EENT · PANCE / PANRE

Chronic Rhinosinusitis (CRS)

Sinonasal inflammation ≥12 weeks, subclassified by polyp status; managed with topical therapy and surgery.

Also known as: chronic sinusitis, CRS, chronic rhinosinusitis with polyps, CRSwNP, CRSsNP

Overview

Symptomatic inflammation of the nose and paranasal sinuses for ≥12 consecutive weeks, with objective evidence of inflammation on nasal endoscopy or CT imaging. Subclassified as CRS with nasal polyps (CRSwNP) or without (CRSsNP).

Epidemiology

Affects 5-12% of US adults. CRSwNP accounts for ~20-30% of cases and is associated with asthma (especially aspirin-exacerbated respiratory disease — Samter triad). Female-to-male ratio for CRSsNP slightly female-predominant; CRSwNP male-predominant.

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Risk factors

Allergic rhinitis, asthma
Aspirin/NSAID sensitivity (Samter triad: nasal polyps + asthma + aspirin sensitivity)
Cystic fibrosis, primary ciliary dyskinesia
Immunodeficiency (CVID, IgA deficiency, HIV)
Gastroesophageal reflux
Smoking, air pollutants
Anatomic obstruction (deviated septum, concha bullosa, polyps)
Dental disease (odontogenic CRS)

Pathophysiology

Persistent mucosal inflammation impairs mucociliary clearance and sinus drainage. CRSsNP shows neutrophilic Th1/Th17 infiltrate. CRSwNP demonstrates eosinophilic Th2-driven inflammation with elevated IL-4/IL-5/IL-13 — the target of newer biologics. Bacterial biofilms and fungal colonization may perpetuate disease.

Clinical presentation

Symptoms

≥2 of the following for ≥12 weeks: mucopurulent drainage, nasal obstruction, facial pain/pressure/fullness, decreased smell (anosmia/hyposmia is hallmark of CRSwNP)
Postnasal drip with chronic throat clearing or cough
Headache, ear fullness, dental discomfort
Fatigue, halitosis, reduced quality of life

Signs / physical exam

Nasal endoscopy: mucopurulent discharge from middle meatus, edema/erythema, or polyps (pale gray grape-like)
Polyps visible on anterior rhinoscopy in CRSwNP
Hyposmia on bedside smell testing
Cobblestoned posterior pharynx from postnasal drip
Possible facial tenderness on palpation

Classic findings

CRSwNP: anosmia + bilateral pale polyps + asthma history (consider Samter if ASA-sensitive). CRSsNP: facial pressure + mucopurulent discharge without polyps.

Differential diagnosis

Recurrent acute rhinosinusitis — ≥4 discrete episodes/year with full resolution between, total <12 weeks symptomatic; treat each episode and evaluate predisposing factors
Allergic rhinitis — No CT mucosal disease; itching, sneezing, atopic history; intranasal steroid
Nonallergic rhinitis — Trigger-related symptoms without IgE sensitization or sinus inflammation
Allergic fungal rhinosinusitis — CRSwNP with thick allergic mucin containing fungal hyphae, hyperdense CT material, often unilateral expansion; surgery + topical steroids ± systemic
Granulomatosis with polyangiitis (GPA) — Saddle-nose deformity, ulcers, crusts, lung involvement; positive c-ANCA/PR3
Sarcoidosis — Strawberry-like nasal mucosa, multisystem involvement, elevated ACE, noncaseating granulomas
Sinonasal malignancy — Unilateral persistent symptoms, epistaxis, facial numbness, mass on endoscopy; imaging and biopsy
Cystic fibrosis — Childhood-onset CRS, nasal polyps in pediatric patient → sweat chloride test
Primary ciliary dyskinesia — CRS + bronchiectasis + situs inversus (Kartagener); nasal nitric oxide low, biopsy of cilia

Diagnostic workup

Diagnostic criteria

AAO-HNS 2015: symptoms ≥12 consecutive weeks consistent with CRS (≥2 of mucopurulent discharge, obstruction, facial pain/pressure, decreased smell) PLUS documented inflammation on endoscopy (purulent mucus or polyps in middle meatus, mucosal edema) OR CT (paranasal sinus mucosal thickening or opacification).

