What is causing my chronic rhinosinusitis symptoms?

What Else Could Be Causing Your Chronic Rhinosinusitis?

Beyond infection, your chronic rhinosinusitis symptoms may be driven by allergic rhinitis, anatomic obstruction, fungal disease, gastroesophageal reflux, immunodeficiency, medication overuse, occupational exposures, or systemic inflammatory conditions—each requiring specific evaluation and targeted treatment. 1

Primary Non-Infectious Contributors

Allergic Rhinitis

• Allergic rhinitis is one of the most common underlying factors in chronic rhinosinusitis, found in a substantial proportion of patients with persistent sinus inflammation 1
• The inflammatory cascade from allergy creates mucosal swelling that obstructs sinus drainage, perpetuating the cycle of inflammation even without active bacterial infection 1
• Look for associated symptoms: sneezing, watery rhinorrhea, nasal itching, and itchy watery eyes that distinguish allergic from non-allergic causes 1
• Testing for specific allergen sensitivities through skin testing or serum IgE can guide targeted avoidance and immunotherapy strategies 1

Non-Allergic Rhinitis (NAR)

• Eosinophilic non-allergic rhinitis was identified in 26% of chronic rhinosinusitis patients in clinical studies 1
• This represents inflammation without identifiable allergen triggers, often requiring corticosteroid-based management rather than antihistamines 1
• Nasal cytology can differentiate between eosinophilic NAR, neutrophilic rhinitis, and vasomotor rhinitis patterns 1

Anatomic and Structural Causes

Anatomic Obstruction

• Deviated nasal septum, enlarged turbinates, or dysfunctional nasal valve can create mechanical obstruction that prevents normal sinus drainage 1
• Nasal polyps secondary to chronic inflammation become both consequence and perpetuating cause of rhinosinusitis 1
• Endoscopic examination is essential to identify these structural barriers that may require surgical correction 1
• Rare structural causes include neoplasms (neurofibroma, squamous cell carcinoma, inverting papilloma) that must be excluded in refractory cases 1

Fungal Etiologies

Allergic Fungal Sinusitis

• Consider this diagnosis in atopic patients with chronic sinusitis refractory to antibiotic treatment 1
• Key features include thick allergic fungal mucin containing eosinophils and fungal elements, nasal crusting, and polyposis 1
• Total IgE levels are commonly elevated, and skin testing is typically positive for dematiaceous fungi 1
• The inflammatory response to fungal antigens (not invasion) can cause bony destruction and orbital complications 1

Systemic and Environmental Factors

Gastroesophageal Reflux Disease (GERD)

• GERD has emerged as a contributing cause of chronic rhinosinusitis, with studies showing that medical treatment of reflux results in significant improvement of sinus symptoms 1
• This mechanism involves direct irritation of upper airway mucosa and potential aspiration of gastric contents 1

Medication-Induced Rhinitis (Rhinitis Medicamentosa)

• Long-term use of topical α-agonist decongestants (oxymetazoline) paradoxically causes rebound nasal congestion 1
• The nasal mucosa becomes refractory with continued use, requiring escalating doses and creating a cycle of dependency 1
• Obtaining careful medication history, including over-the-counter nasal sprays and cocaine use, is critical 1
• β-blockers can also cause nasal congestion as a systemic side effect 1

Occupational and Environmental Exposures

• Chronic exposure to physical or chemical irritants in the workplace can cause or aggravate rhinosinusitis 1
• Fragrances, cleaning agents, odors, smokes, fumes, and corrosive agents are common culprits 1
• Diagnosis requires correlation between symptom worsening and workplace exposure; industrial hygienist evaluation may be necessary 1

Immunologic and Systemic Disease

Immunodeficiency

• Humoral immunodeficiency is not uncommon in patients with refractory chronic rhinosinusitis 2
• Consider testing quantitative immunoglobulins, functional antibody responses, and HIV status in recurrent cases 1
• Rhinosinusitis is among the most common infectious complications of immunodeficiency 2

Cystic Fibrosis

• Quantitative sweat chloride testing and genetic testing should be considered in children with nasal polyps, Pseudomonas colonization, or early-onset chronic sinusitis 1
• These patients have abnormal mucociliary clearance that predisposes to chronic infection 1

Granulomatous and Vasculitic Diseases

• Wegener's granulomatosis (granulomatosis with polyangiitis) and Churg-Strauss vasculitis can present with chronic rhinosinusitis 1, 2
• These systemic conditions require specific immunosuppressive therapy beyond standard rhinosinusitis management 1, 2
• Consider in patients with constitutional symptoms, multisystem involvement, or treatment-refractory disease 2

Aspirin-Exacerbated Respiratory Disease

• Patients with aspirin sensitivity have more severe chronic rhinosinusitis with extensive polyposis 2
• This triad (asthma, nasal polyps, aspirin sensitivity) requires specific management including aspirin desensitization in selected cases 2

Ciliary Dysfunction

• Primary ciliary dyskinesia or acquired ciliary impairment prevents normal mucociliary clearance 1, 3
• Tracheal biopsy for evaluating ciliary structure and function should be considered in appropriate clinical contexts 1

Critical Diagnostic Approach

When symptoms persist despite appropriate medical therapy, systematic evaluation for these underlying causes is mandatory before concluding treatment failure 1:

• Obtain detailed medication history including over-the-counter products 1
• Assess for allergic symptoms and consider allergy testing 1
• Perform nasal endoscopy to identify anatomic abnormalities and polyps 1
• Order CT imaging to document extent of disease and anatomic variants 1
• Consider nasal cytology to differentiate inflammatory patterns 1
• Evaluate for GERD symptoms and consider empiric treatment trial 1
• Screen for immunodeficiency in recurrent cases 1, 2
• Assess occupational and environmental exposures 1

The key pitfall is treating chronic rhinosinusitis as purely infectious when the underlying driver is non-infectious inflammation, anatomic obstruction, or systemic disease 1, 4. Each of these etiologies requires specific targeted therapy rather than repeated courses of antibiotics 4, 5.