Sinusitis Management

Classification

Common Pathogens

Acute Sinusitis

Step 1 - Distinguish Viral from Bacterial

Step 2 - Symptomatic Treatment (all patients)

• Intranasal decongestants: oxymetazoline 2 sprays each nostril BID - no more than 5 days
• Oral decongestants: pseudoephedrine 120 mg (12-h formulation) during the day
• Analgesics/antipyretics: acetaminophen or ibuprofen
• Nasal saline: sprays or higher-volume nasal washes - provide relief and improve drainage
• Intranasal glucocorticoids: especially helpful when there is an allergic component

Step 3 - Antibiotic Selection

• Amoxicillin-clavulanate 875/125 mg PO BID x 7 days (preferred)
• Amoxicillin 875 mg PO BID x 7 days (alternative, if no resistance risk)
• Course: complete 5-7 days if improving after 3-5 days

• Mild allergy: cefuroxime
• Severe allergy: doxycycline
• Macrolides are specifically NOT recommended due to high rates of macrolide-resistant S. pneumoniae

• Age <2 or >65 years, daycare attendance
• Prior antibiotics within the past month
• Prior hospitalization within 5 days
• Significant comorbidities
• Immunocompromised state

• Amoxicillin-clavulanate 2000/125 mg PO BID x 7 days
• Levofloxacin (fluoroquinolones - note risks: dysglycemia, neuropathy, tendon/aortic rupture)
• Complete 7-10 days if improving after 3-5 days

Red Flags - When to Seek Urgent Care

• Confusion, unilateral weakness
• Proptosis, limited ocular movements, acute vision changes
• Recurrent fever >102°F after initial improvement
• Rapidly worsening, persistent facial pain

Chronic Sinusitis (>12 weeks)

Three Main Types

1. Without polyps - more common in women; T-helper 1 predominance; bacterial etiology; facial pain prominent
2. With polyps - more common in men; T-helper 2 / eosinophilic inflammation; associated with asthma and aspirin sensitivity (Samter's triad); hyposmia/anosmia prominent
3. Allergic fungal rhinosinusitis - atopic patients in warm/humid regions; IgE-mediated + eosinophils; classically greenish-brown "peanut butter" mucus with viable fungal hyphae

Diagnosis

• Confirm with anterior rhinoscopy, nasal endoscopy, or imaging - up to 40% of patients with chronic sinus symptoms have no mucosal changes on exam
• Non-contrast CT is the imaging modality of choice - required before treatment to confirm diagnosis and identify polyps, septal deviation, allergic fungal sinusitis, or tumors

Medical Treatment

Surgical Treatment - Functional Endoscopic Sinus Surgery (FESS)

• Remove polyps from nasal cavity and paranasal sinuses
• Improve sinus drainage by restoring ostiomeatal unit patency
• Patients with more focal, limited disease have more reliable results
• For allergic fungal rhinosinusitis: surgery produces good results; medical therapy is classically ineffective; post-operative systemic glucocorticoids help prevent recurrence

Special Populations

Immunocompromised Patients (HIV, Transplant Recipients, Hematologic Malignancy)

• CD4 ≥200 cells/µL: treat with standard regimens
• CD4 <200 or ANC <600: broaden antibiotic coverage to include Staphylococcus, Pseudomonas, and anaerobes
• Invasive fungal sinusitis (IFS): treat with IV antifungals + urgent surgical debridement; evaluate with gadolinium-enhanced MRI; this is a medical/surgical emergency

Nosocomial Sinusitis

• Suspect in hospitalized patients with fever without identifiable cause, especially nasotracheal intubation
• Remove precipitating factors (remove nasal tube if possible)
• Empiric broad-spectrum antibiotics; tailor to culture and susceptibility results

Pediatric Sinusitis

• Diagnosis: persistent (>10 days) or severe URI symptoms, or double sickening
• Most common pathogens same as adults
• Imaging not recommended routinely - sinus mucosal changes present in 97% of infants within 2 weeks of URI
• Antibiotic of choice: amoxicillin-clavulanate (high-dose for resistant organisms)
• Efficacy of antibiotics for pediatric CRS has not been validated; evidence-based treatment differs from adults (a 2025 Italian intersociety consensus - PMID 40140854 - provides updated pediatric guidance)

Recurrent Acute Sinusitis (≥4 episodes/year)

• Nasal culture during episodes
• Imaging between episodes to identify predisposing anatomic abnormalities (deviated septum, polyps)
• Allergic and immunologic evaluation
• Consider ENT referral for FESS if structural abnormality identified

Summary Algorithm

Acute URI symptoms
      |
      v
Are criteria met? (Persistent ≥10d, Severe, or Worsening)
      |
   NO --> Symptomatic only (decongestants, analgesics, saline, intranasal steroid)
      |
  YES --> Risk factors for resistance?
              |
            NO --> Amoxicillin-clavulanate 875/125 mg BID x 7d
           YES --> Amoxicillin-clavulanate 2000/125 mg BID x 7d or levofloxacin
              |
          Reassess at 3-5 days
              |
         Improving --> Complete course
         Not improving --> Escalate / refer / CT scan

• Harrison's Principles of Internal Medicine 22E, pp. 298-300
• Textbook of Family Medicine 9e, pp. 421-426
• Tintinalli's Emergency Medicine, Ch. 123
• Cummings Otolaryngology Head and Neck Surgery
• IDSA Clinical Practice Guideline for ABRS (Chow et al., Clin Infect Dis 2012)
• Recent: Dupilumab vs. sinus surgery for CRS with polyps - systematic review/meta-analysis (Kim et al., Am J Rhinol Allergy 2024, PMID 39149992) - dupilumab shows comparable efficacy to surgery