Allergic rhinitis (AR) is the non-infectious inflammation of nasal mucosa, a Type I hypersensitivity disease mainly mediated by immunoglobulin E (IgE) after the body is sensitized by allergens. The significant rise in the prevalence of AR in China is closely related to living environment, climate and lifestyle. AR can not only lead to low learning and work efficiency and sleep disorders, but also cause mental problems that seriously affect the physical and mental health of patients (especially children).
Here are some key messages on diagnosis and treatment of AR, based on the Chinese Guidelines for the Diagnosis and Treatment of Allergic Rhinitis (Revised Edition 2022) and the Guidelines for the Diagnosis and Treatment of Allergic Rhinitis in Children (Revised Edition 2022) released in May 2022.
Preventive measures for allergic rhinitis
Developing a comprehensive environmental control scheme is an important way to avoid or reduce exposure to known allergens, irritants and air pollutants (such as PM2.5, automobile exhaust and indoor organic volatiles).
AR is mainly caused by various types of airborne sensitized pollen, including tree pollen in early spring, herbage pollen prevalent in late spring and weed pollen in summer and autumn.
After the Start of Autumn every year (one of the 24 solar terms in the Chinese Lunar calendar), a large number of artemisia, humulus and ragweed pollen are scattered in northern China, causing very serious allergic rhinitis and even bronchial asthma.
The symptoms of many AR patients can be significantly improved by taking the following measures:
People allergic to pollen should wear protective masks and goggles during outdoor activities.
To deal with dust mites (including house dust mites and tropical mites), measures such as controlling indoor temperature and humidity, reducing food sources and living areas of dust mites, physical isolation with dust mite prevention materials and frequent cleaning of air-conditioning filters should be taken for prevention and control.
Those who are allergic to pet dander, such as cat and dog hair, should not keep pets.
Proper medical treatment
Medical treatment, especially proper medication, is the main method of treating allergic rhinitis.
Glucocorticoid is the most effective anti-inflammatory medicine at present. Using glucocorticoid spray in the nasal cavity is the first choice for patients with moderate and severe persistent allergic rhinitis. Continuous treatment is necessary and the course of treatment should usually last for 4 to 12 weeks.
Antihistamines (H1 receptor antagonists) and anti-leukotrienes (leukotriene receptor antagonists) are also among the first choices for the treatment of allergic rhinitis. For the treatment of allergic rhinitis in children, it is recommended to use second-generation antihistamines without the side effect of drowsiness to avoid inhibition of the central nervous system, which may damage cognitive functions.
The efficacy and safety of some new second-generation oral antihistamines have been demonstrated in children older than six months. Anti-leukotriene medicine can significantly improve the quality of life for patients with AR and asthma.
In short, for AR patients with mild symptoms and intermittent attacks, using glucocorticoid spray, antihistamines or anti-leukotrienes can achieve satisfactory results, but for moderate and severe persistent AR sufferers, it is recommended to add antihistamines and antileukotrienes to the nasal spray to enhance the treatment effect.
Desensitization treatment for children
In addition to the symptomatic treatment mentioned above, we should pay more attention to immunotherapy. Allergen immunotherapy, commonly known as "desensitization therapy", is the only causal treatment for type I hyper-sensitivity diseases such as allergic rhinitis and allergic asthma.
Desensitization therapy refers to the special allergen vaccine (given by subcutaneous injection or sublingual administration). As the dose increases, it can produce immunomodulatory effect and rebuild the immune tolerance function of the body.
Early desensitization in children can block the further development of asthma and produce long-term effects.
However, there are currently few varieties of standardized allergen vaccines, only some desensitizers for house dust mite and dust mite available for clinical use, which restricts the popularization of desensitization therapy.
In 2021, domestically-produced artemisia annua pollen allergen sublingual drop was officially approved for clinical use, which is good news for patients suffering from autumn artemisia pollen allergy in northern China.