الفهرس 
Anatomy of paranasal sinusesOnly 14 pages are availabe for public view
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Abstract
This guideline addresses sbacterial rhinosinusitis (ABRS), including (I) inability of existing clinicalcriteria to accurately differentiate bacterial from viral acute rhinosinusitis, leading to excessive and inappropriate antimicrobial therapy; (II) gaps in knowledge and quality evidence regarding empiric antimicrobial therapy for ABRS due to imprecise patient selection criteria; (III) changing prevalence and antimicrobial susceptibility profiles of bacterial isolates associated with ABRS; and (IV) impact of the use of conjugated vaccines for Streptococcus pneumoniae on the emergence of nonvaccine serotypes associated with ABRS (5). The justification for amoxicillin as first-line therapy for most patients with ABRS relates to its safety, efficacy, low cost, and narrow microbiologic spectrum (1, 6, 7). Consideration to prescribing amoxicillinclavulanate for adults with ABRS is given to those at a high risk of being infected by an organism resistant to amoxicillin (8). The Canadian guidelines base severity by the degree to which symptoms impair the patient. For symptoms that are mild to moderate in intensity, the guidelines recommend the use of intranasal corticosteroids (INCS)–but not antibiotics– as a first step in treatment. In mild tomoderate severity illness, antibiotics are reserved for patients who fail torespond to INCS after 3 days and whose symptoms continue for more than 7 days. For patients presenting with severe illness, INCS andantibiotics are recommended in combination as a first step in treatment.This approach thus reserves antibiotics for clear cases of ABRS that arenot resolving spontaneously.