Allergic conjunctivitis

Allergic conjunctivitis is an inflammatory reaction of the conjunctiva to the effects of allergens. Allergic conjunctivitis occupies an important place in the group of diseases united by the general name "red eye syndrome", it affects about 15% of the population.

Eyes are often exposed to various allergens. Increased sensitivity often manifests itself as an inflammatory reaction of the conjunctiva (allergic conjunctivitis), but any part of the eye can be affected, and then allergic dermatitis, conjunctivitis, keratitis, iritis, iridocyclitis, and optic neuritis develop.

Allergic reaction in the eyes can manifest itself in many systemic immunological diseases. Allergic reaction plays an important role in the clinical picture of infectious eye lesions. Allergic conjunctivitis is often combined with such systemic allergic diseases as bronchial asthma, allergic rhinitis, atopic dermatitis.

Allergic reactions are divided into immediate (developing within half an hour from the moment of exposure to the allergen) and delayed (developing 24-48 hours or later after exposure). This division of allergic reactions has practical significance in providing medical assistance.

In some cases, a typical picture of the disease or its clear connection with the impact of an external allergen factor do not raise doubts about the diagnosis. In most cases, diagnostics is associated with great difficulties and requires the use of specific allergological research methods. To establish a correct diagnosis, it is necessary to establish an allergological anamnesis - to find out about hereditary allergic burden, the features of the course of diseases that can cause an allergic reaction, the periodicity and seasonality of exacerbations, the presence of allergic reactions, in addition to eye ones.

Specially conducted tests have great diagnostic value. For example, skin allergy tests used in ophthalmological practice are low-traumatic and at the same time quite reliable.

Laboratory allergy diagnostics is highly specific and possible in the acute period of the disease without fear of causing harm to the patient.

The detection of eosinophils in conjunctival scrapings is of great diagnostic importance. Basic principles of therapy:

• elimination of the allergen, if possible; this is the most effective and safe method of preventing and treating allergic conjunctivitis;
• medicinal symptomatic therapy (local, with the use of eye medications, general - antihistamines taken orally for severe lesions) occupies a major place in the treatment of allergic conjunctivitis;
• Specific immunotherapy is carried out in medical institutions if drug therapy is not effective enough and it is impossible to exclude the “culprit” allergen.

For anti-allergic therapy, two groups of eye drops are used:

• inhibiting mast cell degranulation: cromops - 2% lecrolin solution, 2% lecrolin solution without preservative, 4% kuzikroma solution and 0.1% lodoxamide solution (alomid);
• antihistamines: antazoline and tetryzoline (spereallerg) and antazoline and naphazoline (allergoftal). Additional drugs: 0.1% dexamethasone solution (dexanos, maxidex, oftan-dexamethasone) and 1% and 2.5% hydrocortisone solution - POS, as well as non-steroidal anti-inflammatory drugs - 1% diclofenac solution (diclor, naklor).

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Symptoms of allergic conjunctivitis

The most common clinical forms of allergic conjunctivitis are:

• Phlyctecular (tuberculous-allergic conjunctivitis);
• Pollinosis conjunctivitis, drug-induced conjunctivitis;
• Pollinosis conjunctivitis;
• Spring catarrh;
• Hay fever;
• Hay fever.

Phlyctecular (scrofulous) allergic conjunctivitis

Phlyctecular (scrofulous) allergic conjunctivitis is a tuberculous-allergic eye disease. On the connective tissue or on the limbus, individual or multiple inflammatory nodules of a yellowish-pink color appear, which to this day have retained the incorrect name of "phlyctena" - bubbles. The nodule (phlyctena) consists of cellular elements, mainly lymphoid cells with an admixture of cells of the elyteloid and plasmatic types, sometimes giant ones.

The appearance of nodules on the conjunctiva, especially on the limbus, is accompanied by severe photophobia, lacrimation and blepharism. Nodules can also develop on the cornea. Conjunctival infiltrate (phlyctena) most often resolves without a trace, but sometimes disintegrates with the formation of an ulcer, which, healing, is replaced by connective tissue.

