| ID | 83 |
|---|---|
| Name | ALLERGIC RHINITIS (HAY FEVER) |
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| Diagnosis | |
| Investigations | |
| Management | |
| Introduction | Allergic rhinitis is a common cause of nasal inflammation and congestion in our population. It may be seasonal or year-round problem in different class of people. Seasonal allergic rhinitis is most commonly caused by pollens and spores. Dust, household mites, air pollution, and pet dander may produce year-round symptoms, known as ‘perennial rhinitis.’ The mechanism of allergic rhinitis in a predisposed individual starts by exposure to an akborne allergen. This activates both humoral (B-cell) and cyotoxic (T-cell) immune systems with subsequent allergen-specific IgE responses, which inturn cause release of inflammatory mediators. The response is increased when antigen is passed to regional lymph nodes and activates more T-cells. Interleukin and cytokine release causes specific activation of mast cells, eosinophils, plasma cells, basophils and other T-cells. Many of these circulating cells then migrate into the nasal and ocular epithelium, where they release proinflammatory mediators viz, histamine, prostaglandins, and kinins, which lead to manifest symptoms. |
| History | |
| Etiology | |
| Clinical Features | Clinical features: 1. Sudden onset of symptoms with tickling and burning sensation in the nose & sneezing; profuse watery nasal discharge; malaise, sore throat, slight rise of temperature; head feeling ‘stuffed’. The symptoms are usually persistent but may vary with season changes. 2. Ocular symptoms are often seen with nasal inflammation, such as- eye i irritation, pruritus, conjunctival erythema, and excessive eye discharge. 3. There may be strong family history of allergy. 4. On examination, the mucosa of the turbinates is usually pale or violaceous (due to venous engorgement). 5. In patients with long-standing allergic rhinitis, yellowish boggy nasal polyps may develop. |
| Preventions | |
| Treatment | Treatment: 1. Antihistamines: For immediate releive of symptoms: Low cost older sedating antihistamines- i. Brompheniramine or chlorpheniramine, 4mg orally 6-8 hourly, or 8-12mg orally 12 hourly (as a sustained-release tablet); or ii. Clemastine 1.34-2.68mg orally twice daily; iii. Loratadine may be an exception, which is less sedating and can be given 10mg orally once daily. The newer antihistamines with minimum sedation- i. Cetirizine 10mg orally once daily; or, ii. Desloratadine (H,-receptor antagonist) 5mg orally once daily. Nonsedating antihistamine, iii. fexofenadine (Hrreceptor antagonist) 60mg orally twice daily or 120mg once daily. Other newer antihistamines found effectived in randomized trials- iv. ebastine 10-20mg orally once daily; v. misolastine 10mg once daily, vi. levocabastine nasal spray 0.2mg twice daily; vii. azelastine two sprays per nostril (l.lmg/day). In case of perennial allergic problems, where long-term treatment is required, there is every chance of antihistamine tolerance development, effective antihistamines should be given periodically alternatingly. 2. Intranasal corticosteroids therapy: Corticosteroids as nasal sprays are more effective in the treatment of allergic rhinitis. i. beclomethasone spray (42mcg/spray) twice daily per nostril; ii. flunisolide spray (25mcg/spray) twice daily per nostril; iii. mometasone furoate spray (200mcg/spray) once daily per nostril; iv. budesonide spray (100mcg/spray) twice daily per nostril; and v. fluticasone propionate spray (200mcg/spray) once daily per nostril. All intranasal corticosteroids are considered equally effective, although the synthetic (budesonide and fluticasone) corticosteroids appear to have higher topical potencies. 3. Other adjunctive therapies: Leukotriene receptor antagonists, such as montelukast 10mg daily orally alone or with antihistamine (cetirizine 10mg daily orally or loratadine 10mg daily orally) may improve nasal rhinorrhea, sneezing, and congestion in allergic rhinitis. Mast cells stabilizer cromolyn sodium and sodium nedocromil are also useful in allergic rhinitis (but, less effective than corticosteroid sprays). Anticholinergic preparations, such as ipratropium bromide 0.03% or 0.06% sprays 3 times daily in each nostril may be helpful in controlling nasal rhinorrhoea in allergic rhinitis (but, less effective than corticosteroid sprays). 4. Preventive & environmental measures: i. Avoid exposure to airborne allergens, ii. Maintaining an allergen-free environment by covering pillows and mattresses with plastic covers or using synthetic materials (foam mattress, acrylics) rather than animal products (wool, horsehair), and removing dustcollecting household materials (carpets, drapes, bedspreads, wicker etc.); air purifiers and dust filters may also be used in maintaining an allergen-free environment, iii. Nasal saline irrigations can help effectively in flushing out the allergens from the nasal cavity. 5. Immunotherapy: In patients where medical and preventive therapy fails to control allergic rhinits symptoms adequately, immunotherapy may be considered. But, before that proper identification of causative allergens is essential. Treatment should be given at a suitable medical centre with monitoring facilities following treatment because of the risk of anaphylaxis during dose escalation. Local reactions are common and usually self-limited. Treatment should be continued with maintenance dose administration for a period of 3-5 years. Immunotherapy improves allergic rhinitis and reduces the need for medical treatment, and also reduces circulating IgE in the patients blood. |
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