Relevance of Systematic Pre-Biologic Infectious Screening in Chronic Inflammatory Rheumatic Diseases: A Retrospective Single-Center Study

Background: Systematic infectious screening is recommended before initiation of biologic therapies in chronic inflammatory rheumatic diseases (CIRDs), yet the clinical impact of this strategy in low-prevalence settings remains insufficiently characterized. This study aimed to evaluate the proportion of abnormal findings and their impact on treatment management. Methods: We conducted a retrospective single-center study including adult patients with CIRDs who underwent systematic pre-biologic infectious screening between January 2019 and June 2025. Screening included HIV, hepatitis B virus (HBV), hepatitis C virus (HCV), interferon-γ release assay (IGRA), and chest radiography. The primary outcome was the proportion of abnormal results and their impact on biologic initiation. Results: A total of 418 patients was included (mean age 48.2 ± 14.6 years; 69.1% female). No active HIV, HBV, or HCV infections were detected. Past HBV infection markers were identified in 2.6% of patients, and anti-HCV antibodies in 0.7%, all without detectable viremia. None of these findings required modification of biologic therapy. IGRA positivity was observed in 4.3% of patients and indeterminate results were seen in 3.1%. Preventive antituberculous therapy was initiated in most newly identified IGRA-positive cases, leading to delayed biologic initiation in several patients. Chest radiography yielded limited additional diagnostic value. Conclusions: In this population, systematic pre-biologic infectious screening identified few clinically actionable viral infections, whereas latent tuberculosis screening represented the main determinant of therapeutic modification. These findings support continued emphasis on tuberculosis risk assessment and warrant further prospective studies to evaluate optimized and potentially targeted screening strategies incorporating cost-effectiveness analyses.