Correlation of antibody to rheumatoid arthritis associated nuclear antigen and immune complexes to disease activity in patients with rheumatoid arthritis.

Twenty-seven patients with rheumatoid arthritis (RA) maintained on drug regimens were studied monthly for 6-10 months. Disease activity was assessed and levels of anti-RA associated nuclear antigen (RANA) and immune complexes were determined. Anti-RANA generally paralleled disease activity in 64% of cases. Immune complex levels paralleled disease activity in 56% of cases and paralleled anti-RANA in 52% of patients. Immune complexes paralleled anti-RANA together with disease activity in only 33% of patients. Anti-RANA and/or immune complex levels paralleled disease activity indices in 82% of cases. Significant fluctuations (greater than or equal to four-fold) in anti-RANA were frequently found (65%) and were associated with concordant changes in immune complex levels 50% of the time and with changes in disease activity indices 59% of the time. The data suggest that levels of anti-RANA and immune complexes may be important in RA and warrant further investigation.