In the past decade, tumor necrosis factor inhibitors have been used to treat millions of patients with different immune-mediated diseases, demonstrating high levels of efficacy and safety. In various studies, mostly in the field of rheumatology, these agents have been shown to induce positive (33% to 77%) antinuclear antibody (ANA) results; autoimmune diseases have also been reported, primarily lupus, vasculitis, and sarcoidosis.

The article on this topic in the current issue is a retrospective study of a cohort of patients with psoriasis who were treated in a single hospital with adalimumab or etanercept (65 patients in each group). The authors found a relatively large number of patients with positive ANA test result, in line with the findings reported in the literature (12%-37% for etanercept and 25%-50% for adalimumab). The findings of this study are important because they show that, despite the positive ANA test results, none of the patients developed autoimmune connective tissue disease and no association was found between a positive ANA test and the other, possibly autoimmune-related, events reported (paradoxical psoriasis and local reactions, 1 case of urticaria, and 1 of alopecia areata). Other findings relevant to clinical practice are the lack of any association between the appearance of ANA and drug efficacy or between ANA and prior exposure to a biologic agent.

Based on their results and a review of the literature, the authors recommend routine ANA testing and screening for autoimmune diseases before a patient starts biologic therapy, but propose that serial measurement of ANA during follow-up should be limited to patients with suspected autoimmune disease, a strategy that would contribute to the efficiency of the care process.