Short-course therapy for acute sinusitis: how long is enough?

This review examines the issues surrounding short-course antibiotic therapy of acute sinusitis. Acute bacterial sinusitis is a common community-acquired infection defined as inflammation of one or more paranasal sinuses, most often the maxillary sinus. It is estimated that 0.5-5% of colds are complicated by acute sinusitis. Up to 1 in 20 upper respiratory tract infections is complicated by bacterial sinusitis, most often caused by Streptococcus pneumoniae, Haemophilus influenzae, Moraxella catarrhalis and Staphylococcus aureus. Early diagnosis and appropriate antibiotic therapy, in combination with agents that relieve nasal congestion, are important factors in preventing suppurative complications. Left untreated, it could lead to the development of chronic sinusitis or epidural or subdural empyema, brain abscess, or cavernosus sinus thrombosis. Isolation of the causal organism is often lacking in the community setting. Empiric antibiotic therapy should provide adequate coverage against the most important pathogens. Guidelines from different specialist societies based on current scientific knowledge are helpful in making the decision on which drug to use. Recommendations for duration of treatment of acute sinusitis are inconsistent between different guidelines but usually a 10- to 14-day treatment course is recommended.Recognition that the 10- to 14-day duration of therapy is not derived from a strong scientific or medical rationale has led some clinicians to call for shortening the duration of antibiotic therapy for patients with upper respiratory tract infections. Accumulating evidence suggests that short-course (< or =5 days) antibiotic therapy may have equivalent or superior efficacy compared with traditional longer (10-14 days) therapies and offers a number of advantages. Results of a number of clinical trials investigating 5-day therapy with oral cephalosporins, new quinolones or ketolides in acute (presumed) bacterial sinusitis in comparison with traditional 10-day treatment courses have been published demonstrating equivalent efficacy of 5-day and 10-day regimens. The evidence reviewed in this article strongly supports reduction of the traditional 10-day course of antibacterial therapy to a 5-day course for uncomplicated acute maxillary sinusitis in adults. Further research related to the duration of antibacterial therapy for sinusitis is needed in children and in adult patients with frontal, ethmoidal and sphenoidal sinusitis.