A Systematic Review and Meta-Analysis of Bacterial Pathogen Prevalence in Acute and Chronic Rhinosinusitis: Implications for Empiric Antibiotic Therapy and Antimicrobial Stewardship

Abstract Objectives To systematically compare the bacterial pathogen profiles of acute rhinosinusitis (ARS) versus chronic rhinosinusitis (CRS). Methods We searched PubMed, Web of Science, and Cochrane Library (1980–2024) for studies reporting sinusitis bacteriology. Fifty-seven studies (16 on ARS, 41 on CRS) met inclusion criteria. Pooled pathogen prevalence was estimated using a random-effects meta-analysis with 95% confidence intervals, with heterogeneity assessed by I² and τ². Results In ARS, the five most prevalent bacteria were methicillin-susceptible Staphylococcus aureus (MSSA, 20.5%), coagulase-negative staphylococci (16.9%), Streptococcus pneumoniae (16.3%), viridans streptococci (13.0%), and Haemophilus influenzae (12.2%). In CRS, coagulase-negative staphylococci were most common (24.3%), followed by MSSA (22.5%), viridans streptococci (12.1%), H. influenzae (11.9%), and S. pneumoniae (9.4%). Notably, MSSA was the single most prevalent ARS isolate, surpassing traditional respiratory pathogens, whereas staphylococcal species (MSSA and coagulase-negative strains) together dominated CRS; pneumococcus was relatively infrequent in CRS. Conclusion ARS and CRS are microbiologically distinct syndromes. ARS infections are now often dominated by S. aureus alongside classical respiratory bacteria, whereas CRS harbors a broader polymicrobial flora with staphylococci predominating and a lower prevalence of S. pneumoniae. These differences underscore the need for distinct clinical management and antibiotic strategies for acute vs. chronic sinusitis.