Anti-Tumor Necrosis Factor (TNF)-induced lupus (ATIL) is a distinct clinical entity, increasingly recognized in patients with inflammatory bowel disease treated with anti-TNF therapy. Our aims were to evaluate the incidence and clinical and serological markers of ATIL in this population.
This observational cohort study reviewed 454 patient treatment courses with anti-TNF therapy (300 infliximab and 154 adalimumab). A diagnosis of ATIL was based on the most widely accepted diagnostic criteria: (i) a temporal relationship between symptoms and anti-TNF therapy and resolution of symptoms following cessation of the offending medication; (ii) at least one serologic American College of Rheumatology (ACR) criterion of Systemic Lupus Erythematosus (SLE); and (iii) at least one nonserological criterion such as arthritis, serositis, or rash. Clinical, demographic, and serological predictors were evaluated.
The incidence rate of ATIL was 5.7% for infliximab and 0.6% for adalimumab, which are much higher than previously reported postmarketing estimates. The median duration to diagnosis following commencement of anti-TNF therapy was 15 months (3-62 months). ATIL occurs more commonly patients that commence therapy at an older age (46.47 years ± 13.79 years vs. 38.85 years ± 14.75 years, 
ATIL is a significant complication of anti-TNF therapy, affecting 1 in every 20 patients who commence infliximab. A panel of serological markers is useful to confirm the diagnosis and exclude other conditions that may mimic ATIL. Clinicians using anti-TNF medications should counsel patients about this potential risk and monitor for clinical manifestations of lupus during routine follow up.