Bacterial infections of the conjunctiva are caused by various pathogens and are, with rare exceptions (S.aureus, Proteus, Moraxella), mild illnesses. The quick effect of the therapy is apparently due to the fact that even with topical application, a high concentration of antibiotic is created on the surface of the eye.

Bactericidal antibiotics are preferred for use (especially in patients with immunodeficiency conditions). In adult patients it is recommended to use drugs in the form of eye drops during the day, as the ointments reduce visual acuity. Before going to bed, it is better to use antibiotics on an ointment basis, as this increases the time of contact of the drug with the surface of the eye.

The conjunctiva is very resistant to infections. The lacrimal fluid, which has antibacterial activity due to the content of immunoglobulins, complement components, lactoferrin, lysozyme and beta-lysine, in combination with the function of the eyelids, mechanically reduces the number of bacteria on the surface of the eye. Injury or other eye damage causes the release of macrophages and polymorphic nuclear neutrophils from the vessels of the conjunctiva into the tear fluid. In combination with the relatively low temperature of the surface of the eye and the adhesive properties of the mucosa, acute infection is limited.

The edges of the eyelids and, to a lesser extent, the surface of the conjunctiva can be colonized by various microorganisms. The microflora includes staphylococci (more than 60%, mainly Staphylococcus epidermidis), diphtheroids, propionibacteria. Local risk factors include traumatic injuries, the presence of foreign bodies, certain skin diseases (erythema multiforme) and infections of the lacrimal ducts.

Keratitis is one of the complications of conjunctivitis with serious consequences that can lead to vision loss. At the same time, risk factors are considered to be prolonged closure of the eyelids, wearing of soft contact lenses and traumatic damage to the corneal epithelium. Because of the risk of keratitis, topical prophylactic use of antibiotics is of great importance.

Viral conjunctivitis caused by adenoviruses is the most common form of conjunctivitis. It is necessary to establish the etiology of conjunctivitis in each case (Table 1), in order to solve the problem of the use of antibiotics. Doctors usually do not have problems detecting the presence of conjunctival injection and purulent discharge, however, some problems can arise with the differentiation of lymphoid follicles and papillae. Associated with a viral infection, the lymphoid follicles are imposing formations with a diameter of 1 to 2 mm and located mainly on the conjunctiva of the lower eyelid and in the lower conjunctival fornix. The follicles can also be observed with a chlamydia conjunctivitis (larger), toxic and Moraxella. Unlike the follicles, the taste buds look like multiple microscopic elevations, are not specific, and are more characteristic of a bacterial infection.

With the fulminant form of bacterial conjunctivitis, clinical symptoms are more pronounced and progress more rapidly than in the acute form. In the etiology of fulminant bacterial conjunctivitis, the main role is played by Neisseria gonorrhoeae. The disease is characterized by edema of the conjunctiva and eyelids, a large conjunctival injection and abundant purulent discharge. In typical cases, the incubation period is 1 to 3 days. With gonococcal conjunctivitis, adults usually have a urogenital gonococcal infection, while newborn infection occurs when passing through the birth canal.

With fulminant bacterial conjunctivitis, immediate initiation of systemic antibiotic therapy is necessary due to the high risk of corneal damage. In adult patients, the drug of choice is ceftriaxone (1 g, once, IM). At the same time, in newborns, in addition to intravenous or intramuscular administration of ceftriaxone (25-50 mg / kg), it is necessary to rinse the eyes with saline and, due to the possibility of chlamydial co-infection, to prescribe active drugs against Chlamydia trachomatis.

The use of a 1% silver nitrate (AgNO3) solution is a standard method for the prevention of gonococcal conjunctivitis, physical eye wash. a solution immediately after instillation of a silver nitrate solution is not recommended. In addition, for prophylactic purposes, drops with erythromycin or a 2.5% solution of povidone iodine can be used. However, it should be noted that with the equivalent effectiveness of the above three drugs against Neisseria gonorrhoeae, povidone iodine is most active against Chlamydia trachomatis.

In addition to a rapid increase in clinical symptoms, acute bacterial conjunctivitis is characterized by mucopurulent discharge and a predominant lesion of the bulbar conjunctiva. The clinical symptoms usually disappear after 10 to 14 days, sometimes even without specific treatment. However, with conjunctivitis caused by Staphylococcus aureus and Moraxella catarrhalis, the process can become chronic. In addition, staphylococci have the ability to colonize the edges of the eyelids and cause chronic blepharitis. The main role in the etiology of acute bacterial conjunctivitis is played by gram (+) cocci (Table 2), however, in the presence of anterior conjunctival lesions, the role of gram (-) microorganisms increases.

Pneumococcal conjunctivitis is generally prone to self-healing and is accompanied by subconjunctival hemorrhages, as is conjunctivitis caused by Haemophilus influenzae (biological group aegyptius) , endemic to tropical and subtropical regions. Conjunctivitis caused by Streptococcus pyogenes is characterized by the formation of pseudomembranes on the bulbar conjunctiva. Pseudomonas conjunctivitis is rare, but its danger lies in the high risk of infection and perforation of the cornea, especially with prolonged use of soft contact lenses and with traumatic lesions of the cornea.

The main treatment for acute bacterial conjunctivitis is the local use of antibiotics. The drops are usually applied at intervals of 1 to 4 hours, ointments - 4 times a day. Treatment should continue until the clinical symptoms have completely disappeared, usually 10 to 14 days. Currently, the aminoglycosides, which have been used for many years for the local treatment of bacterial conjunctivitis (with the exception of streptococci and pneumococci), have been replaced by fluoroquinolones. However, an increase in resistance to fluoroquinolones has been noted and, therefore, their use in ophthalmic practice should only be limited to severe destructive bacterial lesions. Currently, the most justified is the use of a combination of polymyxin-B and trimethoprim in the form of drops and a combination of polymyxin-B and bacitracin in the form of ophthalmic ointment. Systemic antimicrobial therapy is rarely used in acute uncomplicated bacterial conjunctivitis, with the exception of hemophilic conjunctivitis in children and infection in all age groups of the Haemophilus influenzae aegiptius, which is often accompanied by the development of serious complications.

The most common causative agent of chronic bacterial conjunctivitis is S. aureus. The role of S.epidermidis, a representative of the normal microflora of the surface of the eye, is much weaker. Chronic staphylococcal conjunctivitis, often accompanied by blepharitis, is characterized by a slow response to local antibiotic therapy. Bacitracin ointment, after a short period of more frequent use, can be used once a day at bedtime for several months until clinical recovery is achieved. The 1% vancomycin solution obtained by diluting the parenteral form can be used as eye drops for the treatment of infections caused by strains resistant to oxacillin / methicillin (MRSA).