Sinusitis
[Clin Infect Dis 2012;Mar:e1-41, Pediatrics 2013;132:e284-96.]
- Most common predisposing factor is viral upper respiratory tract infection. Preschool and school age children can have 6-10 viral URTIs per year. Bacterial sinusitis complicates only <5% of these.
- The role of Mycoplasma pneumoniae and Chlamydia pneumoniae in acute sinusitis has been suggested but not substantiated. Empiric therapy for these organisms is not recommended.
Common presentation
- A bacterial etiology is more likely if: URTI symptoms persist for at least 10 days or worsen after 5-7 days with purulent nasal discharge +/- fever, cough, irritability, lethargy, facial pain.
Severe presentation (uncommon)
- Severely ill child with fever ≥ 39°C (unresponsive to appropriately dosed antipyretics) and purulent nasal discharge usually associated with facial swelling, sinus tenderness, headache.
Diagnosis
- The colour of nasal discharge/sputum should not be used to diagnose the sinusitis episode as bacterial since colour is related to presence of neutrophils, not bacteria.
- Nasopharyngeal cultures are not helpful in identifying etiological sinus pathogen(s).
- Sinus x-rays are not recommended as they will not differentiate between viral URTI and bacterial sinusitis.
- CT scan is only recommended for complications of acute sinusitis, chronic sinusitis not responding to treatment, and/or severe presentations where hospitalization is required.
- MRI not recommended due to poor bone definition.
Management
- Adjunctive therapy with nasal irrigation with saline solution or steam inhalation, and/or short term topical or systemic decongestant in children > 2 years only, may be helpful. Prolonged (> 5 days) use of topical decongestants should be avoided as it may lead to rebound symptoms.
NB: Antihistamines and mucolytics have no role in the management of acute sinusitis.
- The use of topical (intranasal) corticosteroids is controversial but may offer some benefit, especially in patients with allergic rhinosinusitis.
Antibiotic Therapy
- The benefit of antibiotic therapy in sinusitis is controversial (~70% resolve spontaneously).
- Some guidelines recommend high-dose amoxicillin-clavulanate instead of amoxicillin for first line treatment of sinusitis because of high rates of penicillin-resistant S. pneumoniae and β-lactamase producing H. influenzae and M. catarrhalis.
- High-dose amoxicillin remains a reasonable first-line empiric option given:
the lower resistance rates in Canada
amoxicillin retains best coverage of all oral β-lactam agents against S. pneumoniae (even majority of penicillin-resistant strains)
higher incidence of adverse effects of amoxicillin-clavulanate
need to limit broad spectrum antibiotic use in order to minimize the development of antibiotic resistance.
- Use of pneumococcal vaccines has shifted etiology of sinusitis such that H. influenzae and M. catarrhalis are more prevalent. Hence, if failure of therapy with amoxicillin, coverage of these organisms is recommended.
- Macrolides are no longer recommended for empiric therapy of sinusitis due to unpredictable/ poor activity against S. pneumoniae and H. influenzae.
- Levofloxacin has good coverage of the pathogens involved. However because of its broad spectrum, potential for increasing resistance, and risk of Clostridioides (Clostridium) difficile infection, it should be reserved for β-lactam allergic patients or patients who have failed first line antibiotic therapy.