Pollen allergy

Pollen allergy is a disease associated with seasonal natural phenomena, the flowering of cereals, trees, and various grasses. The disease develops as a response to the secondary invasion of an allergen in those who already have a predisposition to allergies. There are several synonyms that define the disease, which sometimes mislead allergy sufferers themselves.

Pollen allergy is pollinosis, hay fever, seasonal allergic conjunctivitis, rhinoconjunctivitis. All the diversity of concepts is reduced to one term, designated in the classifier of diseases, ICD-10, where pollen allergy is code J30.1 - allergic rhinitis caused by plant pollen.

1. Among all types of allergies, hay fever is considered the most common and is diagnosed in 20-25% of the world's population.
2. Pollen allergy was first recognized as an independent disease only in 1819.
3. Initially, it was believed that dry grass and hay provoked allergic reactions, which is where one of the names for allergies came from – hay fever.
4. Of the great variety of plants found on the planet, only slightly more than 50 families can cause allergies. These include the so-called carminative flora, that is, plants that produce pollen that is carried several kilometers by the wind.

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Causes of pollen allergy

The etiology of pollinosis, that is, the causes of pollen allergy, is a whole series of biochemical reactions, when histamine and other substances enter the bloodstream, provoking an inflammatory process and the secretion of mucous secretions from the eyes and nose. The factor causing a hypertrophied immune response is the male components of pollen, which can be secreted by cereals, some types of trees, weeds and herbs. Allergies are provoked only by pollen that meets certain parameters, outlined in the studies of the famous allergist Thommen:

• Large amount of pollen.
• Volatility and the ability to quickly spread throughout the surrounding area (usually such pollen is produced by anemophilous plants).
• Immunogenic properties of male pollen particles due to the presence of polypeptides and glycoproteins.
• Distribution of the plant in the area.

The causes of pollen allergies in the spring can be explained by the release of allergens by birch, oak, maple, hazel, sycamore, and poplars (the fluff absorbs and carries pollen from other trees).

The second peak of the disease is associated with the summer period, when wild plants (grasses) and cereals – corn, rye, buckwheat – begin to bloom.

The third period of pollen allergy is autumn, which is known for its sad statistics of violent allergic reactions to ragweed, which begins to bloom in August. The number of diagnosed asthma attacks, Quincke's edema and anaphylactic shocks increases sharply in late summer and autumn, and this is due to the flowering of ragweed, which is considered the most aggressive plant in terms of provoking allergies.

Flowering wormwood and quinoa also cause a lot of trouble for allergy sufferers.

In addition, the etiology of pollinosis is characterized by the fact that many plants have antigenic similarities with each other, with fruits, vegetables, melons, and cause polyvalent allergies, which do not have one specific pathogen.

Factors that can provoke cross-pollinosis: Pollen Related plants, trees, flowers, meadow grasses Fruits, vegetables, melons, nuts, products Medicinal herbs Pollen of flowering birch Apple tree, hazelnut - hazel, alder Hazelnut, carrot, apple, plum, potato, cucumber, celery, tomato, onion, kiwi, peaches Birch buds, alder cones, hazelnut leaves Cereals - buckwheat, rye, corn, wheat, oats, barley Not detected Not detected Not detected Flowering wormwood Sunflower pollen, dandelion Sunflower vegetable oil, products containing it, citrus fruits, honey and chicory Chamomile, elecampane, coltsfoot, calendula, string, celandine Ragweed Sunflower Bananas, sunflower oil, seeds, melon Dandelion Quinoa Not found Beetroot, rarely – carrots, spinach Not found

The causes of pollen allergy in terms of the aggressiveness of provoking factors are distributed as follows:

1. Weeds, herbs.
2. Cereal crops.
3. Pollen trees.

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How does an allergen enter the body?

The immunogenicity of pollen depends on its structure and properties, especially on its solubility. Since the molecular weight of pollen elements is quite large and reaches 40,000 daltons, the immune system quickly recognizes pollen as a foreign component and actively fights it. It should also be taken into account that most of the structural substances of pollen are not able to dissolve and do not pass the barrier of mucous membranes, but the smallest pollen proteins easily overcome the protection of the mucous membrane and enter into aggressive interaction with human lymphocytes, provoking an allergic reaction. Intensive activity of the immune system, its immediate response to the invasion of an allergen leads to the fact that the release of histamine contributes to a sharp narrowing of the bronchi, blood flows to the mucous membranes - this is how a typical persistent allergic cough occurs, often ending in an asthma attack, itching, allergic lacrimation and nasal discharge appear.