Labs

Allergy testing (skin prick or specific IgE) if concurrent allergic rhinitis suspected
Sweat chloride and/or CF genetic testing in pediatric CRSwNP or chronic refractory CRS
Immunoglobulin levels (IgG/IgA/IgM) and vaccine response titers in recurrent infections
Total IgE, peripheral eosinophil count — biomarkers for biologic candidacy in CRSwNP
ANCA, ACE if vasculitis or sarcoidosis suspected

Imaging

CT sinus without contrast — defines mucosal disease extent, anatomic variants, surgical planning. Lund-Mackay score quantifies severity
MRI if intracranial extension or sinonasal mass suspected
Nasal endoscopy (clinic) — direct visualization confirms inflammation; biopsy for masses or unilateral disease

Diagnostic algorithm

Feature	CRSsNP	CRSwNP
Polyps on endoscopy	Absent	Present (bilateral typical)
Anosmia	Less common	Hallmark feature
Asthma association	Sometimes	Strong (esp. AERD/Samter)
Inflammation type	Neutrophilic (Th1/Th17)	Eosinophilic (Th2)
Response to topical steroid	Moderate	Often robust
Biologics	Not indicated	Dupilumab, omalizumab, mepolizumab for refractory
Surgery role	Adjunct when medical fails	Common; high recurrence without ongoing topical therapy

Phenotypic differences between CRS without and with nasal polyps.

Treatment

First-line

Saline nasal irrigation — high-volume, low-pressure with neti pot or squeeze bottle daily
Intranasal corticosteroid — fluticasone, mometasone, budesonide — daily long-term; consider budesonide nasal rinse for refractory CRSwNP
Treat comorbidities: allergic rhinitis (oral or intranasal antihistamine), asthma (controller), GERD
Short course of oral corticosteroids (prednisone 0.5-1 mg/kg × 5-10 days) for severe symptoms or polyp shrinkage
Targeted antibiotics — amoxicillin-clavulanate or doxycycline × 3 weeks — only during acute bacterial exacerbations

Second-line / adjunct

Functional endoscopic sinus surgery (FESS) — for failure of medical therapy, recurrent acute exacerbations, polyps, or complications
Aspirin desensitization for Samter triad — improves polyp control and reduces revision surgery
Biologics for severe CRSwNP refractory to surgery and topical therapy — dupilumab (anti-IL-4Rα), omalizumab (anti-IgE), mepolizumab (anti-IL-5)
Long-term low-dose macrolide (azithromycin) — immunomodulatory; limited evidence in CRSsNP
Allergy immunotherapy if allergic component is dominant

Complications

Persistent QoL impairment, work/school disability
Acute bacterial exacerbations
Orbital and intracranial extension (mucocele, abscess) — less common than in acute disease but possible
Mucocele formation (especially frontal sinus)
Anosmia, dysosmia
Worsening asthma control
Sinonasal squamous cell carcinoma or inverted papilloma should be considered with unilateral persistent disease

PANCE pearls

Unilateral chronic sinusitis is a red flag — image and biopsy to exclude tumor, fungal disease, or odontogenic source.
CRSwNP with asthma + aspirin sensitivity = Samter triad (aspirin-exacerbated respiratory disease, AERD).
Anosmia points strongly toward polyposis — examine the nose carefully.
Avoid prolonged systemic antibiotics — topical therapy and surgery are more durable.
Pediatric polyposis demands CF workup — sweat chloride test.

References

AAO-HNS 2015 — Rosenfeld RM et al. Clinical Practice Guideline (Update): Adult Sinusitis. Otolaryngol Head Neck Surg 2015;152(2S):S1-S39
ICAR-RS 2021 — Orlandi RR et al. International Consensus Statement on Allergy and Rhinology: Rhinosinusitis 2021. Int Forum Allergy Rhinol 2021;11(3):213-739
EPOS 2020 — Fokkens WJ et al. European Position Paper on Rhinosinusitis and Nasal Polyps 2020. Rhinology 2020;58(S29):1-464

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