Scrofulous conjunctivitis is observed mainly in children and young people suffering from tuberculosis of the cervical and bronchial lymph nodes or lungs. A phlyctena is a nodule similar in structure to a tubercle, never contains tuberculosis mycobacteria and does not undergo caseous decay. Therefore, scrofulous conjunctivitis is considered a specific reaction of the allergic mucous membrane of the eye to a new influx of tuberculosis mycobacteria decay products. The appearance of phlyctena in children should direct the doctor's attention to a thorough examination of the child.

A simple and fairly complete classification by A. B. Katznelson (1968) includes the following allergic conjunctivitis:

1. atopic acute and chronic;
2. contact allergic (dermatoconjunctivitis);
3. microbiological allergic;
4. spring catarrh.

Pollen, epidermal, medicinal, less often food and other allergens are most often to blame for the development of the first form. Acute atopic conjunctivitis is most pronounced, with pronounced objective symptoms. Reflecting the immediate reaction, from: characterized by patient complaints of unbearable burning, cutting pain, photophobia, lacrimation and objectively very rapid increase in conjunctival hyperemia and its edema, often vitreous and massive, up to chemosis, abundant serous discharge, hypertrophy of conjunctival papillae. The eyelids swell and redden, but the regional lymph nodes are intact. Eosinophils are found in the discharge and scrapings of the conjunctiva. Superficial punctate keratitis is occasionally observed. Instillation of adrenaline, saporin or another vasoconstrictor against this background dramatically changes the picture: while the medicine is effective, the conjunctiva looks healthy. Slower, but stable improvement, and soon recovery are provided by antihistamines applied locally and internally. Corticosteroids, as a rule, are not indicated.

Chronic atopic conjunctivitis

Chronic atopic conjunctivitis has a completely different course, characterized by abundant complaints of patients and scanty clinical data. Patients insistently demand relief from the constant sensation of "clogged" eyes, burning, lacrimation, photophobia, and the doctor at best finds only some pallor of the conjunctiva, sometimes slight hyperplasia of the papillae and compaction of the lower transitional fold, and more often sees an externally unchanged conjunctiva and can assess the complaints as neurotic (A. B. Katsnelson). Diagnosis is often difficult not only due to the paucity of symptoms, but also because the allergen is well "masked", and until it is found and eliminated, treatment brings only temporary improvement. The atopic nature of this disease can be assumed on the basis of a positive allergic anamnesis of the patient and his relatives, which is confirmed by eosinophilia in the study of a smear or scraping. When searching for an allergen, which is complicated by inconclusive skin tests, the patient's own observation is of great importance. While the search is underway, relief can be provided by periodically replacing one another with drops of diphenhydramine, 1% antipyrine solution, zinc sulfate with adrenaline, etc. For such patients, usually elderly people, it is especially important to warm up the drops before instillation, prescribe weak sedatives (bromine, valerian, etc.), emphasize the attentive and tactful attitude of the medical staff, instill in patients at each visit to the doctor the idea of the complete safety of the disease for vision and general health, its curability under certain conditions.

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Contact allergic conjunctivitis and dermatoconjunctivitis

Contact allergic conjunctivitis and dermatoconjunctivitis are identical in pathogenesis to contact dermatitis and eczemas. They most often arise as a result of the effect of exogenous allergens on the conjunctiva or on the conjunctiva and skin of the eyelids, and are much less often a reflection of endogenous allergic influences. The set of antigens causing this form of conjunctivitis is as extensive as in dermatitis of the eyelids, but the first place among irritants is undoubtedly occupied by medications used locally in the eye area; they are followed by chemicals, cosmetics, plant pollen, household and industrial dust, allergens of animal origin, etc. Of lesser importance are food and other allergens entering the conjunctiva with blood and lymph. The disease develops in a slow manner, beginning after repeated, often multiple contacts with the allergen.

