WHAT IS ALLERGIC RHINITIS
Allergic rhinitis is defined clinically by the symptoms caused by immunologically mediated (most often IgE-dependent) inflammation after the exposure of the nasal mucous membranes to offending allergens.
The problem with allergies such as Hay fever and Allergic Rhinitis is that it is considered to be a trivial and inconsequential disease. Symptoms such as runny nose, itchy eyes and nose with sneezing and blockage are obviously not life threatening, but affect up to 25% of the population and are the cause of significant disability and cost to society. Patients may also experience fatigue, irritability, as well as mood, cognitive and sleep disturbance in addition to the nasal, ocular and throat symptoms. Allergic rhinitis has important co-morbid associations such as chronic sinusitis, glue ear, asthma exacerbations, nasal polyps, sleep apnoea and dental malocclusion.
SYMPTOMS OF WHAT IS ALLERGIC RHINITIS
Symptoms of allergic rhinitis include
- nasal obstruction or blockage
- nasal itching, sneezing
- postnasal drip that reverse spontaneously or after treatment.
- Allergic conjunctivitis often accompanies allergic rhinitis.
POSSIBLE EFFECTS ON THE FACE DUE TO RHINITIS
- Bluish discolouration of lower eyelids
- Linear Creases under the eyelids
- Allergic inflammation causes congestion in the nose, and this congestion causes poor blood circulation, or “back up” of blood flow in the eye region. This poor blood circulation causes hypoxia in the surrounding tissue. The hypoxia causes a spasm of the Muller’s muscle. Continued spasms result in these under eye wrinkles, or lines.
- Frequent upward rubbing of the nose by either the index finger or the dorsal surface of a fisted hand, in an attempt to relieve itching most often seen in children with allergies
- Horizontal line across the nose because of constant rubbing
TYPES OF ALLERGIC RHINITIS
Seasonal Allergic Rhinitis
- Tree and grass pollens and some fungi trigger seasonal allergic rhino-conjunctivitis (nose and eye allergy) during Springtime and early Summer (March to June).
- Allergy sufferers experience intense nasal and eye itching with explosive sneezing, watery eyes and nose and itchy palate and ears with profuse post-nasal drip.
- Do not develop the typical “allergy face” but have seasonal puffiness of the eyes and eyelids with associated nasal membrane swelling.
Perennial Allergic Rhinitis
- Allergens such as house-dust mite droppings, cat and dog dandruff, horse hair, cockroach droppings result in perennial allergic rhinitis with symptoms all year round.
- These patients are often misdiagnosed as having a “permanent” cold and receive inappropriate treatment with antibiotics.
- Their symptoms can be very subtle and include :
- Constant nasal blockage, snoring at night, watery post-nasal discharge, loss of taste and smell sensation and sneezing only on waking in the morning.
- Coexistent glue ear and chronic sinusitis with nasal polyps are common
ARIA – Allergic Rhinitis and its impact on asthma
- Intermittent allergic Rhinitis
- Persistent Allergic Rhinitis
Nasal hypersensitivity occurs when non-allergenic irritants such as dusts, perfume, tobacco smoke, ozone, sulphur dioxide, nitrogen dioxide, cold air and other environmental pollutants result in increased nasal membrane leakiness, increased nerve excitability, white blood cell infiltrates and more mast cells in the superficial nasal membranes.
These factors lead to an increased nasal irritability to low doses of allergens
CLINICAL EXAMINATION OF ALLERGIC RHINITIS
A/R, Nasal Endoscopy – look for signs of allergic rhinitis, polyps etc.
INVESTIGATIONS AND TESTS FOR ALLERGIC RHINITIS
- Blood Tests – CBC, IgE
- Total Serum IgE
- Allergy Panel Tests
- Skin Scratch Tests
- Nitric oxide (NO)
Total Serum Immunoglobulin E or IgE was the original screening test for allergy, but has been superseded by newer more specific tests. However a Total IgE level exceeding 100kU/l is still highly suggestive of atopy or allergy in adults. Total IgE has a good predictive value in children under 3 years of age and may be used as a screening allergy test in this age-group.
