LECTURE No. 12. Trachoma

Trachoma is a chronic infectious disease of the eyes. The causative agent of the infection is the microorganism chlamydia, which causes damage to the conjunctiva and cornea, resulting in scarring, destruction of the cartilage of the eyelids and complete blindness. The disease has been known since ancient times; trachoma has long been found among the populations of Africa and Asia. The appearance of trachoma in Europe is associated with the campaign of Napoleon Bonaparte’s troops in Egypt in 1798. Currently, in the countries of Africa, Southeast Asia, and South America, there are more than 400 million patients with trachoma, including 200 million cases of complete blindness caused by trachoma . There is no trachoma in Russia, only imported cases occur.

Etiology and epidemiology. The causative agent of trachoma was discovered in 1907, it is found in the cells of the epithelium of the conjunctiva and cornea, and in its properties and intracellular development cycle is similar to other chlamydia.

Trachoma is an anthroponotic disease (transmitted only from person to person) with an epidemic spread. The living conditions of the population and the level of its sanitary culture play an important role in the spread of trachoma. The transfer of the infectious agent is carried out by direct and indirect means (through hands, clothes, towels). The main sources of infection in the foci of trachoma are patients with active forms of the disease. An essential role in the transmission of the infection also belongs to the carriers of the infectious agent, persons with its unusual localization (for example, in the lacrimal ducts) and an atypical course of the process. The role of flies in the mechanical transfer of the pathogen is not excluded.

Susceptibility to trachoma is universal and high. Immunity after the transferred disease is absent. Trachoma is widespread in tropical and subtropical countries. In Russia, this infection has been eliminated.

Pathological anatomy. In the initial period of trachoma, diffuse infiltration of neutrophilic leukocytes and histiocytes is determined in the conjunctiva. Starting from the tenth to twelfth day, lymphocytic and plasma cell infiltration develops. In addition to diffuse infiltration, trachoma is characterized by the formation of follicles, which at first are focal accumulations of lymphocytes. The trachomatous process is marked by early onset dystrophic changes and necrosis of the tissues of the conjunctiva, primarily in the area of ​​the follicles. The stroma of the follicles undergoes sclerosis and hyalinosis, but their resorption without scar formation is possible. A fibrous tissue develops around the follicles, forming a capsule, in which cell infiltrates and the infectious agent can remain "immured" for many years. In patients with a severe course of the disease, diffuse-infiltrative processes in the conjunctiva and edema predominate, there is a thickening of the conjunctiva with an increase in the size of the follicles and their noticeable protrusion of the papillary form of trachoma. In the cornea, there is diffuse inflammation of varying intensity with the penetration of newly formed vessels and infiltration into the region of the upper limbus and the formation of trachomatous pannus (clouding of the surface layers of the cornea). In severe cases, follicles appear in the stroma (own substance) of the cornea. In the lacrimal organs there is inflammation with lymphoid plasma infiltration and scarring. Severe cases are characterized by the spread of infiltration into the deep layers of the cartilage of the eyelids. In the meibomian glands, the development of cysts, vacuolization, fatty degeneration, hyalinosis, cartilage amyloidosis are observed.

Clinical picture. The incubation period is seven to fourteen days. The onset of the disease is acute, but in many patients it develops gradually, and the course of the infection is chronic. Both eyes are usually affected. The onset of the disease is possible without any sensations. Sometimes there is a slight mucopurulent discharge, a sensation of a foreign body and a burning sensation in the eyes. With the acute onset of the disease, symptoms of acute conjunctivitis are observed (redness of the skin of the eyelids, photophobia, copious mucopurulent discharge, the conjunctiva is swollen and hyperemic).

There are four stages during the trachomatous process:

1) development of follicular reaction, lymphoid subconjunctival infiltration, limbitis (inflammation of the limbus) and pannus of the cornea;

2) the appearance of scars replacing follicles;

3) the predominance of scarring of the conjunctiva and cornea;

4) ending scarring, covering the conjunctiva, cornea, cartilage of the eyelids.

