How should acute, bacterial, and chronic sinusitis be treated?

Treatment of Sinusitis

For acute bacterial sinusitis, amoxicillin with or without clavulanate for 5-10 days is first-line therapy, but watchful waiting without antibiotics is equally appropriate for uncomplicated cases. 1, 2

Acute Bacterial Rhinosinusitis (ABRS)

Diagnosis First

Before treating, confirm ABRS by distinguishing it from viral upper respiratory infections. ABRS is diagnosed when: 1, 3

• Symptoms persist ≥10 days without improvement, OR
• Symptoms worsen within 10 days after initial improvement ("double worsening") 1
• Symptoms include purulent rhinorrhea, nasal congestion, facial pain, or postnasal drainage 1

Initial Management: Two Equally Valid Options

Option 1: Watchful Waiting (No Antibiotics) 1, 2

• Now recommended for ALL patients with uncomplicated ABRS, regardless of severity (expanded from prior guidelines that limited this to "mild" cases only) 2
• Reassess at 7 days if no improvement 1

Option 2: Antibiotic Therapy 1, 2

• First-line: Amoxicillin with or without clavulanate for 5-10 days 1, 2

• High-dose amoxicillin-clavulanate (90 mg/kg amoxicillin, 6.4 mg/kg clavulanate, max 2g q12h) for: 1

  • Patients who fail initial amoxicillin
  • Regions with high antibiotic resistance
  • Recent antibiotic use (within 6 weeks) 4

• Penicillin allergy alternatives: 1

  • Cephalosporins (cefuroxime, cefpodoxime, cefdinir)
  • Fluoroquinolones (for moderate disease with beta-lactam hypersensitivity) 4
  • Macrolides (clarithromycin, azithromycin) for serious drug allergy 5
  • Trimethoprim-sulfamethoxazole (adults only, check local resistance patterns) 1, 4

Reassessment at 3-7 Days

If symptoms worsen or fail to improve within 7 days: 1

• Confirm ABRS diagnosis
• Exclude complications (orbital swelling, severe headache, high fever) 1
• Switch antibiotics if already prescribed 1
• Consider broader-spectrum coverage: high-dose amoxicillin-clavulanate, cefuroxime, or fluoroquinolones 1

Adjunctive Therapies for ABRS

• Intranasal corticosteroids: Recommended, may provide modest benefit 1, 6
• Nasal saline irrigation: Recommended 6
• Analgesics: Based on pain severity 3
• Oral decongestants: May help, but topical decongestants should not exceed 3 days to avoid rebound congestion 4
• Avoid: Routine imaging unless complications suspected 1, 3

Chronic Rhinosinusitis (CRS)

Diagnosis Confirmation

CRS is defined as symptoms ≥8 weeks with objective documentation of sinonasal inflammation via: 1

• Anterior rhinoscopy, nasal endoscopy, OR
• CT or MRI showing abnormalities 1

Critical Distinction: Infectious vs. Non-Infectious CRS

CRS is primarily inflammatory, NOT infectious 1, 7

• Chronic hyperplastic eosinophilic sinusitis: eosinophil-predominant, does NOT respond to antibiotics 1
• Often associated with nasal polyps, asthma, aspirin sensitivity 1

When to Use Antibiotics in CRS

Do NOT prescribe antibiotics for CRS unless: 1

• Significant purulent nasal discharge (anterior, posterior, or both) is present on examination 1
• This is a strong recommendation to avoid indiscriminate antibiotic use 1

If purulent discharge present: 1

• Minimum 3 weeks of antibiotics effective against H. influenzae, mouth anaerobes, and S. pneumoniae 1
• Consider culture-directed therapy when possible 7

Macrolide antibiotics (long-term): 1, 7

• May benefit patients through anti-inflammatory/immunomodulatory effects 1
• Evidence is mixed; consider in patients with low IgE levels 7
• Duration: ≥3 weeks 1

Primary CRS Treatment (Non-Antibiotic)

Intranasal corticosteroids: 1

• Cornerstone of therapy 1
• Continue for minimum 3 months if symptoms resolve 1

Nasal saline irrigation: 1

• Recommended for all CRS patients 1

Oral corticosteroids: 1

• Consider for chronic hyperplastic eosinophilic sinusitis 1
• For patients with nasal polyps or marked mucosal edema 1
• Trial before considering surgery for obstructing polyps 1

Evaluate for Modifying Conditions

All CRS patients should be assessed for: 1, 2

• Allergic rhinitis (test for IgE sensitization) 1
• Asthma 1, 2
• Aspirin-exacerbated respiratory disease (AERD) 2
• Cystic fibrosis 1, 2
• Immunodeficiency 1, 2
• Ciliary dyskinesia 1, 2
• Anatomic abnormalities 1

When to Refer to Specialist

Allergist-immunologist: 1

• Recurrent or chronic sinusitis with otitis media, bronchitis, bronchiectasis, or pneumonia 1
• Prior surgical procedures with persistent symptoms 1
• Evaluation includes: quantitative IgG, IgA, IgM levels; specific antibody responses to tetanus/pneumococcal vaccines 1

Otolaryngologist: 1

• Structural abnormalities (septal deviation compressing middle turbinate, ostiomeatal obstruction) 1
• Obstructing nasal polyps after appropriate medical trial 1
• Failure to improve after 21-28 days of appropriate antibiotic treatment 1
• Consider CT scan before referral 1
• Functional endoscopic sinus surgery may be indicated 1

Recurrent Acute Rhinosinusitis

Defined as ≥3 episodes of acute sinusitis per year 1

Management approach: 1

• Evaluate for underlying inflammation, allergy, immunodeficiency, anatomic abnormalities 1
• Treat underlying allergic rhinitis: environmental control, pharmacotherapy, immunotherapy 1
• Consider specialist referral (allergist-immunologist or otolaryngologist) 1

Key Pitfalls to Avoid

• Do NOT use imaging routinely for uncomplicated acute sinusitis 1, 3
• Do NOT prescribe antibiotics empirically for CRS as a third-party requirement for surgery 2
• Do NOT use antibiotics for chronic hyperplastic eosinophilic sinusitis—use corticosteroids instead 1
• Do NOT ignore odontogenic sources in refractory sinusitis—requires dental surgery, not more antibiotics 7
• Do NOT use topical decongestants >3 days (causes rebound congestion) 4