Allergic Rhinitis Pathophysiology PDF

Allergic Rhinitis Pathophysiology Sensitization phase: Allergen exposure stimulates IgE mediated immune response Early Phase (within minutes of exposure): Release of mast cell mediators and additional mediators Rhinorrhea, sneezing, pruritus Cellular recruitment: Circulating leukocytes, especially e...

Allergic Rhinitis Pathophysiology Sensitization phase: Allergen exposure stimulates IgE mediated immune response Early Phase (within minutes of exposure): Release of mast cell mediators and additional mediators Rhinorrhea, sneezing, pruritus Cellular recruitment: Circulating leukocytes, especially eosinophils, are attracted to nasal mucosa and release more inflammatory mediators Late Phase (2-4 hours after exposure): Nasal congestion, postnasal drainage, mucous hypersecretion due to submucosal gland hypertrophy and congestion Lowers the threshold for allergic- and nonallergic-mediated triggers Allergic vs Nonallergic Rhinitis ALLERGIC RHINITIS: Bilateral symptoms Worse in morning and at night Sneezing Runny nose (watery) Conjunctivitis Sinus pain Throat pain (postnasal drip) Allergic shiner, gape, salute, crease, or Dennie’s line NONALLERGIC RHINITIS: Unilateral (may be bilateral) Symptoms through the day Postnasal drip (water or thick) Severe nasal obstruction Anosmia Epistaxis Nasal polyps, septal deviation, enlarged tonsils Allergen Identification Outdoor, indoor, and occupational allergens Pollen, mold spores, dust mites, pet dander, etc. Outdoor aeroallergens: pollen, mold spores Environmental triggers: pollutants such as, tobacco smoke, ozone, diesel exhaust Indoor aeroallergens: house-dust mites, cockroaches, mold spores, pet dander Occupational aeroallergens: wool dust, latex, resins, organic dusts, chemicals Risk Factors Family history, socioeconomic status, eczema Positive skin allergy test reaction Possible link to childhood diet Exclusions to Self-Care Children less than 12 years Pregnant or lactating women* Symptoms of nonallergic rhinitis Symptoms of otitis media, sinusitis, bronchitis, or other infection Symptoms of undiagnosed or uncontrolled asthma (e.g. wheezing, shortness of breath) COPD or other lower respiratory disorder Symptoms unresponsive to treatment Severe or unacceptable side effects of treatment *unless already diagnosed and OTC therapy approved by PCP Classification of Allergic Rhinitis Intermittent: Symptoms occur less than 4 days per week OR less than 4 weeks Severity: Mild: Symptoms do not impair sleep or daily activities; No troublesome symptoms Persistent: Symptoms occur more than 4 days per week AND more than 4 weeks Symptoms: symptoms do not impair sleep or daily activities Classification of Allergic Rhinitis: Episodic: symptoms occur if an individual is in contact with an exposure than is not normally part of the individuals' environment (ex: cat at a friends house) Symptoms typically present after age 2 After age 65 allergic rhinitis cases decrease Allergen Avoidance Seasonal Allergies: Avoid outdoor activities when pollen counts are high Close windows and doors Avoid outdoor activities that increase exposure to mold spores Use air-conditioning and HEPA filters Perennial Allergies: Avoid dust mites Remove carpeting Reduce humidity to less that 40% Wash bedding in hot water at least once a week Avoid having pets in the house Avoid triggers (smoke, perfumes, pollution, etc.) Nonpharmacologic Therapies Nasal irrigation Isotonic or hypertonic saline Neti pots, bulb syringes, sprays Help relieve nasal irritation, dryness and remove dry, encrusted or thick mucous Modest benefits with rhinorrhea Pharmacologic Therapies Intranasal corticosteroids, antihistamines, decongestants, mast cell stabilizers Symptom effectiveness of different drug classes Intranasal Corticosteroids Triamcinolone 55mcg (Nasacort) Fluticasone furoate 27.5mcg (Flonase Sensimist) Fluticasone propionate 50mcg (Flonase) Budesonide 32mcg (Rhinocort) MOA: Anti-inflammatory that decreases mediators of inflammation Onset in 30 minutes with maximal benefits not seen for up to 1 to 2 weeks, Best if used on a continuous basis For seasonal allergies, start 2 weeks before allergy season Adverse Effects: Epistaxis, headache, bitter taste, pharyngitis, nasal dryness, sneezing, cough Minimal systemic adverse effects Potential for slower growth rate in children when used for more than 2 months/year Inappropriate nasal spray technique can cause septal perforation Drug Interactions: CYP 3A4 inhibitors Systemic Azole Antifungals Protease Inhibitors (HIV) Triamcinolone Dosing Adults and children more than or 12 years: 2 sprays in each nostril once daily o Reduce to 1 spray in each nostril daily once symptoms improve Children 6 - less than 12 years: 1 spray in each nostril once daily o May increase to 2 sprays if symptoms do not improve o Reduce to 1 spray in each nostril daily once symptoms improve Children 2- 5 years: 1 spray once daily in each nostril Children less than 2 years: Do not use Fluticasone Dosing Adults and children more or 12 years: 2 sprays in each nostril once daily o Reduce to 1 spray in each nostril daily once symptoms improve Children 4 - 11 years: 1 spray in each nostril once daily Children less than 4 years: Do not use Do not use; Flonase Sensimist can be used unless