Clinical significance of autoantibodies induced by infliximab treatment: two-year follow-up after infliximab discontinuation.

Infliximab is anti-TNFα monoclonal antibody, which is widely used in the treatment of rheumatoid arthritis (RA) and other inflammatory diseases. Anti-TNFα treatment can induce the occurrence of autoantibodies but in the majority of treated patients, they have no clinical significance although several cases of drug induced lupus have been described. In our cohort of refractory RA patients treated with infliximab for one year, we found a very high number of patients who developed antinuclear autoantibodies (16 of 24 (66.6%) at the time of infliximab discontinuation) and anti-ds-DNA autoantibodies (12 of 24 (50%) at the time of infliximab discontinuation). However, in most of these patients they had no clinical significance. One patient developed clinical and laboratory signs of systemic lupus erythematosus (SLE), which over time became overt as SLE-RA overlapping unmasked by infliximab.