SAT0057 The Conversion Rate of Tubercolosis Screening Tests During Biological Therapies in Patients with Rheumatoid Arthritis

BackgroundScreening for active tubercolosis (TB) and latent TB and latent TB infection (LTBI) is mandatory to the initiation of any biological therapy in patients with rheumatoid arthritis (RA) or spondylarthritis. Hatzara et al (1), have recently reported the rate of TB screening test conversion during anti-tumor necrosis factor (anti-TNF) therapy in rheumatic patients with negative baseline screening. No data are available on the topic in rheumatic patients undergoing biological treatment with different drugs.ObjectivesTo investigate the rate of TB test conversion in RA patients undergoing distinct biological therapies: anti-TNF, tocilizumab, abatacept.MethodsFiles from 190 RA patients treated with different biological agents were retrospectively analysed. Patients with negative baseline TB screening (tuberculin skin test: <5 mm –TST and quantiferon TB gold in tube –QFT-GIT; chest x-ray) and with re-screening for TB assay 1 year later were considered.ResultsOne hundred and sixty-five patients (mean age 55.3±9.8; median 55 years, range: 28-78; 148 female) with TB screening negative at baseline were investigated. One hundred and twelve (67.9%) patients had been treated with an anti-TNF agent (38 with adalimumab; 16 with certolizumab pegol; 35 with etanercept; 18 with golimumab; 5 with infliximab), 25 (15.1%) with abatacept and 28 (17%) patients with tocilizumab. After 12 months, 43 patients (26%) displayed a conversion of at least one screening assay (conversion of TST and/or QFT-GIT). Out of them, 1 patient had been treated with abatacept, 1 with tocilizumab and 41 with an anti-TNF agent. The incidence of TB test conversion was significantky lower in RA patients treated with abatacept or tocilizumab with respect to that detected in RA patients treated with TNF inhibitors (log rank test p<0.0001). Nevertheless, no patient developed an active TB.ConclusionsThe present study points out a lower incidence of TB test conversion in patients treated with either abatacept or tocilizumab with respect to those treated with any anti-TNF α agent.ReferencesHatzara C. et al; Ann Rheum Dis, 2014.Disclosure of InterestNone declared