SAT0364 Diagnosis of Latent Tuberculosis in Patients Undergoing Biological Therapy

Background Portugal has one of the highest prevalence and incidence of tuberculosis (TB) and latent TB (LTB) in Western Europe 1 . Screening and treatment is performed in Centers for Diagnosis of Chest Pathology (CDP), specifically designated by the Health Authority. Biological Therapy (BT) for Systemic Autoimmune Diseases (SAID) has been associated with an increased reactivation of TB 2 and national 3 and international 4 guidelines recommend LTB screening before therapy onset, a practice that has been followed in our Unit since 2001, when the first patient started BT. The most recent American College of Rheumatology guidelines recommend that patients with negative baseline screening should be re-screened annually 4 . Methods The aim of our study was to capture and treat LTB infections in all patients undergoing current biological treatment for SAID in our Unit. We conducted a prospective study by sending the patients a letter of referral to the CDP, requesting TB re-screening, to be followed by therapy if required. The letter explained to the patient the need for referral and contained clinical information for the CDP. Six months later, medical records were reviewed and patients were contacted telephonically when clinical information was absent or insufficient. Screening intent involved the following: 52 patients with Rheumatoid Arthritis (RA), 26 with Ankylosing Spondylitis (AS), 16 with Psoriatic Arthritis (PA), 4 with Inflammatory Bowel Disease (IBD) and 2 Seronegative Spondyloarthropathies (SS). Demographic characteristics were as follows: RA: F:M=42:10, x age 59 y, x disease duration 12 y; x BT for 4.9 y. AS:F:M=10:16, x age 47 y, x disease duration 11 y, x BT for 5.5 y; PA: F:M=8;8, x age 55 y, x disease duration 14 y, x BT for 6.9 y; IBD: F:M=3:1, x age 47 y, x disease duration 7.5 y and x BT for 3.75 y. The SS group consisted of 2 females; x age 51 y, x disease duration 8.5 y, x BT for 4 y. BT mostly consisted of infliximab, etanercept, adalimumab or tocilizumab; 12 RA patients were on Rituximab on demand. Before BT onset, 14/52 patients with RA, 4/26 with AS and 1/16 with PA had a history of treated tuberculosis. Results Only 36 out of 100 patients were screened at the CDP as a result of our study: 23 received the letter but did not read it, 19 did not receive the letter for several reasons, 3 refused to schedule but 9 promised to schedule the appointment after the telephone contact, 8 already had their follow-up appointment at the CDP within the past year, 1 had a future appointment scheduled and 1 had to suspend the biological agent shortly after receiving the letter. Screening was performed in 9 patients with RA, 18 with AS, 6 with PA, 2 with IBD, 1 in the SS group. Overall, 16 of 36 screened patients required LTB therapy, interrupting BT/the next cycle in the first month of LTB treatment (3 with AR, 10 with AS, 2 with PA and 1 with IBD). Conclusions LTB is an important problem in our patient population under BT. Our study emphasizes the need for systematic re-screening of these patients and the development of more accessible screening mechanisms. References European Centre for Disease Prevention and Control/WHO Regional Office for Europe. Tuberculosis surveillance and monitoring in Europe 2013. Arthritis Rheum. 2003;48:2122-7. Acta Reumatol Port. 2008;33:77-85. Arthritis Care Res 2012;64:625–39. Disclosure of Interest None declared