Pathology of allergic rhinitis

2021-01-31 12:00 AM

In terms of the biochemistry of nasal mucus, special substances such as enzymes, which are able to dissolve the shell of some bacteria, inhibitors of protein-digesting enzymes


Allergic rhinitis is a fairly common disease in the world as well as in Vietnam. According to epidemiological reports, the prevalence of allergic respiratory diseases accounts for 10-15% of the world's population. Vietnam allergic rhinitis accounts for about 32% of diseases of the ear, nose and throat.

Today, the climate is increasingly harsh, the environmental pollution is increasing, so the rate of allergic diseases also increases.

Causes and mechanisms of the disease

Allergic rhinitis is an immune disease. Caused by foreign allergens and the main path of entry is nasal mucosa

Immune problems in the nose

In normal people in the nose and throat always have symbiotic bacteria and some common pathogenic bacteria such as pneumococcus, streptococcus, Hemophilus influence ... The reason we don't get sick is thanks to the immune system. are very effective: the local and systemic immunity specific and nonspecific humours and cells work together very closely.

The role of the outer ring of the epithelium.

The epithelium is actually a barrier protecting the nasal mucosa against the invasion of pathogens from outside such as bacteria, viruses, allergens ... thanks to the purification of the hair mucous system, the elements do not stay in contact with the mucosa for a long time and are pushed down the throat.

Biochemistry of nasal mucus contains special substances such as enzymes, capable of dissolving the sheath of some bacteria, substances that inhibit the enzyme secreted by bacteria, protect the secreted IgA (IgA-s). from being destroyed. In addition, the role of IgA-s (IgA-secretion) and other ingredients contribute to inhibiting the destruction of microorganisms that increase the clearance effect of the nasal mucosa.

The role of the submucosa.

The submucosa is the second line of defence. There are many different mechanisms of action (biochemistry, immunity ...) that are closely associated with specific in situ immunity. Polymorphonuclear leukaemia and macrophages are more active by complement and Opsonin. Normally, the role of humoral and local cellular immunity takes over, but when the nasal mucosa is inflamed, the main role is the serum immunoglobulins that escape through the vessel wall to protect.


Due to allergen exposure.

Home dust airway allergens, animal hairs, pollen ...

Food allergies: eggs, milk, seafood (shrimp, crab, jelly ...).

Allergens are drugs: antibiotics of all kinds.

Atopic (Atopic).

Allergic conditions such as allergic rhinitis, bronchial asthma and neonatal eczema are characterized by family characteristics and inheritance.

Hypersensitivity: each body also has a basic role, before the same allergen phenomenon occurs or not and reacts strongly or mildly.

Diagnosis of allergic rhinitis

There are many diagnostic methods, but mainly the following methods:

Take a history of allergy

This is a very important method that is easy to follow and is the first in diagnosing an allergy that helps to target one type or group of allergens as the cause.

The purpose of exploiting an allergy history is to:

Preliminary determination of the allergen that causes the disease can exploit the history of allergy in printed form.

Family history: parents, siblings, children, relatives with allergic diseases.

Personal history: conditions such as urticaria, allergic bronchial asthma, food allergy eczema, drug allergy, facial oedema when exposed to chemicals, paint.

Clinical examination

Must ask carefully when the illness is favourable such as cold, flu, changing weather, living and living conditions.

Mechanical symptoms: prolonged sneezing into the colon wall, clear runny nose, when nasal congestion occurs (conditions appear sporadic or persistent). Which of the three symptoms above is the most uncomfortable for the patient (is the main symptom)?

Physical symptoms:

Mucosal condition: pale colour, oedema.

Nasal occlusion: can be degenerative, overgrowth. The resilience of vasoconstrictor drugs, nasal fluid is initially in, and then cloudy.

There may be polyps or degenerative middle rhinoplasty like polyps.


Test nasal fluid cells for Eosinophil (Eo) leukocytes.

The result is considered positive when the leukocyte ratio is> 1%.

