What is the recommended initial treatment for acute bacterial rhinosinusitis?

Initial Treatment for Acute Bacterial Rhinosinusitis (ABRS)

For adults with uncomplicated ABRS, either watchful waiting (without antibiotics) or amoxicillin-clavulanate as first-line therapy for 5-7 days is recommended as the initial treatment approach. 1, 2

Diagnosis of ABRS

• ABRS should be diagnosed based on clinical criteria, including symptoms lasting >7 days, purulent nasal discharge, maxillary tooth/facial pain, unilateral sinus tenderness, and worsening symptoms after initial improvement 2
• Three clinical presentations suggest ABRS: persistent symptoms lasting ≥10 days without improvement, severe symptoms with high fever and purulent nasal discharge/facial pain, or a "double-sickening" pattern (worsening after initial improvement) 3
• Imaging is not recommended for uncomplicated ABRS due to high prevalence of abnormal findings in viral rhinosinusitis 2

Initial Management Algorithm

Step 1: Determine severity and risk factors

• Assess for risk factors for resistant pathogens: recent antibiotic use, comorbidities, immunocompromised state, severe symptoms 3
• Determine if symptoms are mild, moderate, or severe 1, 2

Step 2: Choose initial treatment approach

• For mild to moderate symptoms without risk factors:

  • Watchful waiting is appropriate if follow-up can be assured 1
  • Patient should seek care if condition worsens or fails to improve within 7 days 1

• For moderate to severe symptoms or presence of risk factors:

  • Initiate antibiotic therapy promptly 1, 2
  • First-line: Amoxicillin-clavulanate rather than amoxicillin alone 1, 2
  • Duration: 5-7 days for adults; 10-14 days for children 1, 2

• For penicillin-allergic patients:

  • Doxycycline or respiratory fluoroquinolones (e.g., levofloxacin) 2, 4
  • For mild disease with penicillin allergy: trimethoprim/sulfamethoxazole or doxycycline 5

Antibiotic Selection and Dosing

• First-line therapy: Amoxicillin-clavulanate 1, 2

  • Standard dose for mild disease with no risk factors for resistant pathogens 2
  • High-dose (2g orally twice daily or 90 mg/kg/day orally twice daily) for:
    • Areas with high prevalence of penicillin-resistant S. pneumoniae
    • Moderate to severe disease
    • Patients with risk factors for resistant pathogens 1, 2

• Alternative antibiotics for penicillin-allergic patients:

  • Doxycycline 5
  • Respiratory fluoroquinolones (e.g., levofloxacin) 4
  • Trimethoprim/sulfamethoxazole (for mild disease) 5

Adjunctive Treatments

• Recommended adjunctive treatments:

  • Intranasal saline irrigation with physiologic or hypertonic saline 1, 2
  • Intranasal corticosteroids, especially in patients with history of allergic rhinitis 1, 2
  • Acetaminophen or ibuprofen for pain and fever relief 1, 2

• Not recommended:

  • Topical or oral decongestants and/or antihistamines are not recommended as adjunctive treatment 1, 2
  • Routine coverage for Staphylococcus aureus (including MRSA) during initial empiric therapy 1, 2

Follow-up and Treatment Failure

• Reassess after 48-72 hours of initial empiric antimicrobial therapy if symptoms worsen 1
• Consider alternative management if symptoms fail to improve despite 3-5 days of initial empiric antimicrobial therapy 1, 2
• Options for treatment failure include:
  • Broadening antibiotic coverage
  • Extending treatment duration
  • Referral to specialist (otolaryngologist, infectious disease specialist) 2

Important Considerations and Pitfalls

• Most cases of acute rhinosinusitis are viral and resolve without antibiotics 1, 6
• Unnecessary antibiotic use contributes to antimicrobial resistance and exposes patients to potential adverse effects 1, 6
• The benefit of antibiotics is modest (10-15 patients must use antibiotics to get 1 more person better after 7-15 days) 1
• Short-course therapy (5-7 days) for adults appears as effective as traditional longer courses (10-14 days) with fewer side effects 7
• Prior antibiotic use within 4-6 weeks is a risk factor for infection with resistant organisms 2