GP - Allergic rhinitis Flashcards
Compare and contrast common cold and allergic rhinitis
- Acute onset of symptoms within minutes following allergen exposure in allergic rhinitis, but symptoms develop gradually in a common cold
- No fever in allergic rhinitis, but fever can be present in a common cold
- Itchy eyes in allergic rhinitis, but rare in a common cold
- Myalgia, arthralgia are uncommon in allergic rhinitis, but are common in common cold
- Thin, watery, clear mucus in allergic rhinitis, but thick, green mucus in a common cold
- Common cold usually takes 1 week to resolve, while allergic rhinitis usually goes away as soon as the patient is no longer exposed to the allergen
What immunoglobulin is responsible for allergic rhinitis?
IgE
What are the causes of allergic rhinitis?
- Genetics
- Environmental
- House dust mites
- Animal dander
- Pollen
- Occupational - e.g. working with latex gloves, flour, wood dust, lab animals
Give 3 complications of allergic rhinitis
Impaired school and work performance
Sleep disturbance
Asthma (often co-exist with allergic rhinitis)
Sinusitis and nasal polyps
What symptoms would a patient with allergic rhinitis present with?
Symptoms:
- Nasal congestion, nasal discharge, sneezing, itchy palate, itchy nose, itchy red eyes with increased tear secretion, cough, post-nasal drip - usually develop within minutes following allergen exposure (pollens, dust mites, animal dander, occupational)
- Mouth breathing
- Personal or FHx of atopy - allergic rhinitis (hayfever), asthma, eczema
What signs would a a patient with allergic rhinitis present with?
Nasal intonation of voice
Allergic shiners - darkened eye shadows under lower eyelid due to chronic congestion
Horizontal nasal crease across the dorsum of nose (severe rhinitis)
Nasal mucosal swelling + greyish discoloration
Hypertrophic nasal turbinates
Give 3 differential diagnoses of allergic rhinitis
Infective rhinitis - cough, fever, lymphadenopathy, purulent nasal discharge
(If nasal discharge is clear, unlikely to be infective)
Autonomic/ irritant rhinitis - symptoms follow a known physical exposure (e.g. changes in temperature or humidity, or with exercise), or chemical irritant exposure (e.g. perfumes, tobacco smoke, odours)
What investigations can you request in GP for a patient with allergic rhinitis?
Skin prick test
OR
Measuring the level of serum IgE to allergens e.g. house dust mites, polle, animal dander
What advice would you give to a patient with allergic rhinitis as a GP?
- Advice on allergen avoidance
- For grass pollen allergy:
- Avoid walking in open grassy areas, particularly during early morning and early evening
- Keep windows shut in cars and buildings
- For dust mite allergy:
- Wash bedding and furry toys at least once a week at high temperatures
- Fit blinds that can be wiped clean instead of curtains
- Avoid use of carpets
- For animal allergy:
- Don’t allow animal in the house, if not possible, restrict their presence to bedrooms and kitchen
- Wash the animal and any surfaces they are in contact with regularly
- For occupational allergy:
- Use latex-free gloves, wear protective clothing, or a dust mask
- Ensure that their workplace is well-ventilated
- For grass pollen allergy:
- Advice on the use of nasal irrigation with saline
What medications can you give to the patient with allergic rhinitis?
For mild-moderate symptom:
- 1st line - intranasal antihistamine / oral antihistamine e.g. cetirizine (PRN)
For moderate-severe symptoms, or if initial drug treatment is ineffective:
- Intranasal corticosteroids - to be used during periods of allergen exposure
Advise the person to be reviewed in 2-4 weeks if symptoms persist after initial treatment
When would you refer patients with allergic rhinitis to ENT?
- Red flag features e.g. unilateral symptoms, blood-stained nasal discharge, recurrent nose bleed
- There is a nasal obstruction and structural abnormality e.g. deviated nasal septum which makes intranasal drug use difficult
- Persistent symptoms despite optimal management –> referral to allergic specialist
- Diagnosis is uncertain