Background The HIV integrase inhibitor raltegravir (RAL) can exacerbate autoimmune diseases in genetically predisposed mice. To evaluate whether this may occur in clinical practice, we clinically monitored HIV-positive patients treated with RAL and measured a panel of autoantibodies (auto-Abs) during the first year of RAL treatment. Methods This was a longitudinal study in 109 antiretroviral-experienced patients who started a RAL-based regimen and were followed up for more than 2 years. A total of 45 patients were tested at baseline (before starting RAL) and after 12 months for the presence of the following auto-Abs: anti-nuclear antibodies, anti-double-stranded DNA, anti-smooth-muscle antibodies, anti-thyreoglobulin and anti-thyroid peroxidase antibodies, anti-cardiolipin immunoglobulin G and immunoglobulin M and anti-nuclear extractable antigens, including anti-SM ribonucleoprotein antigen, anti-Ro antigen and anti-La antigen. Results A low rate of clinically relevant autoimmune diseases was observed at study entry (3/109; 2.8%; 95% CI 0.004, 0.059). No exacerbations were observed during follow-up. During the second year of RAL-based therapy a previously healthy patient developed psoriasis. At baseline, 17/45 (37.8%) patients tested for the presence of auto-Abs were positive. Most patients ( n=13) were positive for anti-cardiolipin. After 12 months of RAL exposure, 9/45 patients were positive (20%; P=0.063). A positive correlation was found between HIV-1 RNA and anti-cardiolipin antibody concentration ( P=0.010). Conclusions According to these results, RAL does not promote antibody-mediated immune disorders, at least not in the mid-term. A prolonged follow-up and an extension of the panel of auto-Abs are recommended to support these results.