Depending on the predominance of certain pathological elements in the active period (first-third stages) of trachoma, four forms of the disease are distinguished:

1) follicular, in which predominantly follicles are observed;

2) papillary with a predominance of papillary growths;

3) mixed, when both follicles and papillary growths are found;

4) infiltrative, characterized by predominant infiltration of the conjunctiva and cartilage of the eyelids. The clinical picture of trachoma when infected in early childhood is similar to neonatal blenorrhea. Repeated exacerbations in these patients cause the development of corneal cicatricial changes characteristic of trachoma.

The most severe complication of trachoma is a trachomatous corneal ulcer, which is promoted by a secondary bacterial infection. In addition, complications of trachoma include acute and chronic conjunctivitis, progressed due to the addition of a bacterial or viral infection. In trachoma, diseases of the lacrimal ducts are often observed, caused by the causative agent of trachoma in combination with a secondary infection.

The consequences of trachoma are due to the process of scarring, which leads to the appearance of adhesions between the conjunctiva of the eyelid and the eyeball. In this case, the conjunctival arches are shortened or disappear altogether. Changes in the cartilage of the upper eyelid in trachoma lead to inversion of the eyelid, abnormal growth of eyelashes. As a consequence of trachoma, drooping of the upper eyelid (ptosis) develops, giving the face a peculiar sleepy expression. As a result of cicatricial changes in the lacrimal gland, lacrimation decreases, drying of the conjunctiva and cornea xerosis occurs. Pronounced scarring of the conjunctiva, combined with trichiasis (improper growth of eyelashes) and inversion of the eyelids, leads to reduced vision, and scarring and clouding of the cornea to partial or complete loss of vision.

Diagnostics. The diagnosis of trachoma is established when at least two of the four cardinal signs of the disease are detected, such as follicles on the conjunctiva of the upper eyelid, follicles in the region of the upper limb or their consequences (fossae), typical conjunctival scars, pannus, more pronounced in the upper limbus. In epidemic foci of trachoma, one of these symptoms is sufficient for the diagnosis. The diagnosis is confirmed by a cytological method (detection of cytoplasmic inclusions of the causative agent of Provachek Halberstedter bodies in epithelial cells), detection of chlamydia antigens by immunofluorescent methods in epithelial cells of scrapings from the conjunctiva, isolation of chlamydia from the conjunctiva by cultivation in the gall sac of chicken embryos or in tissue culture, determination of specific antibodies in serum blood.

The predominantly sluggish course of inflammation of the mucous membrane, accompanied by diffuse infiltration of the submucosal tissue, the presence of papillae, follicles and whitish scars, swelling in the limbus, infiltration and neoplasm of vessels in the cornea, going mainly from top to bottom (pannus), indicate primarily trachomatous keratoconjunctivitis (trachoma ).

Under the conditions of a mass examination in trachomatous foci in the presence of subtle and atypical follicles, minor and uncharacteristic changes in the cornea, negative laboratory results, a diagnosis is made such as suspected trachoma. With mild hyperemia of the conjunctiva of the eyelids and its slight infiltration, the absence of follicles and questionable changes in the cornea, but if there are inclusions in the scraping from the conjunctiva, they speak of pretrachoma.

If patients periodically complain about the sensation of a foreign body, heat in the eyes, if discharge is observed, the conjunctiva is hyperemic and sharply infiltrated, and papillae (papillary form) and follicles (follicular form) are visible around the vessels, the number and size of which are varied, then this is trachoma of the first stage , or the initial progressive phase of the disease.

All changes, as a rule, develop first in the region of the lower transitional fold, since there is more adenoid tissue, but they are more easily detected on the conjunctiva of the upper eyelid, in the region of the upper transitional fold. First of all, follicles are found in the semilunar fold and on the lacrimal caruncle. It is possible to have both follicles (in children) and papillae (mixed form) on the infiltrated conjunctiva.