Symptoms of pollen allergy

The clinical manifestations of pollinosis are typical, although some variants of hay fever may be similar to the manifestations of acute respiratory diseases.

Symptoms of pollen allergy are characterized by a clinical triad:

1. Nasal and ophthalmological (rhino-conjunctival) symptoms – difficulty breathing, nasal congestion, lacrimation.
2. Nasal discharge that is not typical for acute respiratory infections is rarer in consistency and more frequent.
3. Persistent sneezing, attacks can number up to 20-25 times per minute.

In addition, the clinical picture of pollinosis includes the following symptoms:

• Severe itching, most often in the nasopharynx and eye area.
• Purulent conjunctivitis associated with secondary bacterial infection (rubbing of inflamed eyes).
• Pain, sand in the eyes, photophobia, swelling of the eyes.
• Noise, stuffiness in the ears.
• Attacks of bronchial asthma associated with seasonal factors (diagnosed in 20% of allergy sufferers).
• Allergic dermatitis.

It should be noted that the symptoms of pollen allergy appear only during the flowering period of trees, plants and grasses. As soon as the season that provokes the reaction ends, the main symptoms disappear. The severity of clinical manifestations depends on the level of concentration of the allergen, i.e. pollen, as well as on the degree of a person's predisposition to allergies. In sensitive people, the symptoms may persist for a long time even after the end of the flowering season.

In severe cases, inflammatory processes of the genitourinary organs may develop - cystitis, vulvitis, but these diseases also quickly pass along with the main symptoms of pollinosis. The most serious manifestation of pollen allergy is Quincke's edema and anaphylactic shock.

Birch pollen allergy

An allergic reaction to birch blossoms from mid-April to late May is a real disaster for allergy sufferers. According to statistics provided by the WHO, birch pollen allergy affects more than 100 million people annually.

Birch is associated with health, indeed its buds, leaves and even pollen can become a medicine for people who do not suffer from allergies. The kidneys help the urinary system, pollen is an effective adaptogen, stimulating the immune system and purifying the blood. However, due to its composition, which includes more than forty protein substances, birch pollen is a strong allergen. Particularly aggressive are protein compounds similar in structure to glycoproteins, they are the ones that provoke an allergic reaction in 90% of cases - itching, nasal discharge, lacrimation. In addition, an allergy to birch pollen can become cross-allergic and combine with a reaction to the flowering of alder and hazel (hazelnut), as well as cherries, apples, apricots and peaches.

There is a certain and well-studied system of cross-pollen of birch with the following plant species:

• Birch pollen and composite plants, flowers.
• Birch pollen and umbelliferous crops.
• Birch pollen and rose-colored plants.
• Treatment of pollen allergy.

The therapeutic strategy for any type of allergy, including hay fever, consists of the following steps:

1. Elimination, that is, maximum exclusion of contact with the provoking allergen.
2. Drug treatment of pollen allergy.
3. Prevention of hay fever recurrence.

Drug treatment of pollen allergy is the prescription of certain groups of drugs depending on the clinical picture of the disease. The following are drugs against pollinosis:

• Antihistamines.
• Glucocorticosteroids.
• Vasoconstrictors.
• Mast cell membrane stabilizers (cromoglycates).
• Anticholinergics or AChPs are anticholinergic drugs.

In addition, treatment of pollen allergy includes a gentle diet and adherence to certain rules of behavior, which primarily include minimizing contact with a flowering plant or tree. In some cases, special therapy - ASIT - is effective. Allergists recommend courses of allergen-specific immunotherapy, which significantly expands the boundaries of remission, sometimes up to five years, which helps the patient practically forget about the use of antihistamines and seasonal allergic reactions. However, ASIT (allergen-specific immunotherapy) is indicated only in cases with a specific allergy pathogen identified, which, unfortunately, is not common with hay fever.

