Allergic conjunctivitis is an inflammatory reaction of the conjunctiva to allergens, characterized by hyperemia and swelling of the eyelid mucosa, swelling and itching of the eyelids, the formation of follicles or papillae on the conjunctiva; sometimes allergic conjunctivitis is accompanied by damage to the cornea with visual impairment.
The reason for the development of allergic conjunctivitis can be: domestic, seasonal, environmental and industrial factors. Ambrose pollen and rim sunglasses, pet hair and pillow feathers, poplar fluff and pills, chitinous cover of small ticks living at the base of the eyelashes, and even expensive cosmetics can be allergens.
Workers in the woodworking, construction, chemical industry are at increased risk of developing allergic conjunctivitis; bakers, librarians, archives staff, livestock specialists, medical workers. Allergic chronic conjunctivitis, with periods of exacerbation, can occur on foods, especially with preservatives and other chemical additives.
The pathogenetic basis of allergic conjunctivitis is usually an immediate type of hypersensitivity reaction, which is caused by the release into the conjunctiva of biologically active mediators from activated mast cell granules, which play one of the most important roles in the pathogenesis of allergic conjunctivitis and are the source of the entire spectrum of allergy mediators.
An immediate type reaction is triggered by the interaction of an allergen with allergic antibodies belonging to class E immunoglobulins (IgE). Repeated allergen enters the conjunctiva occurs IgE -dependent activation of mast cells, causing release of inflammatory mediators:. Histamine, bradykinin, tryptase, leukotrienes, prostaglandins, and other mediators liberated cause the patient all the major symptoms of the allergic conjunctivitis (see clinical picture)
The clinical picture of allergic conjunctivitis may manifest an acute form with severe itching of the eyelids, burning under the eyelids, photophobia, tearing, severe conjunctival edema, and conjunctival hyperemia. Most often, it occurs chronically in the form of a mild burning sensation of the eyelids, a slight discharge, periodic itching of the eyelids. Often, numerous persistent complaints of unpleasant sensations are combined with an insignificant clinical picture, which is often confusing to doctors and makes it very difficult to diagnose allergic conjunctivitis.
Among the clinical forms of allergic conjunctivitis, there are spring, hay (pollinosis), scrofula ( phlyctenular ), large- capillary , drug, and conjunctivitis when wearing contact lenses. Spring conjunctivitis most often develops at the age of 10-20 years, accompanied by photophobia, itching, lacrimation, viscous filamentous discharge, the appearance of dense pink pale papillary growths on the upper conjunctiva of the upper eyelid.
The causative factor of hay conjunctivitis (pollinosis), as a rule, is plant pollen; this form of allergic conjunctivitis is characterized by itching, tearing, swelling and redness of the conjunctiva, the appearance of papillae on the mucous membrane of the upper eyelid, combined with rhinitis and catarrh of the upper respiratory tract. The development of medicinal conjunctivitis can provoke topical application of solutions and ointments of some drugs (atropine, scopolamine, pilocarpine, dikain, syntomycin, monomitsin), subject to individual intolerance against the background of prior sensitization to these preparations hormones.
Large-papillary conjunctivitis is a reaction to the long-term presence of a foreign body in the eye (lenses, stitches after ophthalmic operations), scrofulous is a consequence of pulmonary tuberculosis, bronchial and cervical lymph nodes (sensitization of eye tissues to M. tuberculosis antigens).
Diagnosis of allergic conjunctivitis in most cases is very difficult and includes the following measures:
(1) consultation with an ophthalmologist (including an allergist, immunologist, otorhinolaryngologist);
(2) laboratory tests (complete blood count and urinalysis, cytological, bacteriological and virological study of discharge from the eyes, RW and diagnosis of HIV infection, biochemical blood analysis;
(3) allergy and immunological study (skin tests with atopic allergens – prick-test, scarification test; determination of total serum and specific IgE);
(4) conjunctival provocation tests (carried out only by an allergist during the remission of allergic conjunctivitis).
In some cases, typical picture of the disease or its clear connection with the influence of an external allergenic factor leaves no doubt about the diagnosis.
Treatment of allergic conjunctivitis is based on three principles:
- mouth wounded “guilty allergen”,
- immunotherapy ,
- symptomatic drug therapy.
The complete elimination of the action of allergens, if possible, is the most effective and safest method of preventing an allergic reaction and therapeutic effects in an already developed clinical picture of the disease. If allergens are installed, (!) But they cannot be eliminated, then specific hyposensitizing immunotherapy is carried out ( histoglobulin injections are used , for a course of 6-10 injections).
Systemic use of antihistamines is indicated only for severe allergic conjunctivitis as part of complex therapy for three to six days. In subacute and chronic conjunctivitis, and also for prophylaxis in the eye drops used as stabilizers cromoglycates conjunctival mast cells (for example, 2% – nye kromogeksal eyedrops or 0.1% – s lodoxamide ). Corticosteroids (prednisone), vasoconstrictor and non-steroidal anti-inflammatory drugs, artificial tears can be prescribed.