The clinical picture of the disease is quite typical: with complaints of severe pain, burning, photophobia, inability to open the eyes, intense hyperemia and swelling of the conjunctiva of the eyelids and the eyeball, hyperplasia of the papillae, abundant serous-purulent discharge ("pours from the eyes"), which contains many eosinophils and epithelial cells that have undergone mucous degeneration, are noted. The eyelids swell. Signs of dermatitis of the eyelids are not uncommon. These symptoms reach a maximum and can last a long time with continued exposure to an allergen, the detection of which can be helped by skin tests.

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Microbiological allergic conjunctivitis

Microbiological allergic conjunctivitis is called so, and not microbial, because it can be caused not only by microbes, but also by viruses, fungi, other microorganisms, and also helminth allergens. However, the most common cause of its development is staphylococcal exotoxins, produced mainly by saprophytic strains of the microbe.

The allergic process of microbiological genesis differs from bacterial, viral and other inflammations of the conjunctiva by the absence of a pathogen in the conjunctival sac and the peculiarities of clinical manifestations. Being a delayed-type allergic reaction, such conjunctivitis, as a rule, proceeds chronically, resembling chronic atopic conjunctivitis with abundant complaints of patients and moderate objective data. The leading symptoms are: proliferation of papillae of the palpebral conjunctiva, its hyperemia, which intensifies with work and any irritations. The process is often combined with simple (dry) or scaly blepharitis. In scanty discharge there may be eosinophils and altered cells of the conjunctival epithelium. Skin tests with disease-causing microbial allergens are desirable in these cases, and in the search for an irritant, a test with a staphylococcal antigen is primarily indicated. Treatment with corticosteroids (locally and internally), vasoconstrictors, astringents, until the allergen is eliminated, gives only a transient improvement. Sanitation of the body is carried out by appropriate antimicrobial, antiviral and other therapy, combined if necessary with surgical and other methods of eliminating foci of chronic infection.

True allergic conjunctivitis is not characterized by the formation of conjunctival follicles. Their appearance indicates not so much an allergenic as a toxic effect of the damaging agent. Such are, for example, atropine and eserine conjunctivitis (catarrhs), molluscum conjunctivitis - a viral disease, but resolving until the molluscum, masquerading somewhere on the edge of the eyelid, is removed.

Considering the great similarity of etiology and pathogenesis with uveal and other allergic processes in the eye, it is considered possible to designate this form by the more familiar to ophthalmologists term “infectious-allergic conjunctivitis”.

As an exception to the general rule, follicles are the only symptom of folliculosis, reflecting the reaction of the conjunctiva, usually in children, to exo- and endogenous irritations. The reasons for the occurrence of this chronic condition of the conjunctiva may be anemia, helminthic invasions, diseases of the nasopharynx, gyno- and avitaminosis, uncorrected refractive errors, unfavorable environmental influences. Children with folliculosis need examination and treatment by a pediatrician or other specialists. The now rare follicular conjunctivitis is infectious and allergic in nature.

A. B. Katsnelson classifies phlyctenular keratoconjunctivitis as a microbiological allergic process, considering it a “classic clinical model of late-type microbial allergy.”

A clinical classification of drug allergy of the conjunctiva, as well as other parts of the visual organ, based on the identification of the leading symptom of the pathology, was proposed by Yu. F. Maychuk (1983).

A special form of allergic conjunctivitis, significantly different from the above processes, is spring catarrh. The disease is unusual in that it is common in more southern latitudes, affects mainly males, more often during childhood and puberty, and manifests itself with symptoms that are not present in any other eye pathology. Despite intensive research, none of the features of the disease have yet received a convincing explanation. Eye disease begins in boys at 4-10 years of age and can continue until adulthood, sometimes ending only by the age of 25. The average duration of suffering is 6-8 years. In chronic course, the process is cyclical: exacerbations occurring in spring and summer are replaced by remissions in the cool season, although year-round activity of the disease is not excluded. Both eyes are affected. Patients are bothered by a sensation of a foreign body, photophobia, lacrimation, deterioration of vision, but itching of the eyelids is especially painful. Objectively, the conjunctiva or limbus or both together change, which allows us to distinguish between palpebral or tarsal, limbal or bulbar and mixed forms of catarrh. The first form is characterized by a slight ptosis, massive, flat, cobblestone-like, polygonal, milky-pink or bluish-milky papillary growths on the conjunctiva of the cartilage of the upper eyelid, which persist for years, but, disappearing, do not leave a scar.