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Tree pollen allergy

Hay fever to pollen secreted by trees begins in mid-spring, when alder and then birch blossom. Allergy to pollen from coniferous trees is rare, although spruce, fir and pine trees produce much more pollen than deciduous trees. This is due to the fact that the size of conifer pollen molecules is large, they are retained in the mucous membrane and rarely penetrate the bronchi, therefore, its immunogenicity is lower and the allergic reaction is much weaker. Of all tree species, birch and its family species are considered the most allergenic, followed by hazel (hazel) and ash. Considering that birch grows everywhere, in almost all countries of the world, except Australia and South Africa, allergy to pollen from birch trees affects millions of people every year.

List of trees whose pollen can trigger allergies:

• Betula is a birch tree that leads the list. The chemical composition of birch pollen includes about 40 albumin-like proteins, of which 6 are the most aggressive (immunogenic). The flowering season in various countries and territories begins at the end of March and ends at the beginning of June (in the northern regions).
• Alnus is an alder that belongs to the Betulaceae (birch) family. Alder begins to bloom earlier than birch, approximately from the end of February to mid-April. Alder produces slightly less pollen, but is also considered the main trigger for allergic reactions to tree pollen.
• Corylus is a hazel or nut tree, which is also a subspecies of the birch family, and its pollen causes severe allergies, including cross-allergies. Hazel blossoms early - from mid-February to mid-March, in some southern countries it can blossom and release pollen even in winter, for this it needs moisture and a temperature of 5 to 10 degrees Celsius.
• Fraxinus is an ash tree from the olive family. In addition to causing hay fever, ash pollen can also cause severe contact dermatitis. Ash blossoms in April and stops producing pollen in May.
• Salix – willow, willow, pussy willow, which grows everywhere where there are bodies of water. Allergy to pollen from trees of the willow family is less common than hay fever caused by birch, but the reaction to willow often ends in asthma attacks.
• Populus – poplar. Such a popular tree, which is usually blamed for almost all allergic troubles, is not actually the culprit of allergies. The fact is that during the flowering period, the fluff, as an adsorbent, absorbs pollen from flowering grasses and other allergy-provoking trees. Thus, poplar fluff itself is not allergenic, rather it can be considered a vehicle for the spread of plant and grass allergens.

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Allergy to plant pollen

Hay fever (allergy to plant pollen) is clearly associated with the seasonal flowering of certain trees, cereal crops, meadow grasses and weeds. To date, allergists have identified more than 750 plant species that provoke hay fever. Most often, allergies occur if a person comes into contact with pollen in the morning hours, since it is in the morning that most plants have a favorable time for pollination (pollen secretion). Also, a certain level of humidity and sun are considered to be conditions that help produce pollen. Allergy to plant pollen in rainy or dry periods is much less common for obvious reasons - there are no conditions for the maturation and production of pollen. In addition, seasonal allergies are clearly associated with the schedule and regional distribution of flowering. For allergy sufferers in many developed countries, plans and maps are being developed that indicate the periods of pollen production and a list of provoking plants.

The clinical picture that is typical for pollinosis is several forms of symptoms:

• Allergic rhinoconjunctivitis.
• Allergic tracheitis.
• Allergic laryngitis.
• Bronchial asthma.
• Bronchitis with asthmatic component.

Pollen allergy has been studied for quite some time, and the factors that provoke hay fever are systematized as follows:

1. Hay fever caused by trees and shrubs. Allergies can start in March and last until the end of May.
2. Allergy to cereals and grasses, reaction period – from mid-May to the end of June.
3. Hay fever associated with flowering weeds. Exacerbation begins in June and ends in late autumn.

