The role of antibiotics in treating chronic rhinosinusitis.

Chronic rhinosinusitis (CRS) is an inflammatory disease of the paranasal sinuses that occurs in 1% to 5% of the U.S. It may significantly decrease quality of life. CRS is defined as an inflammatory condition of the paranasal sinuses that persists for 12 weeks or longer, despite medical management. Treatment is directed at enhancing mucociliary clearance, improving sinus drainage/outflow, eradicating local infection (with antibiotics) and inflammation (with steroids), and improving access for topical medications.

The microbiology of rhinosinusitis evolves through several stages. The early phase (acute) is generally caused by a virus that may be followed by an aerobic bacterial infection in 2% to 10% of patients. Aerobic (Staphylococcus aureus) and anaerobic (Prevotella and Fusobacteria) members of the oral flora emerge as predominant sinus cavity isolates.

Antimicrobials are one component of comprehensive medical and surgical management for this disorder. Antimicrobialtherapy of chronic rhinosinusitis should be adequate against the potential aerobic and anaerobic pathogens. Because most of these infections are polymicrobial and many include beta-lactamase producing aerobic and anaerobic organisms, amoxicillin-clavulanate is the first-line regimen for most patients. Clindamycin is adequate for penicillin-allergic individuals and is also generally appropriate for methicillin resistant Staphylococcus aureus treatment is administered for at least three weeks and may be extended for up to 10 weeks in refractory cases. Treatment can be guided by a culture preferably from the sinus cavity obtained from individuals who have not shown improvement or deteriorated despite therapy.