What is Allergic Rhinitis?

Allergic rhinitis or allergic rhinitis refers to allergic rhinitis, which is mainly caused by the release of IgE-mediated media (mainly histamine) after exposure to allergens. Mucosal non-infectious inflammatory disease. There are three necessary conditions for this to happen: specific antigens are substances that cause the body's immune response; atopic individuals are the so-called individual differences and allergies; and specific antigens and atopic individuals meet. Allergic rhinitis is a global health problem that can cause many diseases and loss of labor.

Basic Information

nickname: Allergic rhinitis
English name: allergic rhinitis
Visiting department: ENT

Multiple groups: Elderly people, allergies
Common causes: Induced by the interaction of genes and the environment
Common symptoms: Paroxysmal sneeze, watery snot, stuffy nose and itchy nose

Causes of allergic rhinitis

Allergic rhinitis is a multifactorial disease induced by the interaction of genes and the environment. Risk factors for allergic rhinitis may exist at all ages.

Genetic factor

Patients with allergic rhinitis have atopic constitution and usually show familial aggregation. Some studies have found that certain genes are associated with allergic rhinitis.

2. Allergen exposure

An allergen is an antigen that induces and reacts with specific IgE antibodies. They are mostly derived from animals, plants, insects, fungi or occupational substances. Its constituents are proteins or glycoproteins, and very few are polysaccharides. Allergens are mainly divided into inhaled allergens and food allergens. Inhaled allergens are the main cause of allergic rhinitis.

(1) Mites The main mites in subtropical and tropical areas are house dust mites and dust mites. House dust mites feed on human dander and mainly live on mattresses, bed bottoms, pillows, carpets, furniture, and fluffy toys. It reproduces fastest in hot (above 20 ° C) and humid (more than 80% relative humidity) environments. House dust mite allergens are contained in its excrement particles. When the contaminated fabric is touched, these particles are exposed to the air and can quickly settle again. The mite allergen concentration in the air is related to the onset of allergic rhinitis.

(2) Pollen Wind-pollen pollen can affect people who are hundreds of kilometers away from the pollen source due to its large amount of scattering and its ability to transmit over long distances. Entomogenous pollen is only sensitised by direct contact, such as agronomists and florist shop assistants. The allergenic ability of pollen varies with season, geographical location, temperature and plant species. Most people who are allergic to pollen suffer from conjunctivitis.

(3) Animal dander Animal dander and secretions carry allergens. Cat and dog allergens are widely found in indoor dust and furniture decoration.

(4) The fungal allergen mold releases allergenic spores into the indoor and outdoor environment, and the humid and hot environment grows rapidly.

(5) Cockroach allergens Allergens are found in their faeces and carapace. The particles are large and do not spread in the air.

(6) Food allergens Food allergic reactions are rare when allergic rhinitis is not accompanied by other systemic symptoms. On the other hand, food allergies are common in patients with multiple organ involvement. For infants, most are caused by milk and soy; common food allergens for adults include: peanuts, nuts, fish, eggs, milk soy, apples, pears, and so on.

Clinical manifestations of allergic rhinitis

The typical symptoms of allergic rhinitis are paroxysmal sneezing, watery snot, nasal congestion and itching. Some are accompanied by hyposmia.

Sneeze

Paroxysmal attacks occur more than 3 times a day, often in the morning or at night or immediately after exposure to an allergen.

2. Clean your nose

A lot of watery noses can sometimes drip from your nostrils unconsciously.

3. Nasal congestion

Intermittent or continuous, unilateral or bilateral, varying degrees of severity.

4. Itchy nose

Itchy nose in most patients, hay fever can be accompanied by itchy eyes, ear itching and itching.

Allergic rhinitis examination

Physical sign

Nasal mucosa is pale, edema of both inferior nails, and clear or sticky nasal discharge can be seen in the total nasal passages and nasal floor.

2. Skin prick test

Use a standardized allergen reagent to puncture the skin on the palm of the forearm and observe the results 20 minutes later. Each test should be performed with positive and negative controls, with histamine as the positive control and allergen vehicle as the negative control. Determine the results according to the corresponding standardized allergen reagent instructions. Skin prick tests should be performed at least 7 days after discontinuation of antihistamines.

3. Serum-specific IgE detection

The patient's venous blood is drawn for immunological testing, and is not affected by drugs and skin conditions. The diagnosis of allergens for allergic rhinitis requires a comprehensive history of clinical manifestations, skin puncture tests, and serum-specific IgE test results.

4. Nasal challenge test

It is the gold standard for the diagnosis of allergic rhinitis, but it has risks and is not clinically used as a routine method.