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Allergy to flower pollen

Pollen from flowers, both wild and indoor, can cause an allergic reaction, however, most often it is a consequence of cross pollinosis. It should also be taken into account that an allergy to flower pollen can develop only if the flower belongs to wind-pollinated plants. Usually these are everyone's favorite meadow, wild flowers with large leaves and small, dull inflorescences, as well as plants of the fern family. All other plants with fragrant, large flowers are subject to "processing" by bees and other insects, so their pollen simply does not have time to be carried by the wind and provoke an allergy. Indoor flowers, as a rule, do not have pollen, since they reproduce in a different way, so all allergic reactions to them are more likely associated with the essential volatile compounds secreted by plants or milky juice, which causes contact dermatitis. Other cases where pollen allergy is noted are due to common antigenicity between the flower and a related plant, which is the main culprit of hay fever. Cross-reactivity (cross-allergy) is possible between cereal crops and the rose and lily families, between the pollen of wormwood, ragweed and the flowers of chamomile, daisy, aster or chrysanthemum. Doctors do not recommend that people with increased allergenic sensitivity plant or come into contact with the following types of flowers:

• Perennial flowers – chrysanthemum, aster, buttercups, hellebore, rudbeckia, coreopsis, zinnia.
• Annual plants – cornflower, geranium, primrose, stock, calendula, daisies, marigolds, lily of the valley.
• Climbing flowers – wisteria, clematis, morning glory.

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Allergy to weed pollen

Everyone knows that weeds, that is, weeds, grow everywhere. Obviously, there is no corner of the planet where one or another type of weed is not found, with the exception of perhaps mountainous areas, deserts and glaciers. Weeds are the most common type of carminative plants, their pollen is carried by the winds for many kilometers, so even city dwellers of huge megalopolises from time to time feel the effects of pollen plant allergens. It is believed that the most typical allergy to weed pollen is a reaction to ragweed. Food of the gods - this is how the plant from the Asteraceae family, imported from America, was named. Today, this plant is recognized throughout the world as quarantine, that is, subject to destruction: firstly, because it provokes allergies in millions of people, and secondly, because ragweed is capable of drying out the earth and creating a mini-desert around itself in literally two weeks. It is no coincidence that ragweed is called a living pump; it “drinks” moisture from the soil with such speed and power that even the most resilient plants around it die.

In addition, of all the weeds, it is Ambrosia that can cause the strongest allergies, including Quincke's edema and anaphylaxis. This is due to the composition of ragweed pollen, which includes a low-molecular protein - profilin, which overcomes all barriers of the mucous membranes of the nasopharynx. However, profilin (a protein compound) is also found in wormwood and quinoa, which are also common throughout almost the entire territory of Eurasia. The flowering of these herbs begins in August and lasts until the first cold weather in October. Recent studies by allergists have shown that over the past 10 years, the number of diagnosed pollinosis cases on dandelion, which is part of the Asteraceae family, has increased. Thus, dandelion can be considered a "relative" of ragweed, although it is not considered a weed. Less often, allergies to weed pollen are associated with the flowering of nettles or sorrel; almost all cases of hay fever to these plants are diagnosed as cross-allergic.

The list of allergy-provoking weeds, in addition to the infamous ragweed and wormwood, includes the following plants:

• Family of Chenopodiaceae:
  • Quinoa, goosefoot, beetroot, saltwort, desert spinach, dwarf saxaul, kochia.
• Asteraceae weeds:
  • Coltsfoot, tansy, chicory, succession, tarragon, elecampane, coltsfoot, dandelion, burdock.

It should be noted that allergy to weed pollen often overlaps with reactions to birch and alder pollen, as well as sunflower, wheat, oats, and rye. In addition, cross-allergy to food plant products is possible - tomatoes, apples, plums, pears, onions, melons, peaches, and rice. Considering the long flowering period of weeds (from early May to October), their widespread occurrence, pollinosis to weed pollen is considered one of the most severe allergic diseases, the only relative advantage of which is seasonality.

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Pollen allergy in children

The spring-summer period is not only the revival of nature and the increasingly hot sun, but also the season of typical diseases, which include pollen allergy in children. The peculiarity of childhood pollinosis is that at the first stage, its symptoms are similar to those of acute respiratory infections. Often, caring parents are sincerely convinced that their child continues to be ill as in winter, and complain about the excessive illness of the baby, his reduced immunity. Trying to cope with a runny nose on their own, mothers diligently drip and warm the child's nose, without getting the desired result. Neither hot milk with honey, nor infusions of medicinal herbs help, moreover, the symptoms can even worsen. Thus, pollen allergy in children is masked for quite a long time until the parents consult a doctor, where it turns out that the child does not suffer from a cold at all, but from seasonal pollinosis - one of the types of respiratory allergy.