In limbal vernal catarrh, moderate pericorneal injectia, dense glassy, yellowish-gray or pinkish-gray growths of the conjunctiva along the upper limbus, sometimes waxy-yellow nodes, and in severe cases, a dense shaft of newly formed tissue above the limbus with an uneven surface on which white dots are visible (Trantas spots) are noted. The mixed form combines damage to the conjunctiva of the upper cartilage and limbus. In all forms, there is little discharge, it is viscous, stretches into threads, eosinophils are often found in smears and scrapings.

The allergic genesis of the disease is beyond doubt, but the allergen is unclear. Most researchers in one way or another associate spring catarrh with ultraviolet radiation, hereditary predisposition, endocrine influences; in 43.4% of examined patients with spring catarrh, Yu. F. Maychuk (1983) found sensitization to non-bacterial and bacterial allergens.

Treatment of allergic conjunctivitis

Treatment is mainly aimed at desensitization and strengthening of the child's body; vitamins, a carbohydrate-restricted diet and the following medications are recommended:

• 2% solution of sodium cromoglycate or alamide 4-6 times a day;
• 0.1% dexamethasone solution in drops 3-4 times a day;
• for local treatment, instillation of streptomycin in a dilution of 25,000-50,000 IU in 1 ml of solution is prescribed 2-3 times a day;
• 3% calcium chloride solution 2-3 times a day; 1% cortisone 2-3 times a day.

In severe persistent cases of the disease, a general course of treatment should be carried out with streptomycin, PAS and phthivazid in doses prescribed by phthisiatricians, and other anti-tuberculosis drugs.

In case of severe blepharospasm, lacrimation, photophobia, pericorneal injection, use a 0.1% solution of atropine sulfate 2-3 times a day. It is useful to perform daily iontophoresis with calcium chloride.

Hay conjunctivitis is an allergic disease caused by an allergen (usually pollen from cereals and some other plants) getting on the mucous membrane of the eye, nose, and upper respiratory tract. It begins acutely, with severe photophobia and lacrimation. The conjunctiva is very hyperemic, swollen, and its papillae are hypertrophied. Severe itching and burning are a concern. The discharge is watery. The disease is accompanied by acute rhinitis, catarrh of the upper respiratory tract, and sometimes high temperature. Hay conjunctivitis occurs in early childhood or during puberty. Symptoms of conjunctivitis recur annually, but weaken with age and may disappear completely in old age.

For hay conjunctivitis, desensitizing therapy is recommended, 2% sodium cromoglycate solution or "Alomid" 4-6 times a day. Cortisone is prescribed locally, 1-2 drops 3-4 times a day, 5% calcium chloride solution 1 tbsp. 3 times a day during meals, intravenously 10% calcium chloride solution 5-10 ml daily.

The development of hay conjunctivitis can sometimes be prevented by carrying out the above treatment long before the beginning of the flowering of cereals. If the treatment is ineffective, then it is necessary to move to an area where there are no cereals that cause the disease.

How to prevent allergic conjunctivitis?

To prevent the disease, it is necessary to take certain measures.

It is necessary to eliminate the causative factors. It is important to reduce, and if possible, eliminate contact with such risk factors for the development of allergies as house dust, cockroaches, pets, dry fish food, household chemicals, cosmetics. It should be remembered that in patients suffering from allergies, eye drops and ointments (especially antibiotics and antiviral agents) can cause not only allergic conjunctivitis, but also a general reaction in the form of urticaria and dermatitis.

If a person finds himself in conditions where it is impossible to exclude contact with factors that cause allergic conjunctivitis, to which he is sensitive, he should start instilling lecromin or alomid, 1 drop 1-2 times a day 2 weeks before contact.

1. If the patient has already found himself in such conditions, Allergoftal or Persalerg are instilled, which provide an immediate effect that lasts for 12 hours.
2. In case of frequent relapses, specific immunotherapy is carried out during the period of conjunctivitis remission.