The level of Total IgE depends on the number and size of organs affected by the allergy. For example, a skin allergy results in higher Total IgE than smaller organs such as allergy in the nose.
Levels naturally increase from infancy through to adolescence when they tend to plateau and then slowly decrease towards old age. There is a seasonal variation in Total IgE with levels peaking in spring for pollen allergic individuals.
To confuse matters, Total IgE may also be raised in parasitic infections, some immune diseases, in cigarette smokers, with alcohol consumption and in certain cancers. Total IgE is not therefore 100% specific to allergy.
Allergy Panel Tests
Blood specimens for RAST testing.
The Phadiatop is an excellent screening test for the common inhalant allergens implicated in allergic rhinitis, if this test is positive, individual ImmunoCAP RAST tests are performed to determine the exact inhalant allergen. If food allergy is strongly suspected in children, the Paediatric Food Mix fx5 food screen (cow’s milk, wheat, egg, peanut, fish, and soya) is recommended.
Skin Scratch Tests for the common inhalant allergens are a very simple and cheap to perform and results are immediately available. These include extracts of House-dust mite, Cat, Dog, Mould spores, Grass and Tree Pollen.
Skin tests help to confirm the causative allergen and the “weal and flare” reaction on the skin will demonstrate the inflammatory nature of allergic rhinitis to the patient.
Nasal Mucus Sample
- Take a nasal mucus sample and test for eosinophils using Hansel’s Stain.
- If plenty of eosinophilic white blood cells are present, this helps to confirm the diagnosis of allergic rhinitis.
Sinus x-rays and CT scan – does not help in the diagnosis of allergic rhinitis, but will identify complications such as chronic sinusitis, infections, nasal polyps and sinus fluid levels.
NO gas emission
Nitric oxide (NO) gas levels in air expired from the nasal passages tends to be higher in nasal allergic inflammation. This test is a useful measure of the degree of allergic inflammation, particularly in chronic persistent rhinitis.
Variants of Allergic Rhinitis
In a minority of patients with typical symptoms of nasal allergy, all allergy tests prove negative. We refer to these sufferers as having Chronic Non-allergic Rhinitis or Idiopathic Rhinitis. They are treated in a similar fashion to Allergic Rhinitis using the ARIA Guidelines.
Some have profuse symptoms with eosinophil cells present in their nasal mucus and this condition is termed Non-allergic Rhinitis with Eosinophilia Syndrome (NARES).
TREATMENT FOR ALLERGIC RHINITIS
- Grass pollens can be avoided
- Pets removed from the home and
- Mattresses, pillows and carpets treated to eradicate house dust mites. Use non allergenic material
- If a particular food is implicated in allergic rhinitis, then that food should be excluded from the diet.
- Cigarette smoking should be strongly discouraged in all allergic individuals, as it will only exacerbate symptoms.
MEDICAL MANAGEMENT FOR ALLERGIC RHINITIS
In Perennial Allergic Rhinitis, treatment should to be taken continuously, whilst in Seasonal Allergic Rhinitis treatment only needs to be taken for symptom control during the peak pollen season.
- Intra nasal steroids
- Ipratropium Bromide
- Systemic Steroids
Antihistamines are the mainstay of treatment in seasonal allergic rhinitis. They control the itch, sneeze runny nose and itchy eyes. Older antihistamines such as Chlorpheniramine, hydroxyzine (Atarax) and promethazine (Phenergan) control symptoms, are cheap but have significant sedating side effects.
The newer non-sedating antihistamines are more expensive, cause much less concentration disturbance, can be taken once a day and give good symptom control.
Loratadine, desloratadine, fexofenadine, Mizolastine, Cetrizine , or levocetirizine are all recommended.
Antihistamine sprays such as azelastine may be a useful additional treatment when symptom control of nasal and ocular itching is intractable. They have no effect on nasal blockage and tend to have an unpleasant taste.