Diagnosis of pollen allergy

Diagnosis of pollen allergy, as a rule, does not cause difficulties for allergists, which is due to the obvious cause-and-effect relationship - allergen - reaction and the seasonality of the disease. However, there is also a problem - identifying a specific allergen, since seasonal pollinosis has recently been characterized by cross-combinations (cross-allergy).

To determine the true allergy trigger, the following measures are taken:

• Collection of anamnesis, including family and household. This helps to more accurately determine the provoking factor, differentiate it (trees, cereals or grasses), and find out the possible hereditary etiology of the disease.
• Conducting allergy tests. Tests can be conducted in various ways - skin (scarification), intradermal (injection), nasal, etc. Tests help to specify the type of allergen with an accuracy of up to 100%.
• Laboratory blood tests to determine the level of eosinophils. If their number increases, this indicates that at least the body is predisposed to hay fever.
• An immunoenzyme test is a blood test to detect specific immune proteins (IgE), which are a marker of the presence of an allergen in the body.

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How to distinguish acute respiratory infections from signs of seasonal allergies?

Firstly, pollinosis is a typical seasonal disease, it cannot develop in the cold season, in winter, like colds. Pollen allergy is caused by pollen molecules, which, overcoming the barrier of the mucous membrane of the child's nasopharynx, penetrate the bronchopulmonary system and cause a severe allergic reaction. Accordingly, seasonal pollinosis is a disease that develops during the flowering period, that is, in spring and summer.

Secondly, acute respiratory infections usually pass in 10-14 days, unlike hay fever, which without proper treatment can last the entire flowering period of trees, plants or grasses.

Thirdly, mucus secreted from the nose during colds is thicker and more colored (greenish-yellow) than during allergies. Pollen allergy in children is manifested by the secretion of a liquid, transparent nasal secretion, the mucus almost never thickens.

Characteristic symptoms of hay fever in children:

• Hyperemia of the skin (face).
• Constant discharge of mucus from the nose, transparent in color and of rare consistency.
• An increase in body temperature is possible.
• Conjunctivitis, increased lacrimation, photophobia.
• Dry, frequent, superficial cough.
• Frequent sneezing.
• Skin rash, itching (dermatitis).
• Change in voice timbre, hoarseness.
• Shortness of breath, possible attacks of asthmatic cough.
• Irritability, capriciousness

Spring pollinosis in children can be provoked by blossoming birches, alder, ash, maple. In summer, the factor causing pollen allergy is almost all carminative herbs, flowers. In autumn - this is the well-known ragweed, wormwood, some types of cereal crops. Among the internal causes explaining the development of seasonal allergies in children, heredity is the leading one, followed by reduced immunity and hidden inflammatory processes in the nasal or bronchopulmonary system.

Parents should remember that seasonal pollinosis in a child requires timely diagnosis, treatment and adherence to certain nutritional rules. Provoking components are excluded from the menu:

• Limit protein foods (meat, fish).
• Spicy, smoked, pickled dishes.
• Offal (liver, lungs, heart).
• Chocolate.
• Citrus.
• Nuts.
• Strawberries, raspberries, currants, wild strawberries.
• Cherry, plum, peach, apricot.
• Oatmeal, wheat, barley porridge.

Of course, all of the listed products cannot be completely excluded from the child's diet; they must be limited and the body's reaction must be monitored. In addition, frequent washing, avoiding airing, avoiding synthetic detergents and synthetic clothing, walking only in places where there are no provoking plants, hardening and activating the immune system are simple measures that help prevent, stop or minimize the manifestations of seasonal allergies.

Statistics show that obvious signs of seasonal allergies most often appear in boys before puberty, while girls suffer from hay fever more often after 14-15 years. Seasonal allergies are diagnosed in 25% of all childhood allergies.

How to treat pollen allergy?

