Clinical Report: Prevalence of Bacterial Pathogens in Rhinosinusitis

Overview

This systematic review and meta-analysis compares the prevalence of bacterial pathogens in acute rhinosinusitis (ARS) and chronic rhinosinusitis (CRS), with implications for empiric antibiotic therapy and antimicrobial stewardship.

Background

Sinusitis, including acute and chronic forms, affects approximately 15% of the US population, or more than 35 million people annually. More than 90% of cases are viral, and approximately 0.5% to 2% of adult viral cases develop secondary acute bacterial rhinosinusitis.

Data Highlights

The analysis included 57 studies: 16 involving ARS and 41 involving CRS. These studies represented 1776 acute and 9056 chronic sinus specimens. Random-effects meta-analysis was used to estimate pooled pathogen prevalence.

Key Findings

• In ARS, methicillin-susceptible Staphylococcus aureus (MSSA) was the most prevalent isolate at 20.5%, followed by coagulase-negative staphylococci at 16.9% and Streptococcus pneumoniae at 16.3%.

• MSSA surpassed the respiratory pathogens traditionally associated with bacterial ARS, including S pneumoniae and Haemophilus influenzae.

• CRS had broader polymicrobial flora, with coagulase-negative staphylococci at 24.3% and MSSA at 22.5%.

• S pneumoniae was less prevalent in CRS at 9.4%, reflecting the distinct microbiological profile of chronic disease.

• Pooled prevalence estimates showed substantial between-study heterogeneity.

Clinical Implications

Antibiotics for ARS should be reserved for cases meeting clinical criteria for bacterial infection, with treatment using the narrowest effective spectrum for the shortest necessary duration. CRS management should prioritize anti-inflammatory therapy and improved sinus drainage, with antibiotics used sparingly during bacterial exacerbations. When antibiotics are required for CRS, individualized, culture-guided treatment may be appropriate because its bacterial flora are more diverse.

Conclusion

ARS and CRS have markedly different bacterial pathogen profiles. Recognizing these differences can support condition-specific empiric antibiotic strategies, more targeted clinical management, and improved antimicrobial stewardship.

Related Resources & Content

1. A systematic review and meta-analysis of bacterial pathogen prevalence in acute and chronic rhinosinusitis: implications for empiric antibiotic therapy and antimicrobial stewardship — International Journal of Infectious Diseases, 2026

2. PRISMA 2020 statement for reporting systematic reviews

3. European Position Paper on Rhinosinusitis and Nasal Polyps 2020

4. IDSA clinical practice guideline for acute bacterial rhinosinusitis in children and adults

5. Clinical practice guideline update on adult sinusitis

6. Review of the microbiology of chronic rhinosinusitis

7. Systematic review of the microbiology of acute CRS exacerbations

8. Study comparing empiric and culture-directed antibiotics for acute CRS exacerbations