Non-allergic Rhinitis

NAR Intro & Types - The Rhinitis Riddle

• Non-allergic Rhinitis (NAR): Chronic nasal symptoms (congestion, rhinorrhea, PND, sneeze) without IgE-mediated allergic inflammation.
• Diagnosis: Exclusion of allergic rhinitis (negative skin prick/serum specific IgE tests) & other sinonasal conditions.
• Key Types:
  • Vasomotor Rhinitis (Idiopathic): Most common; diagnosis of exclusion. Triggers: irritants, temperature/humidity changes.
  • NARES (Non-Allergic Rhinitis with Eosinophilia Syndrome).

    ⭐ Nasal eosinophilia >20% on cytology; negative allergy tests.

  • Gustatory Rhinitis: Prominent watery rhinorrhea with specific foods (e.g., hot, spicy).
  • Drug-induced Rhinitis:
    • Rhinitis Medicamentosa (topical decongestants >7-10 days).
    • Systemic: Aspirin/NSAIDs, ACE-I, β-blockers.
  • Hormonal Rhinitis: Pregnancy, hypothyroidism.
  • Atrophic Rhinitis (Ozena): Nasal crusting, fetor, atrophy.
  • Senile Rhinitis: Persistent watery rhinorrhea in elderly.

NAR Subtypes Deep Dive - Unmasking Mimics

• Vasomotor Rhinitis (Idiopathic):
  • Triggers: Temp/humidity shifts, irritants (smoke, scents), stress.
  • Pathophys: Autonomic dysregulation (↑parasympathetic).
  • Sx: Watery rhinorrhea, congestion.
• Gustatory Rhinitis:
  • Triggers: Hot/spicy foods.
  • Pathophys: Vagal reflex.
  • Sx: Profuse watery rhinorrhea with meals.
• Hormonal Rhinitis:
  • Triggers: Pregnancy (estrogen), OCPs, hypothyroidism.
  • Sx: Congestion, rhinorrhea.
• Drug-Induced (Rhinitis Medicamentosa - RM):
  • Triggers: Topical decongestants (>5-7 days), antihypertensives (ACEi, β-blockers), NSAIDs.
  • Pathophys: Rebound vasodilation.
  • Sx: Severe, constant congestion.
• NARES (Non-Allergic Rhinitis with Eosinophilia Syndrome):
  • Pathophys: Nasal eosinophilia (>20% on smear), non-IgE.
  • Sx: Perennial sneezing, rhinorrhea, itch, anosmia.

  ⭐ NARES often shows good response to intranasal corticosteroids.

• Atrophic Rhinitis (Ozena):
  • Pathophys: Mucosal/turbinate atrophy; K. ozaenae link.
  • Sx: Crusting, fetor (patient anosmic), paradoxical obstruction.
• Senile Rhinitis:
  • Pathophys: Age: ↓glandular activity, collagen alteration.
  • Sx: Persistent watery rhinorrhea ("senile drip").

Clinical Features & Diagnosis - Spotting Non-Allergic Sneezes

• Core Symptoms: Chronic/persistent nasal congestion, rhinorrhea (watery/mucoid), post-nasal drip, sneezing.
  • Often perennial; typically adult-onset.
  • Key differentiator: Minimal/absent itching (nasal, ocular), paroxysmal sneezing (vs. allergy). No systemic atopy signs.
• Common Triggers:
  • Irritants: Smoke, perfumes, pollutants, weather changes (temp, humidity).
  • Medications: Aspirin/NSAIDs, β-blockers, ACE inhibitors.
  • Hormonal: Pregnancy, hypothyroidism.
  • Gustatory: Spicy foods.
• Diagnostic Approach: Diagnosis of exclusion.

• Key Investigations:
  • Allergy tests (SPT/sIgE): Negative.
  • Nasal cytology: Eosinophils (>20% in NARES), neutrophils, or normal.
  • Nasal endoscopy: Rule out structural issues, polyps.

⭐ Non-Allergic Rhinitis (NAR) is diagnosed after allergic causes are excluded by negative skin prick tests or serum specific IgE tests for relevant aeroallergens.

NAR Management - Taming Troublesome Noses

• Conservative:
  • Identify & avoid specific triggers (e.g., smoke, strong odors, temperature shifts).
  • Nasal saline irrigation (isotonic or hypertonic) for symptomatic relief.
• Pharmacotherapy:

• Key Agents & Uses:
  • INS (e.g., fluticasone): 1st line, reduce inflammation, broad efficacy.
  • Intranasal Antihistamines (e.g., azelastine): Rapid onset, for congestion, sneezing, rhinorrhea.
  • Ipratropium Bromide (0.03%): Anticholinergic, for watery rhinorrhea (gustatory).
  • Capsaicin: Neuromodulation (TRPV1), for severe/refractory NAR.
• Surgical: For anatomical obstruction or refractory symptoms (turbinate reduction).

⭐ Intranasal corticosteroids (e.g., fluticasone, budesonide) are the cornerstone of NAR management due to their broad anti-inflammatory effects.

High‑Yield Points - ⚡ Biggest Takeaways

• Non-allergic Rhinitis (NAR): Chronic nasal symptoms without allergy or infection.
• Diagnosis of exclusion; negative allergy tests (skin prick/IgE) are key.
• Triggers: Irritants, weather, medications (NSAIDs, beta-blockers), hormonal changes.
• Subtypes: Vasomotor (commonest), NARES (nasal eosinophilia >20%), gustatory, drug-induced.
• Symptoms: Predominantly nasal congestion & watery rhinorrhea; less itching/sneezing than AR.
• Management: Intranasal corticosteroids (first-line), intranasal antihistamines.
• NARES responds well to intranasal steroids.