Oral decongestants such as pseudoephedrine , phenylepeherine also combat nasal blockage by constricting blood vessels in the nasal membranes and throughout the body to some degree. They therefore may exacerbate blood pressure problems, dry mucus membranes, cause urine retention and trigger glaucoma. Some people are also sensitive to them and experience insomnia, restlessness, headache and palpitations.
Cromolyn in the form of sodium cromoglicate has anti-inflammatory activity and relieves nasal itch, sneezing, mucus production and congestion particularly in seasonal allergic rhinitis. It is an extremely safe product but must be used 4 times a day, and is very effective in the eyes for treating allergic conjunctivitis. Cromolyn’s are a useful option for patients who prefer not to use nasal steroid sprays on an ongoing basis.
Ipratropium bromide is a spray derived from atropine. It provides good relief for the profuse watery nasal discharge including non-allergic or “vasomotor” rhinitis, a particular problem in older males with the so-called “old man’s drip”. Ipratropium is very safe to use, with rapid onset of activity and minimal side effects. It has no effect on nasal blockage, itch or sneezing.
An oral steroid such as Prednisilone is particularly useful in controlling nasal symptoms in allergic rhinitis in cases of emergency (examinations, weddings etc.), and gives rapid relief especially when blockage is severe and intractable. They have significant generalised side-effects and should therefore only be used in severe disease for short periods of 5 to 14 days
Intra nasal steroids
Steroid sprays applied directly to the nasal membranes have revolutionised the treatment of allergic rhinitis – particularly the chronic perennial type. They control the underlying chronic inflammatory process and therefore are the treatment of choice in most patients. These preparations are safe to use for prolonged periods of time at the recommended dosages.
Intra Nasal Steroids
They act on various components of the nasal inflammatory process, causing blood vessel contraction, reducing blood vessel leakiness and reducing inflammatory cell numbers. Nasal steroids such as Flunisolide , Budesonide and Beclomethasone are particularly useful for their preventative effects and newer preparations such as Fluticasone , Triamcinolone and Mometasone can be used effectively on a once daily basis
Nasal steroid sprays also control non-allergic rhinitis and reduce the size of polyps in the nose. Occasionally they may cause local nasal irritation and nose bleeds. They do not relieve palate and eye itch, so antihistamine tablets may also need to be used. If significant nasal obstruction is present at commencement of treatment, then pre-treatment with a decongestant spray will be necessary for a few days.
The leukotriene antagonists Zafirlukast and Montelukast seem to be useful additions in treating allergic rhinitis, especially in aspirin-sensitive people. These products also seem to have beneficial effects in treating patients with asthma and co-existent allergic rhinitis as they block the activity of Leukotrienes in the nasal membranes.
Olopatadine is very effective for eye allergies associated with Hayfever. This eye drop has both antihistaminic and Mast Cell stabilising properties and has a simple twice daily dosage.
TIPS FOR ALLERGIC RHINITIS
- Remain indoors when pollen levels peak and when the grass in being cut.
- Take antihistamines starting two weeks before the pollen season starts.
- Apply a little Vaseline to the lower nostrils to protect and trap pollen grains from entering the upper nose.
- Wash or douche the nasal passages with a dilute salt water solution or use commercial saline sprays available from all chemists .
MORE TIPS FOR ALLERGIC RHINITIS
- When travelling, make sure the car windows are closed and switch on the air conditioning which will filter out pollen grains.
- Wear protective “wrap around” sunglasses to prevent allergic eyes.
- Keep the bedroom windows closed during the day to keep pollen grains out.
- Rather tumble dry washing and do not hang washing outdoors during the day (it acts as a pollen trap).
- Shower and wash your hair in the evening as soon as you return home from work or college to remove all pollen.
- Change into fresh clothes as soon as you return home from work (pollen will have become trapped in your clothes).
- Consider taking a tablespoonful of local honey everyday starting a few months before the pollen season starts - this may act as a form of oral desensitisation (the honey will have been contaminated with pollen)
- Consider using a nasal air filter on high pollen days.