Allergic rhinitis (AR) in children is a common disease in otolaryngology and is classified into perennial and seasonal allergic rhinitis (i.e., “hay fever”), the onset of which is related to genetic factors, environmental factors and allergen exposure, and there is no major difference in treatment between the two. In 2008-2009, the self-reported prevalence of allergic rhinitis was 14.5%, 20.4% and 7.8% in Beijing, Chongqing and Guangzhou, respectively, in a questionnaire survey of children aged 0-14 years.
Etiology
1. Genetic factors: Some of the affected children are allergic due to their family genes.
2, environmental factors: allergens are divided into inhalation and ingestion.
Inhalant allergens include dust mites, molds, animal dander, insects and pollen, as well as particles of atmospheric pollution, exhaust fumes from cars and formaldehyde emitted by decoration materials. Dust mites are found wherever people live. Plush toys, quilts, bed sheets, pillows, cloth sofas, carpets, clothing and air conditioning filters are all places where mites hide.
② Ingested allergens include milk, fish and shrimp, seafood, eggs, peanuts, soybeans, flour, and medications.
Generally, inhalant allergens are the most common. Parents need to pay attention to the specific allergens to which their children are allergic, and observe under what circumstances their children are prone to develop symptoms, so that they know what they are allergic to.
Clinical manifestations
There are four typical symptoms: paroxysmal sneezing, runny nose, itchy nose and nasal congestion. In addition, eye symptoms may be present: itching, tearing, redness and burning sensation. Sneezing is often worst in the morning, clear watery mucus may trigger coughing and throat clearing, and nasal congestion may change with position, from left-sided to right-sided.
Anterior rhinoscopy shows bilateral pale and swollen nasal mucosa, edema of the inferior turbinates, and a lot of watery nasal secretions. In case of co-infection, the mucosa is congested and the bilateral inferior turbinates are dark red with mucopurulent or purulent secretions. In children with a long history of recurrent and poorly controlled symptoms, polypoid changes and mucosal hypertrophy of the turbinates are seen. In addition, the following tests can be done to determine the diagnosis.
① Skin prick test (a small amount of highly purified allergen liquid is put on the forearm of the child, and then a painless prick needle is gently pricked into the skin surface), this method has high sensitivity and high specificity, generally above 80%, and is commonly used in clinical practice, requiring the discontinuation of antihistamines (such as loratadine, etc.) 1 week before the test.
②Serum specific IgE test (blood sampling, no need to stop medication).
③Nasal mucosal excitation test (usually rarely done in clinical practice nowadays).
Some children whose main symptoms are episodic sneezing and large amount of clear snot, but negative allergen test and normal eosinophil count in routine blood test, are suffering from vasomotor rhinitis, the etiology of which mainly includes cold air, strong odor, sports, etc. The symptomatic treatment is similar to that of allergic rhinitis.
Allergic rhinitis in children can lead to the following complications.
(i) allergic sinusitis or nasal polyps.
(ii) Upper airway cough syndrome.
(iii) Allergic conjunctivitis.
④secretory otitis media.
⑤ bronchial asthma.
⑥Obstructive sleep apnea hypoventilation syndrome.
Treatment
The main treatment methods are drug therapy and allergen-specific immunotherapy (i.e., desensitization). Although this disease cannot be completely cured yet, through standardized comprehensive prevention and treatment, the various symptoms of children can be well controlled and the quality of life can be significantly improved.
I. Drug therapy (considering the degree of parental acceptance, only the most commonly used drugs are listed below)
First-line drugs (recommended): nasal glucocorticoids, nasal or oral antihistamines, oral leukotriene receptor antagonists.
Second-line drugs (used as appropriate): nasal decongestants, etc. In addition there are herbal medicines and nasal rinses.
Nasal glucocorticoids include.
Mometasone furoate, fluticasone propionate, budesonide. Generally nasal spray 1-2 times a day, the course of treatment is not less than 2 weeks; it is best to use in the morning, the morning spray hormonal drugs and the body hormone secretion time is relatively consistent, can greatly reduce the side effects. It is the drug of choice for moderate to severe persistent AR, and the course of treatment is 4 weeks or more. It has a significant improvement on all nasal symptoms in children with AR, and is currently the most effective drug for the treatment of AR. It is safe and well tolerated, and some studies have reported that a one-year course of treatment has no significant effect on the overall growth and development of children.
