What is the recommended treatment approach for a patient with chronic sinusitis, considering their medical history and potential allergies?

Treatment of Chronic Sinusitis

Begin with daily high-volume (150 ml) hypertonic (2%) saline irrigation combined with intranasal corticosteroid spray as first-line therapy for all patients with chronic sinusitis. 1, 2, 3

Initial Medical Management

First-Line Therapy (All Patients)

• Saline irrigation: Use large-volume (150 ml) hypertonic (2%) saline daily, which improves symptom scores significantly compared to no treatment (standardized mean difference 1.42) 3, 4
• Intranasal corticosteroids: Administer topical corticosteroid spray daily, which improves overall symptom scores (standardized mean difference -0.46) and is superior to placebo 1, 3
• Adjunctive measures: Recommend adequate hydration, analgesics for facial pain, warm facial compresses, and sleeping with head elevated 2

Distinguishing Infectious vs. Eosinophilic Chronic Sinusitis

This distinction is critical because treatment differs dramatically:

• Chronic infectious sinusitis (neutrophilic): Characterized by purulent discharge, neutrophils on biopsy, and responds to prolonged antibiotics 2
• Chronic eosinophilic sinusitis (hyperplastic): Characterized by eosinophils and mononuclear cells with few neutrophils, often associated with nasal polyps, asthma, and aspirin sensitivity, and does NOT respond to antibiotics 1, 2

Treatment Based on Sinusitis Type

For Chronic Infectious Sinusitis (Neutrophilic)

• Prolonged antibiotic therapy (21-28 days): Use high-dose amoxicillin-clavulanate, cefuroxime, or cefpodoxime as first-line agents 1, 2
• Add anaerobic coverage: Consider adding clindamycin or metronidazole if no improvement after initial therapy 1, 2
• Continue first-line therapy: Maintain saline irrigation and intranasal corticosteroids throughout antibiotic treatment 1, 2

For Chronic Eosinophilic Sinusitis (With or Without Polyps)

• Systemic corticosteroids: Prescribe oral prednisolone for 1-3 weeks, which reduces polyp size and improves symptoms for up to 3 months 1, 2, 3
• Leukotriene antagonists: Consider adding these agents, which improve nasal symptoms in patients with nasal polyps (P < 0.01) 3
• Doxycycline: A 3-week course reduces polyp size for up to 3 months after treatment (P < 0.001) 3
• Dupilumab (Dupixent): For patients aged 12 years and older with inadequately controlled chronic rhinosinusitis with nasal polyps, prescribe 300 mg subcutaneously every 2 weeks as add-on maintenance therapy 5

For Chronic Sinusitis Without Polyps

• Macrolide antibiotics: Consider a 3-month course (not 3 weeks), which improves quality of life at 24 weeks after therapy (standardized mean difference -0.43) 1, 3
• This is distinct from the short-course doxycycline used for polyps 3

Evaluation for Underlying Conditions

All patients with chronic or recurrent sinusitis require systematic evaluation for underlying causes: 1, 2

Allergic Rhinitis Assessment

• Test for IgE sensitization: Perform skin or blood testing for inhalant allergens in all patients with chronic sinusitis 1, 2
• Treat allergic rhinitis aggressively: Use environmental control measures, pharmacotherapy (intranasal corticosteroids, oral second-generation antihistamines), and consider allergen immunotherapy 1, 2

Anatomic Abnormalities

• Obtain CT imaging: Order coronal sinus CT with extra cuts through the ostiomeatal complex if symptoms persist despite 4 weeks of appropriate medical therapy 1, 2, 6
• Look for specific abnormalities: Significant nasal septal deviation compressing the middle turbinate, middle turbinate deformity, accessory structures blocking sinus drainage, or obstructing nasal polyps 1, 2

Immunodeficiency Screening

• Refer for immunologic evaluation: Patients with chronic sinusitis plus recurrent otitis media, bronchitis, bronchiectasis, or pneumonia require assessment 1, 2
• Laboratory testing: Measure quantitative serum IgG, IgA, and IgM levels and assess specific antibody responses to tetanus toxoid or pneumococcal polysaccharide vaccine 1

When Medical Therapy Fails

Indications for Specialist Referral

Refer to allergist-immunologist for: 1, 2

• Treatment of underlying allergic factors
• Evaluation for unusual pathogens and immunodeficiency
• Patients with chronic symptoms despite aggressive medical management

Refer to otolaryngologist for: 1, 2

• Structural abnormalities (septal deviation, turbinate deformity)
• Obstructing nasal polyps unresponsive to oral corticosteroids
• Radiographic evidence of ostiomeatal obstruction despite aggressive medical management

Surgical Intervention

• Maximize medical therapy first: Every effort should be made to optimize medical treatment, including allergy management, before proceeding with surgery 1, 2
• Functional endoscopic sinus surgery: Contemporary surgical therapy involves widening natural drainage openings while preserving ciliated epithelium 2
• Continue medical therapy postoperatively: Most patients benefit from continued individualized medical therapy, including intranasal corticosteroids and allergy management, after surgery 1, 2

Common Pitfalls to Avoid

• Do not use low-volume (5 ml) nebulized saline: This is inferior to intranasal corticosteroids and provides no benefit 4
• Do not prescribe antibiotics for eosinophilic sinusitis: These patients have a preponderance of eosinophils and mononuclear cells and will not respond to antibiotics 1, 2
• Do not use short-course macrolides: For chronic sinusitis without polyps, macrolides require 3 months of therapy, not 3 weeks 3
• Do not skip allergy evaluation: IgE sensitization testing is essential for all patients with chronic or recurrent sinusitis 1, 2, 6
• Do not order CT imaging initially: Reserve CT for patients who fail 4 weeks of appropriate medical therapy or when surgical intervention is being considered 2, 6