If inflammation and infiltration of the conjunctiva and adenoid tissue are combined with degeneration, disintegration of follicles and their replacement with connective tissue (scarring), which is detected only using a combined examination method or in the light of a slit lamp (dots and white stripes in transitional folds and on the conjunctiva of the cartilage of the upper eyelid ), and a not very pronounced ptosis is visible, which developed as a result of the spread of infiltration and scarring in the area of ​​the levator tendon and Müller muscle, that is, there is reason to characterize this process as a pronounced regressive (second) stage of trachoma.

The third stage of the disease is characterized by a slight inflammation in the form of a gentle infiltration, the presence of single follicles and a large number of white scars in the conjunctiva.

The fourth stage of trachoma, or the stage of clinical recovery, is characterized by the presence of cicatricial changes in the mucous membrane of the eyelids and eyes without signs of inflammation.

Already in the first stage of trachoma in the cornea, manifestations of pannus limbitis can be detected. The limbus is edematous and cloudy, its vessels are full-blooded and dilated, small gray and gelatinous follicles are observed around the vessels.

In the second and third stages of the disease, superficial infiltrates are visible in the cornea on the border with the upper limbus, which, merging, form a diffuse opacification of the cornea. These opacities are penetrated by superficial conjunctival vessels, anastomosing with each other.

Depending on the number of conjunctival vessels that have sprouted into the cornea, several types of pannus can be distinguished: micropannus (thin) vessels are few, corneal infiltration is gentle; vascular a large number of vessels grow into the clouded part of the cornea; fleshy (sarcoidosis) significant infiltration and vascularization of the cornea.

Complications. Frequent consequences of trachoma are inversion of the eyelids and abnormal growth of eyelashes trichiasis, as a result of which the cornea and conjunctiva are mechanically irritated and injured. Possible posterior simblefaron fusion of the conjunctiva of the eyelids with the conjunctiva of the eyeball.

A severe consequence of trachoma, which develops as a result of severe scarring of the conjunctiva and leads to the death of the glandular apparatus, the closure of the ducts of the lacrimal glands and their death, is xerosis, the drying of the mucous membrane and cornea. These changes can be detected in the third stage of trachoma.

The fourth stage of trachoma is divided into four groups depending on the degree of visual acuity reduction:

1) zero group without visual impairment;

2) the first group decreased vision to 0,8;

3) the second group decreased vision to 0,4;

4) the third group decreased vision below 0,4.

Treatment and prevention. Topically apply 1% ointments or solutions of tetracycline, erythromycin, oletethrin, 10% solutions of sodium sulfapyridazine, 5% ointments or 3050% solutions of etazol 36 times a day. If necessary, one to two weeks after the start of treatment, follicle expression is performed. In cases of severe trachoma, the use of tetracycline, oletethrin, etazol, sulfapyridazine is recommended, and vitamin therapy and the elimination of allergic manifestations are also indicated. In complex therapy, interferon and interferon inducers, immunomodulators are used. At the stage of outcomes and consequences, surgical treatment (corrective and plastic) is carried out. Timely and systematic use of antibiotics and sulfonamides makes it possible to achieve a cure and prevent complications.

Drug therapy is combined with mechanical (squeezing (expression) of follicles), which contributes to a more active effect of antibiotics on the flora and gentle scarring. Expression is performed once every two weeks under local anesthesia, after which active drug therapy continues again.

Patients who have tender scars are considered cured. For six months they must instill a 30% solution of albucid, and then a commission of ophthalmologists decides on further anti-relapse treatment and its duration.

Prevention is reduced to the timely detection of patients, their clinical examination and regular treatment.

Author: Shilnikov L.V.

<< Back: Clinical features and principles of treatment of some conjunctivitis and conjunctival tumors (Acute epidemic conjunctivitis (Koch-Wicks conjunctivitis). Pneumococcal conjunctivitis. Blenorrheal conjunctivitis. Diphtheria conjunctivitis. Treatment of bacterial conjunctivitis. Adenopharyngoconjunctival fever (AFCL). Epidemic follicular keratoconjunctivitis (EFK). Treatment adenoviral conjunctivitis. Tumors of the conjunctiva)

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