<h3>Background</h3> Biological therapy have revolutionized the treatment of some autoimmune diseases, such as rheumatoid arthritis (RA), and spondyloarthropathies (SpA). Patients receiving biologics have a increased risk of opportunistic infections, particularly of reactivating latent tuberculosis (LTB). <h3>Objectives</h3> To describe the presence of LTB and viral hepatitis in a cohort of patients (pts) with biologic therapy. <h3>Methods</h3> Cross-sectional study. 157 patients of a rheumatology center treated with biological therapy were evaluated. Medical records were reviewed. Variables: sex, mean age, diagnosis, current biological therapy, PPD (&gt;10mm), hepatitis B virus surface antigen reactivity, hepatitis C virus antibody reactivity, chest x-ray, biological therapy since 2001, antinuclear antibodies (ANAS), and associated autoimmunity. Descriptive analysis was done for qualitative and categorical variables (percentages and averages) using STATA11. <h3>Results</h3> In 23 patients (14.7%) was documented LTB. 12 pts (52.2%) are women and 11 pts (47.8%) are male. Mean age: 50,6 y/o. 13 pts (56.5%) have diagnosis of SpA, 9 patients (39,1%) RA, and 1 patient (4.37%) psoriatic arthritis (PsA). 9 pts (39,1%) receive Adalimumab, 7 pts (30,43%) Infliximab, 3 pts (13%) Etanercept, 3 pts (13%) Rituximab, and 1 pt (4,4%) Tocilizumab. Since year 2001, 16 patients (69,6%) have received just one biologic as treatment, 4 pts (17.4%) 3 biologics, 2 pts (8,7%) 2 biologics, and 1 pts (4,3%) 6 biologics. Infliximab is the biologic more prescribed (12 pts, 52,2%) as first choice since 2001. Adalimumab (57,1%) is the one most formulated in the group that have received more tan one biologic. <i>All patients chest X-ray were reported as normal</i>. 14 pts (60.87%) have positive ANAS. Associated autoimmunity: 3 pts (13.4%) uveitis, and 2 pts (8.70%) Sjogren syndrome (SS). Pneumology prescribed all patients Isoniazid for minimun 9 months. The biologic was started o continued after three months on Isoniazid. In 5 patients (3.18%) was documented seropositivity for Hepatitis B (HBV). 3 pts (60%)) are men and 2 pts (40%) are women. Mean age: 56.1 y/o. 4 pts (80%) have diagnosis of RA, and 1 pt (20%) have diagnosis of SpA. 2 pts receive adalimumab (40%), 2 pts Etanercept (40%), and 1 pt Abatacept (20%). Since year 2001, 1 pt (20%) have received 2 biologics, and 1 pt (20%) 4 biologics. Infliximab (40%) and Adalimumab (40%) are the biologic more prescribed. 2 pts (40%) have positive ANAS. Associated autoimmunity: 1 pt (20%) inflammatory bowel disease, and 1 pt (20%) SS. In a 58 y/o female patient with diagnosis of SpA, in treatment with Adalimumab was found seropositivity for Hepatitis C. Associated autoimmunity: Uveitis. All patients were evaluated by gastroenterology. None of these biologic was discontinued. <h3>Conclusions</h3> LBT prevalence in this cohort is higher that reported in other cohorts^1. Adalimumab is the biologic more used in patients with LBT. Normal chest x-ray does not exclude LTB. HBV prevalence is similar to previous data reported.¹The surveillance of LBT and viral hepatitis must be mandatory in patients receiving biological therapy. <h3>References</h3> Nacci F, Matucci-Cerinic M. Tuberculosis and other infections in the anti-tumour necrosis factor-alpha (anti-TNF-α) era. Best Pract Res Clin Rheumatol. 2011 Jun;25(3):375-88. <h3>Disclosure of Interest</h3> None Declared