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Allergic Rhinitis & Asthma
Rhinitis
Characterised by 1 or more of the following:
Nasal congestion
Rhinorrhoea (anterior & posterior)
Sneezing
Itch
Allergic rhinitis – 50-70%
Non-allergic rhinitis
Infectious – viral (98%), bacterial
Drug-induced
ACE-inhibitor, NSAIDs
Rhinitis medicamentosa
Non-allergic rhinitis with eosinophilia syndrome (NARES)
Perennial symptoms, >20% eosinophils on nasal smears. Occasionally reduced sense of smell
Vasomotor (idiopathic)
Chronic nasal symptoms not immunologic or infectious in origin.
Occupational
Other
Food/alcohol, hormonal, atophic
Conditions that mimic rhinitis
Nasal polyps
Anatomical abnormalities
Cleft palate
Nasal septal deviation
Nasal tumours
Hypertrophy of adenoids/nasal turbinates
Trauma/foreign body
Laryngopharyngeal reflux
CSF rhinorrhoea
Ciliary dysfunction
Allergic Rhinitis
Affects 1 in 5 children in Australia/NZ
Prevalence of AR trebled over last 3 decades in UK serial
health surveys
Can lead to impaired concentration, impaired sleep,
reduced work/school performance
Typically requires a few years of allergen exposure to
develop
Risk Factors
Family history of atopy
Male
Birth during pollen season
Firstborn
Early use of antibiotics
Maternal smoking in first year of life
Exposure to indoor allergens eg. House dust mite
Pathophysiology of AR
Classification of AR
History
Nasal symptoms
Sneezing, itchy nose/palate
Rhinorrhoea, nasal obstruction
Colour: clear, purulent, blood
Unilateral or bilateral
Mouth-breathing, snoring, nasal voice, anosmia
Eye symptoms
Itch, hyperaemia, watering, periorbital oedema
Timing & frequency
Seasonal vs perennial, triggers
Severity
Troublesome symptoms
Sleep disturbance
Functional impact on school/work
Asthma
Examination
Pale, oedematous nasal turbinates
Excoriation of external nares
Transverse nasal crease
Allergic shiners (infraorbital oedema & darkening)
Dennie-Morgan lines (accentuated folds below lower eyelids
High arched palate, mouth breathing
Dental malocclusion
Investigations
Allergens tested dependent on basis of age, history & environment
Skin prick testing
Specific IgE (in vitro testing)
Perennial – HDM
Seasonal – grasses
Management
1. Allergen Avoidance
2. Pharmacotherapy
3. Immunotherapy
Allergen Avoidance
House dust mite avoidance
HDM allergen contained within its body parts & faecal particles
HDM feed on skin flakes contained within dust
Greatest exposure usually in sleep
Allergen-impermeable covers for mattresses, duvets & pillows
Remove sheepskin or woolen underlay
Remove reservoirs (toys, clothing, furnishings, drapes)
Weekly:
Wash all bed linen in hot water (> 60 °C)
Vacuum carpet
? Acaricide sprays
Allergen Avoidance
Pollen Avoidance
Avoid activities with high exposure to pollens
Avoid going outdoors before midday, on windy days or after thunderstorms
Avoid mowing the lawn
Wear sunglasses
Shower after arriving home
Home
Keep windows closed
Remove weeds or trees outside bedroom if sensitive
Keep pets outside
Oral Antihistamines
Antihistamines
Block H1 receptor
Effective against histamine-mediated symptoms
Second generation AH preferred
1st gen: sedation, anticholinergic effects
Paediatric suspensions
Cetirizine (zyrtec) > 12 mo
Loratadine (Claratyne) > 12 mo
Desloratadine (Aerius) > 12 mo; > 6mo for hives
Decongestants
Α-adrenenergic agonists = Pseudoephedrine &
phenylephrine
Can reduce nasal congestion
Side effects: insomnia, irritability, palpitations
Use with caution in young children
SHORT-TERM or intermittent/episodic therapy
NOT for regular daily use (> 4 days) due to risk of rhinitis
medicamentosa
Intranasal Steroids
Act by suppressing inflammation at multiple points in inflammatory cascade
Most efficacious drug available for both allergic & non-allergic rhinitis
Effective against both nasal congestion & ocular symptoms
Superior to antihistamines
Onset of action: 7-8 hours after dosing, but maximum efficacy takes up to 2 weeks
PRN use may not be as effective as continuous use
Local side effects typically minimal
Nasal irritation, bleeding
Rare: nasal septal perforation
Intranasal Steroids
Immunotherapy
First introduced in treatment of respiratory allergy since
1911
Gradual administration of increasing quantities of an
allergen extract to an allergic subject
Ameliorates the symptoms associated with subsequent
exposure to the causative allergen
Subcutaneous or sublingual administration
Immunotherapy
Indications:
History indicating exposure to particular allergen precipitates symptoms
Documented sensitivity to aeroallergen
Further exposure unavoidable or only partially avoidable
An effective allergen extract is available
Poor response to previous pharmacotherapy for allergic rhinitis
Contraindications
Unstable/severe asthma
Concomitant illness
Pregnancy
Beta-blocker treatment
Poor adherence
Mechanism of Immunotherapy
Immunotherapy
SCIT SLIT
Administration Subcutaneous
injections
Drops/tablets held for
2 minutes
Setting Doctor’s office Home
Maintenance 4-weekly doses 3x/week or weekly
doses
Cost $250-
300/allergen/year
$600-
750/allergen/year
Systemic AE 0.05 – 3.2% of doses 0.06% of doses
Fatalities 1 in 2-2.5 million None reported
Efficacy Beneficial for adults
with AR & asthma.
Inconclusive for
children (few trials)
Beneficial for AR in
adults & children.
When to refer?
Allergy Specialist
Significant symptoms despite compliance with regular
intranasal corticosteroids >3-6/12
Ensure correct technique
Asthma & AR
‘one airway, one disease’
AR & asthma frequently co-exist
75% patients with asthma have AR
In rhinitis patients, asthma prevalence 10-40%
Patients without rhinitis, asthma prevalence < 2%
AR increases risk of developing asthma by 2-3 times
Increases risk of asthma attacks, GP & emergency visits &
hospitalisations for asthma
Higher asthma drug costs & increased work absence
Treating AR can reduce asthma-related emergency
department visits & hospitalisations
Treatment of rhinitis & asthma
using a single approach
Oral H1-antihistamines are not recommended, but not
contraindicated in the treatment of asthma.
Intranasal steroids are at best moderately effective in
asthma.
may be effective in reducing asthma exacerbations and
hospitalizations.
The role of intrabronchial steroids in rhinitis unknown.
Montelukast is effective in the treatment of allergic rhinitis
and asthma in patients over 6 years of age.
Subcutaneous immunotherapy is recommended in both rhinitis
and asthma in adults
Summary
Rhinitis – allergic & non-allergic
Look up the nose!
Mild/intermittent: oral antihistamines
Moderate/severe/persistent: IN corticosteroids (use regularly)
If failed treatment, consider referral for possible immunotherapy
Asthma
Majority have rhinitis
Always ask about and optimise rhinitis treatment in patients with asthma
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