Test for detecting allergy IgE antibodies: with house dust allergen in patient serum by Mastocyte decomposition reaction according to Ishimova-LM method.

Direct quantification of IgE antibodies: total serum by ELISA-labeled immunological technique (Enzyme-Linked ImmunoSorbent Assay).

Total IgE concentration in UI units or ng / ml

Negative (-) <10 UI

Doubt ( ± ): 10-100 UI

Positive (+)> 100 UI

(1UI = 2,4ng/ml IgE)

Peripheral Blood Waist Leukaemia

Peripheral leukaemia count.

The result is considered to be increased when the WBC ratio is> 3.5%.

Skin tests: is a method of detecting the sensitization of the body by transdermal multiple allergens and then evaluating the size and characteristics of papules and local inflammatory reactions. An allergen that results in a positive skin test can be considered a cause when combined with a history of allergy having consistent results. If this result is not available and the skin test is questionable, a stimulant test should be performed.

The stimulatory test is the ability to biologically diagnose allergic reactions whose basis is to reproduce this reaction by introducing the suspected allergen into the body in order to reproduce a lifelike clinical condition if the reaction is positive. calculation occurs.

Allergic rhinitis forms

Seasonal rhinitis

Common in young people, large children, rare in the elderly, with family factors, clear heredity.

Allergens are usually pollen with the typical spring allergic rhinitis with herbaceous allergens.

Typical symptoms: sneezing, a clear runny nose, nasal congestion occurs only 7-15 days, often accompanied by watery eyes, conjunctivitis, allergic lower respiratory tract causing difficulty breathing, bronchial asthma but No skin rashes, itching.

Rhinitis year-round

Frequent relapses, year-round, also often have a family element

The allergen is very diverse: it is common to encounter house dust, mould, and so on, sometimes cannot be identified.

Atypical symptoms such as seasonal rhinitis, nasal congestion is the most common and bothersome symptom, sometimes having a runny nose down the arch.

Occupational rhinitis

When it occurs with special allergens in the production working environment.

Often referred to as an occupational disease. Typical symptoms: sneezing, runny nose is common, in some people with low fever, cough, chest tightness or an asthma attack.


Allergic attacks usually last a few days, then go away on their own with no treatment. The attack will always recur with time, with age, with exposure.

Some cases are only localized in the nose, many cases occur simultaneously in the sinuses, progressing for a long time will cause nasal polyps or sinuses.

In infectious conditions, allergic rhinitis weakens prone to infectious sinus rhinitis.

Treatment of allergic rhinitis

To treat allergic rhinitis, first of all, all allergens that cause disease must be eliminated from the patient's living environment (but very difficult), so we have to pay in part or change the patient's immune response. Through immunological measures, this measure is called desensitization. The treatment schemes for allergic rhinitis, which physicians are ranked in order. If specific conditions permit, then preference is given to etiologic therapy before symptomatic therapy in the following order:

Treatment of the cause (clearing of the allergen).

Treatment of hypersensitivity solution.

Corticoid therapy.

Use an antihistamine.


Surgery to solve nasal cavity malformations.

Payment of allergens

This means complete separation of the allergens diagnosed as causing the pathogen from the patient's environment or the patient avoiding the site of the pathogen if this is achieved then that is the best form of treatment.

Partial allergen elimination: it is difficult to implement partial allergen elimination method for allergens present in the house such as house dust, fungus ... but reducing the number of allergens also improves the result. results of treatment.

Specific desensitization solution

This is immunotherapy, which desensitizes the patient's immune system facing known pathogens.

Symptomatic treatment

It is drug therapy. Only used when the treatment methods for the above-mentioned cause do not help or cannot conduct treatment according to the cause, we use antihistamines, which inhibit the release or synthesis of intermediate chemicals. cause an allergic reaction.

In severe levels, they can use corticosteroids. In addition, in folk, they also use medicinal plants such as honeysuckle, horse head, hay in the treatment of allergic rhinitis.