Allergic rhinitis diagnosis

Clinical symptoms Symptoms such as sneezing, watery snot, nasal congestion, and itchy nose appear more than 2 items (including 2 items), and the symptoms persist or accumulate more than 1 hour per day. May be accompanied by eye symptoms such as itchy eyes and conjunctival congestion. Signs are usually pale nasal mucosa, edema, and nasal watery secretions. Allergen skin prick test is positive, and / or serum-specific IgE is positive. Nasal challenge test may be performed if necessary.

Differential diagnosis of allergic rhinitis

Allergic rhinitis needs to be distinguished from acute rhinitis catarrhal phase, cerebrospinal fluid rhinorrhea, and vasomotor rhinitis.

Allergic rhinitis complications

The diseases associated with allergic rhinitis can be divided into the same pathogenic pathway (such as allergic reactions) or combined with other diseases (mucosal swelling, co-infection caused by mucus retention). Including asthma, conjunctivitis, chronic rhino-sinusitis, adenoidal hypertrophy, secretory otitis media, etc. The presence of allergic rhinitis exacerbates asthma, and most patients with asthma suffer from allergic rhinitis. Outdoor allergens are more likely to cause allergic conjunctivitis than indoor allergens.

Allergic rhinitis treatment

1. Avoid contact with allergens

(1) Reduce the number of indoor dust mites; maintain the relative humidity of the living space below 60%, but too low (such as less than 30% to 40%) will cause discomfort; clean the carpet; clean bedding, curtains, mite allergen Soluble in water, washing textiles can remove most of the allergens; use air purifiers and vacuum cleaners with filters.

(2) Corresponding pollen sensitization season, avoid allergens.

(3) Patients who are allergic to animal fur should avoid allergens.

2. Drug treatment

The following factors should be considered: efficacy, safety, cost / effect ratio, etc. Intranasal and oral administration are commonly used, and efficacy may vary between patients. There is no long-term sustained effect after discontinuation of the drug, so maintenance treatment is needed for persistent allergic rhinitis. Prolonged treatment does not occur with rapid drug resistance. Intranasal administration has many advantages. High-concentration drugs can directly affect the nose, avoiding or reducing systemic side effects. However, for patients with other allergic diseases, drugs need to act on different target organs, and intranasal administration is not the best choice. Systemic drug treatment is recommended. Various drugs should be used with caution during pregnancy.

(1) Antihistamines: Oral or nasal second-generation or new H1 antihistamines can effectively relieve symptoms such as nasal itching, sneezing and runny nose. Suitable for mild intermittent and mild persistent allergic rhinitis, combined with nasal glucocorticoids for the treatment of moderate-severe allergic rhinitis.

(2) Glucocorticoid Nasal glucocorticoid can effectively alleviate symptoms such as nasal congestion, runny nose and sneezing. Oral glucocorticoids can be used for short-term treatment of severe patients who do not respond to other medications or cannot tolerate nasal medications.

(3) Anti-leukotriene drugs are effective for allergic rhinitis and asthma.

(4) Chromones are effective in alleviating nasal symptoms, and eye drops are effective in alleviating ocular symptoms.

(5) Intranasal decongestant can relieve the symptoms of nasal congestion caused by nasal congestion, and the treatment course should be controlled within 7 days.

(6) Intranasal anticholinergic drugs can effectively suppress runny nose.

(7) Chinese medicine part Chinese medicine is effective in relieving symptoms. Children and the elderly are treated the same way as adults, but special care should be taken to avoid adverse drug reactions.

3. Immunotherapy

Immunotherapy induces clinical and immune tolerance, has long-term effects, and prevents the development of allergic diseases. Allergen-specific immunotherapy is commonly used subcutaneously and sublingually. The course of treatment is divided into a dose accumulation stage and a dose maintenance stage, and the total course of treatment is not less than 2 years. A standardized allergen vaccine should be used.

(1) The indication is mainly used in patients with allergic rhinitis who have failed conventional drug treatment.

(2) Contraindications during asthma attack; the patient is using beta receptor blockers; combined with other immune diseases; pregnant women; patients can not understand the risks and limitations of treatment.

Immunotherapy may have local and systemic adverse effects.

4. Surgical treatment

Its indications are that the symptoms of nasal congestion are not improved by drugs or immunotherapy, and there are obvious signs that affect the quality of life; there are obvious anatomical variations in the nasal cavity with dysfunction; combined with chronic rhino-sinusitis, nasal polyps, drug treatment is ineffective. Surgical treatment is not a routine treatment for allergic rhinitis.