Background:The development of biologics for the treatment of systemic rheumatic diseases increased the risk of infections. The management of this complication deserves particular attention since it remains a major cause of morbidity and mortality.Objectives:The aim of our study was to determine infection frequency under biological treatment and consequences on the therapeutic management.Methods:Patients included in the Biological National Registry (BINAR) from 2016 to 2020. Data related to the disease, biological agents, and infections occurring under biologic disease-modifying antirheumatic drugs (bDMARDs) were collected.Results:The study included 298 patients with a mean age of 49.2 years [18-79] 175 patients with rheumatoid arthritis and 123 with spondyloarthritis (Axial Spondyloarthritis=48, Enteropathic Arthritis=41, Psoriatic Arthritis=34). Anti Tumor necrosis factor-alpha (Anti-TNF) agents were the most prescribed bDMARDs in 87.9% (n=263) of patients: Infliximab 20.4% (n=61),Etanercept 23.1%(n=69), Adalimumab 24.6%(n=74) and Certolizumab (n=79). No patients were treated with Golimumab. Tocilizumab and Rituximab were prescribed respectively in 10.4% (n=31) and 5% (n=15) of patients. Infections occured in 9 patients (3.1%) with a total of 13 infectious episodes 12 bacterial and a viral one. The site of infections was: respiratory (38%), urinary (15%), cutaneous (23%), ORL (8%), infective endocarditis (8%), and other (8%). The infectious agent was identified in only 3 patients. The outcomes were favorable in most cases except in one patient where there was a definitive interruption of bDMARDs. The patient was hospitalized for sepsis complicating a cutaneous infection with favorable outcomes under antibiotics within a week. The biological agent with higher risk of infections was Tocilizumab (p = 0.056), unlike Rituximab (p = 0.483) and Anti-TNF (p = 0.082). All patients who had an infectious episode were under corticosteroids.Conclusion:Our results confirm that bDMARDs are predisposing to infections, but data from BINAR showed that most infections were trivial with no serious outcomes. Therefore, infections should be assessed in patients under bDMARDs for an early therapeutic intervention.Disclosure of Interests:None declared.