Treating seasonal pollinosis is quite difficult, since most often the patient seeks help already during the period when sensitization has occurred, that is, the body "acquaintance" with the allergen. Therefore, the first thing that allergists advise is to limit contact with provoking factors as much as possible - pollen of trees, grasses and cereals. Further, the question of how to treat pollen allergy can be answered by a long-term, carefully selected individual therapeutic strategy. As a rule, symptom relief is carried out with the following drugs, which are prescribed both in combination and as monotherapy, depending on the severity of the allergy:

• Medicines - antihistamines.
• Nasal vasoconstrictor drugs.
• Cromoglycates (sodium cromoglycate) are mast cell stabilizers.
• Glucocorticosteroids.

How to treat pollen allergy with antihistamines? The antihistamine group is a group of drugs that can effectively break the pathological connection between the antigen and substances produced by the immune system (histamine and others). Antihistamines are usually prescribed in tablet form, but during an exacerbation, intravenous administration of such drugs is indicated. Among the latest generation of drugs that do not cause drowsiness, addiction and other side effects, we can note Cetirizine, Cetrin, Zodak, Zestra, Claritin.

Treatment with vasoconstrictors helps to significantly alleviate nasal symptoms by affecting the adrenoreceptors of the nasal mucosa. The patient begins to breathe normally, and mucus secretion stops for a while. As a rule, vasoconstrictors are prescribed intranasally in the form of drops and sprays. In addition, for ophthalmological manifestations of allergy, which happens often, the use of eye drops containing sodium cromoglycate is indicated.

Treatment of pollen allergy with glucocorticosteroids is carried out strictly according to indications, with severe symptoms. As a rule, such therapy is indicated for people who already have a history of allergic diseases of other, non-pollen etiology.

One of the most effective methods in the treatment of allergies, including hay fever, is considered to be ASIT - allergen-specific immunotherapy. Today, ASIT is a method that helps to transfer seasonal allergies to a stage of stable remission lasting for many years. In addition, immunotherapy can prevent the transition of the initial stage of hay fever to a more severe form, accompanied by Quincke's edema and anaphylactic shock. The point of the method is to gradually "train" the body to react normally to pollen allergen with the help of micro-dosed administration of the antigen. Features of ASIT are as follows:

• Immunotherapy is not administered to children under seven years of age.
• ASIT is performed only during periods of long remission, usually in winter.
• ASIT is a long-term therapy that is carried out in several courses.
• Such hyposensitization helps to achieve a stable therapeutic effect and remission for at least 2 years.

Prevention of pollen allergies

Both in the fight against many diseases and in the treatment of hay fever, prevention of pollen allergy is the only reliable method that helps, if not to avoid the reaction and complex of symptoms, then to significantly reduce their severity. Preventive measures are a set of actions that are easy to perform, the only thing that is required of an allergy sufferer is to remember the rules and systematically adhere to them.

• Elimination of the provoking factor. Elimination means removing the allergen or avoiding contact with it. In terms of seasonal pollinosis, elimination involves changing the routine and time spent outdoors. Mornings, windy weather, groves, forests planted with allergy-provoking trees, cereal fields, meadows with meadow grasses are "taboo" for allergy sufferers. Walks are allowed in damp, rainy weather, in areas where there are no birches, ash, maple, alder and weeds.
• Conduct regular wet cleaning of the house and office premises, but ventilation should be done in the absence of the person suffering from allergies (the wind can carry pollen).
• When traveling, do not open the windows of your car or vehicle. It is advisable to avoid large crowds of people who may also carry pollen particles on their clothing.
• During the flowering period of trees, grasses, and cereals, it is necessary to regularly take a shower (not a bath), which will wash away the smallest particles of pollen.
• All hay fever sufferers should carefully read the information about cross-reactions to foods and, if possible, create a gentle menu.
• People suffering from hay fever should wear sunglasses throughout the summer season, which not only help to resist harmful ultraviolet radiation, but also partially protect the face (eyes) from contact with pollen.
• When going on a trip or a walk, you should have a first aid kit with you - an antihistamine, preferably in a soluble, nasal or inhalation form to quickly relieve a possible allergic attack.
• A good helper for people suffering from seasonal allergies is a special calendar of carminative flora flowering, which indicates the timing of pollination, territorial location and types of trees, plants and herbs.

A reliable and proven preventative measure for pollen allergy is preventive courses of ASIT (allergy-specific immunotherapy), which should be taken in advance, before the onset of the pollen season.