Nasal antihistamines include.
Azelastine and levocabastine. They are usually administered twice daily for a course of not less than 2 weeks. Their efficacy is equivalent or better than that of second-generation oral antihistamines, especially for relief of nasal congestion. Some studies have shown that the combination of nasal antihistamines and nasal glucocorticoids is fast-acting and effective in the treatment of moderate-to-severe AR.
Oral second-generation antihistamines include.
Levocetirizine, cetirizine, loratadine, and desloratadine. They are usually taken once a day for at least 2 weeks. They have a good safety profile, are fast-acting, have a long duration of action, provide significant relief of nasal symptoms, and are effective for combined ocular symptoms, but have limited effect on improving nasal congestion.
Oral anti-leukotrienes include.
Montelukast. The drug is administered once daily, orally at night before bedtime, for a course of 4 weeks or more. It is safe and well tolerated, provides effective relief of nasal and ocular symptoms, and is superior to second-generation oral antihistamines in improving nasal congestion, and is more effective when used in combination with the latter.
Nasal decongestants include.
Cyclozoline, Hydroxyzoline, Ephedrine (not used in children). Use as appropriate! Strictly control the number of times of use and the course of treatment, generally nasal spray 2-3 times a day, continuous use for no more than 7 days, if you really need to continue to use should stop 3 days and then use again, still no more than a week. It is only suitable for children with allergic or acute rhinitis attack, nasal turbinates with high edema leading to complete blockage of nasal cavity or sinusitis, the purpose is to contract the nasal mucosa blood vessels to facilitate the discharge of nasal mucus in the nasal cavity or sinuses, which can quickly relieve nasal congestion, but has no significant improvement effect on other symptoms of AR. Excessive duration of treatment or too frequent use of the drug may lead to rebound nasal congestion and prone to drug rhinitis. prohibited in children under 2 years of age.
Chinese herbs.
Studies have shown that herbal medicines are effective in improving the nasal symptoms of perennial and persistent AR and have a good safety profile.
Nasal irrigation.
The use of physiological sea (saline) water can remove intranasal irritants, allergens and inflammatory secretions, reduce nasal mucosal edema and improve mucociliary clearance.
II. Surgical treatment
The efficacy of surgery has been unsatisfactory, and children under 18 years old are contraindicated.
Immunotherapy (commonly known as desensitization therapy)
Allergen-specific immunotherapy is the first-line treatment for AR and is clinically recommended. This therapy gives the child allergen extracts (e.g., dust mite drops, which are a therapeutic vaccine) to induce the body to achieve immune tolerance. Both methods have their advantages and disadvantages. The former has fewer side effects, is safe, and its efficacy is statistically comparable to that of the latter. Immunotherapy can be used in patients with a clear clinical diagnosis of AR without the prerequisite of ineffective drug therapy. According to the opinion of the World Metabolic Organization, there is no specific age limit for sublingual immunotherapy, but it is recommended in China for people over 3 years of age.
Sublingual immunotherapy is relatively easy to administer through the oral mucosa and is safe and well tolerated, and can be self-administered at home under the guidance of a physician. The local reactions of sublingual immunotherapy are mainly itching, redness and swelling under the tongue, and abdominal pain and diarrhea may occur after swallowing the drug. If local reactions occur continuously, it indicates that the treatment dose is too high, and it is necessary to consider reducing the dose and providing local symptomatic treatment. The incidence of systemic adverse reactions is low and the severity is mild, divided into four grades, of which mild is local urticaria, rhinitis or mild asthma, and the most serious consequence can be anaphylaxis. Systemic reactions have been reported in 5.6 per 10,000 patients treated, and only 1.4 serious adverse reactions per 100,000 sublingual doses. To date, no cases leading to death have been reported in the clinical application of sublingual immunotherapy in China or abroad.
The incidence of systemic reactions to subcutaneous immunotherapy in China is 47 per 10,000.
Treatment of adverse reactions: Mild local reactions generally do not require treatment, and oral antihistamines can also be used as appropriate. If the systemic reactions are mild-moderate, immunotherapy can be continued after symptomatic treatment, but the dose needs to be adjusted.