Chronic Rhinosinusitis Organism-Specific Therapy

Updated: Feb 14, 2023
Author: Itzhak Brook, MD, MSc; Chief Editor: Thomas E Herchline, MD 

Specific Organisms and Therapeutic Regimens

The goal of antimicrobial therapy is to promote sinus drainage, reduce chronic inflammation, improve the quality of life, and eradicate infecting pathogens.[1] A comprehensive approach using topical or oral glucocorticoids, antibiotics, and nasal irrigation is beneficial in the treatment of chronic rhinosinusitis.[2, 3, 4, 5, 6, 7, 8, 9, 10, 11]

Organism-specific therapeutic regimens for chronic rhinosinusitis are outlined below, including those for Streptococcus pneumoniae, Haemophilus influenzae and/or Moraxella catarrhalis, Staphylococcus aureus, Pseudomonas aeruginosa, anaerobic and micoaerophilic gram positive cocci and gram-negative bacilli.[2, 3, 4, 5, 6, 7, 12]  Combined therapy may be needed to treat polymicrobial infection. Coverage for anaerobic bacteria is recommended when appropriate methodes  for their identefication are not used.{ref 7}

Streptococcus pneumoniae

Penicillin-susceptible:

  • Amoxicillin 500 mg to 1 g PO q8h

  • Duration of therapy: A trial of 14-28d is reasonable; longer durations (up to 6wk) may be required for refractory cases

Penicillin-resistant:

  • Moxifloxacin 400 mg PO/IV daily or

  • Levofloxacin 500 mg PO daily or

  • Vancomycin 1 g or 15 mg/kg IV q12h

  • Duration of therapy: A trial of 14-28d is reasonable; longer durations (up to 6wk) may be required for refractory cases

Haemophilus influenzae and/or Moraxella catarrhalis

Treatment of H inluenzae and/or Moraxella catarrhalis includes the following:

  • Amoxicillin-clavulanate 500 mg PO q8h or 875 mg PO q12h or

  • Moxifloxacin 400 mg PO/IV daily or

  • Levofloxacin 500 mg PO daily or

  • Cefuroxime 500 mg PO BID

  • Duration of therapy: A trial of 14-28 d is reasonable; longer durations (up to 6wk) may be required for refractory cases

Staphylococcus aureus

Methicillin-sensitive S aureus (MSSA):

  • Amoxicillin-clavulanate 500 mg PO q8h or 875 mg PO q12h or

  • Cefuroxime 500 mg PO BID or

  • Dicloxacillin 250 mg PO every 6 hr

  • Duration of therapy: A trial of 14-28d is reasonable; longer durations (up to 6wk) may be required for refractory cases

Methicillin-resistant S aureus (MRSA):

  • Clindamycin 300-450 mg PO q6-8h or

  • Trimetoprim-sulfamethoxazole TMP 80 mg and SMX 400 mg tab q12 or 24h or

  • Doxycycline 100 mg PO once daily or

  • Vancomycin 1 g or 15 mg/kg IV q12h or

  • Daptomycin 4 mg/kg IV once daily or

  • Linezolid 600 mg IV/PO BID

  • Duration of therapy: A trial of 14-28d is reasonable; longer durations (up to 6wk) may be required for refractory cases

Pseudomonas aeruginosa

Treatment for P aeruginosa includes the following:

  • Ciprofloxacin 500-750 mg PO q12h or 400mg q8-12h IV or

  • Levofloxacin 500-750 mg PO/IV daily or

  • Cefepime 2 g IM/IV q12h

  • Duration of therapy: A trial of 14-28d is reasonable; longer durations (up to 6wk) may be required for refractory cases

Anaerobic gram negative bacilli, and anaerobic or microaerophilic cocci

Treatment for anaerobic gram negative bacilli, and anaerobic or microaerophilic cocci includes the following:

  • Clindamycin 300-450 mg PO q6-8h or

  • Moxifloxacin 400 mg PO daily or

  • Amoxicillin-clavulanate 500 mg PO q8h or 875 mg PO q12h

  • Metronidazole  250-500 mg PO q8h (not effective against anaerobic and micaerophilic cocci)

  • Duration of therapy: A trial of 14-28d is reasonable; longer durations (up to 6wk) may be required for refractory cases