investigated.

 Results

 Our results showed that IgA- a ₁AT complex level in patients (43.7 ± 15.4) is significantly higher than controls (21.5 ± 8.3) (p<0.05). There were significant differences between the sera complex levels in patients and controls. The RF results revealed eleven false negatives (30%) while the level of complex had only one false result (3%).

 Conclusions

 Instead of RF, a rapid and sensitive ELISA test for IgA- a ₁AT complex level in RA patients is strongly recommended.

 Key words: IgA- a ₁AT complex, ELISA, Rheumatoid arthritis