What are the types of chronic rhinosinusitis and how is it treated in a patient with a history of recurrent sinus infections?

Chronic Rhinosinusitis Classification and Management

Chronic rhinosinusitis is classified into two primary types based on duration and presentation: chronic rhinosinusitis with nasal polyps (CRSwNP) and chronic rhinosinusitis without nasal polyps (CRSsNP), with CRS defined as persistent sinus inflammation lasting greater than 8-12 weeks. 1

Primary Classification System

Duration-Based Categories

• Acute rhinosinusitis (ARS): Symptoms lasting less than 4 weeks, consisting of purulent rhinorrhea, postnasal drainage, nasal congestion, facial pain, headache, fever, and cough 1
• Subacute rhinosinusitis: Symptoms persisting 4 to 8 weeks, representing unresolved acute sinusitis 1
• Chronic rhinosinusitis (CRS): Persistent sinus inflammation for greater than 8-12 weeks, documented with imaging techniques at least 4 weeks after appropriate medical therapy 1
• Recurrent acute rhinosinusitis: Three or more episodes of acute bacterial rhinosinusitis per year with symptom-free intervals between episodes 1, 2

Polyp-Based Subtypes

The presence or absence of nasal polyps fundamentally alters treatment approach and prognosis, making this the most clinically relevant classification. 1

• CRS without nasal polyps (CRSsNP): Approximately 96% of CRS cases, generally better prognosis 1
• CRS with nasal polyps (CRSwNP): Approximately 4% of CRS cases, associated with asthma, aspirin sensitivity, and higher recurrence rates 1, 3

Advanced Pathophysiologic Classification

Eosinophilic vs. Non-Eosinophilic Disease

Chronic hyperplastic eosinophilic sinusitis represents a distinct noninfectious subtype marked by eosinophil predominance, often associated with nasal polyps, asthma, and aspirin sensitivity. 1

• Chronic infectious sinusitis: Characterized by anaerobic bacteria (gram-positive streptococcus, bacteroides, Fusobacterium species, or S. aureus) with significant neutrophil influx 1
• Chronic hyperplastic eosinophilic sinusitis: Preponderance of eosinophils and mixed mononuclear cells with relative paucity of neutrophils, frequently refractory to standard treatment 1, 4

Emerging Endotype Classification

• Type 2 inflammation: Characterized by eosinophilic infiltration, Th2 cytokines, more severe symptoms, and higher surgical recurrence rates 3, 5
• Non-type 2 inflammation: Neutrophil-dominant patterns with different therapeutic responses 1, 5

Treatment Algorithm for Recurrent Sinus Infections

First-Line Medical Management (Mandatory Before Imaging)

All patients must complete 4-6 weeks of daily intranasal corticosteroids and high-volume saline irrigation before any CT imaging is obtained. 6, 2

• Daily high-volume saline nasal irrigation: Improves mucociliary function, decreases mucosal edema, mechanically removes infectious debris and allergens 6, 2
• Daily intranasal corticosteroids (fluticasone, mometasone, or budesonide): Reduces inflammation, improves sinus drainage, minimal systemic absorption 6, 2, 7
• Environmental remediation: Address mold and allergen exposure in home environment 6

Evaluation for Modifying Factors

Clinicians must assess for factors that fundamentally alter management: allergic rhinitis, cystic fibrosis, immunocompromised state, ciliary dyskinesia, and anatomical variation. 1

• Allergy evaluation: Allergic rhinitis frequently contributes to recurrent sinusitis; referral to allergist may be necessary 2
• Immunodeficiency screening: Quantitative immunoglobulin measurements (IgG, IgA, IgM), pre- and post-immunization antibody responses to tetanus toxoid and pneumococcal vaccines, particularly when aggressive management has failed 1
• Nasal endoscopy: Confirms presence or absence of polyps, purulent drainage, anatomical obstructions 1, 2

Imaging Indications

CT imaging is indicated only after symptoms persist ≥12 weeks for CRS or ≥4 documented episodes per year for recurrent acute rhinosinusitis, AND after failed trial of topical intranasal corticosteroids and saline irrigation for 4-6 weeks. 6

• Coronal CT scan: Gold standard for evaluating extent of disease, anatomical variants, sinonasal polyposis, and excluding neoplastic disease 1, 8
• Critical pitfall: CT findings do not correlate with symptom severity; up to 90% of viral upper respiratory infections show CT abnormalities that resolve without intervention 6

Acute Exacerbation Management

• High-dose amoxicillin-clavulanate: First-line antibiotic for confirmed acute bacterial episodes 2
• Broader-spectrum antibiotics: Consider if no improvement in 3-5 days 2
• Avoid azithromycin: Inadequate for chronic/recurrent sinusitis due to weak activity against resistant organisms 6

Surgical Referral Criteria

Refer to otolaryngology when anatomical abnormalities, nasal polyps, or persistent symptoms despite 4-6 weeks of aggressive medical management are present. 2

• Functional endoscopic sinus surgery (FESS): Improves sinus ventilation and drainage by widening natural drainage openings while preserving ciliated epithelium 2, 7
• Post-surgical management: Continue medical treatment with intranasal corticosteroids and saline irrigation indefinitely 1, 7
• Follow-up timing: Assess outcomes between 3-12 months post-surgery through history and nasal endoscopy 1

Critical Clinical Pitfalls

• Systemic steroids are not a substitute for topical intranasal corticosteroids—they have different roles and both must be attempted 6
• Never order CT imaging before completing mandatory 4-6 week trial of intranasal corticosteroids and saline irrigation—this represents inappropriate resource utilization 6
• IgG subclasses should not be checked routinely—the connection to recurrent CRS is controversial and clinical significance unclear 1
• Symptom-based diagnosis alone is insufficient—more than 50% of patients with strong history of chronic sinusitis have normal CT scans 1