RESUMO
BACKGROUND: The induction of antinuclear antibodies (ANA) and the onset of autoimmune diseases have been reported after treatment with tumor necrosis factor (TNF) inhibitors, though controversy persists. OBJECTIVES: To determine the frequency of onset of autoimmune diseases and of the appearance of autoantibodies in psoriasis patients administered TNF inhibitors (adalimumab and etanercept) subcutaneously and to correlate this with the effectiveness of treatment, adverse effects, and the order of use of TNF inhibitors. We also tried to identify any factors that might predict the appearance of ANA and autimmune diseases. METHODS: We performed a retrospective study of a cohort of 121 patients monitored over an 11-year period. ANA were measured at baseline and at 3, 6, and 12 months; positive results were followed up by study of antibodies to double-stranded DNA. Extractable nuclear antigen (ENA) antibodies were also studied at baseline and at 3, 6, and 12 months. Patients with a baseline assay of ANA and ENA at least one more assay during the first year were included in the study, and these antibodies were measured annually thereafter. Psoriasis area severity index was calculated and adverse effects were recorded at each visit. RESULTS: A significant increase in ANA positivity was observed during treatment of moderate-to-severe psoriasis with adalimumab and etanercept, but this was not associated with the onset of autoimmune diseases. No correlation was observed with treatment efficacy, the order of use of TNF inhibitors, or the appearance of adverse effects. No predictive factors for the appearance of ANA were identified, except for the body mass index. CONCLUSIONS: We recommend ANA measurement and screening for autoimmune diseases prior to treatment with TNF inhibitors, but not routine serial measurements of ANA during follow-up except in patients with signs or symptoms suggestive of autoimmune disease.