Rhinosinusitis is generally classified according to the duration into: (1,2)
- acute rhinosinusitis (ARS) - if duration of symptoms is less than 12 weeks
- chronic rhinosinusitis (CRS) - if lasting more than 12 weeks (with or without acute exacerbations)
Acute rhinosinusitis can be further divided into
- acute viral rhinosinusitis (common cold) - duration of symptoms of less than 10 days
- acute post-viral rhinosinusitis - defined by an increase in symptoms after 5 days or persistent symptoms after 10 days with less than 12 weeks duration.
- acute bacterial rhinosinusitis—defined by the presence of at least three symptoms or signs of
- discoloured discharge (with unilateral predominance) and purulent secretions
- severe local pain (with unilateral predominance)
- fever (>38°C)
- elevated erythrocyte sedimentation rate or C reactive protein
- ‘double sickening’ (i.e. a deterioration after an initial milder phase of illness)
- in recurrent acute sinusitis
- there are four or more episodes of acute bacterial rhinosinusitis per year without signs or symptoms of sinusitis between episodes
- each episode should meet the diagnostic criteria for acute bacterial sinusitis
Reference:
- Rosenfeld RM, Piccirillo JF, Chandrasekhar SS, et al. Clinical practice guideline (update): adult sinusitis. Otolaryngol Head Neck Surg. 2015 Apr;152(2 Suppl):S1-39.
- Peters AT, Spector S, Hsu J, et al. Diagnosis and management of rhinosinusitis: a practice parameter update. Ann Allergy Asthma Immunol. 2014 Oct;113(4):347-85.