Canadian clinical practice guidelines for acute and chronic rhinosinusitis

Advances in understanding the pathophysiology of CRS, along with the development of appropriate therapeutic strategies, have improved outcomes for patients with CRS. CRS now affects large numbers of patients globally and primary care practitioners are confronted by this disease on a daily basis. Although initially considered a chronic bacterial infection, CRS is now recognized as having multiple distinct components (eg, infection, inflammation), which have led to changes in therapeutic approaches (eg, increased use of corticosteroids). The role of bacteria in the persistence of chronic infections, and the roles of surgical and medical management are evolving. Although evidence is limited, guidance for managing patients with CRS would help practitioners less experienced in this area offer rational care. It is no longer reasonable to manage CRS as a prolonged version of ARS, but rather, specific therapeutic strategies adapted to pathogenesis must be developed and diffused.Guidelines must take into account all available evidence and incorporate these in an unbiased fashion into management recommendations based on the quality of evidence, therapeutic benefit, and risks incurred. This document is focused on readability rather than completeness, yet covers relevant information, offers summaries of areas where considerable evidence exists, and provides recommendations with an assessment of strength of the evidence base and degree of endorsement by the multidisciplinary expert group preparing the document.These guidelines have been copublished in both Allergy, Asthma & Clinical Immunology and the Journal of Otolaryngology-Head and Neck Surgery.Sinusitis refers to inflammation of a sinus, while rhinitis is inflammation of the nasal mucous membrane. The proximity between the sinus cavities and the nasal passages, as well as their common respiratory epithelium, lead to frequent simultaneous involvement of both structures (such as with viral infections). Given the difficulty se