What Is Trachoma?

Trachoma is a chronic infectious conjunctivitis keratitis caused by Chlamydia trachomatis. It is called trachoma because it forms a rough and uneven appearance on the surface of the eyelid and conjunctiva. In the early stage of the disease, the conjunctiva is infiltrated, such as nipple and follicular hyperplasia, and corneal ridges occur at the same time; in the later stage, the affected eyelid conjunctiva scars, causing deformity of the eyelid, aggravating corneal damage, which can seriously affect vision and even cause blindness. The incubation period is 5 to 14 days, and both eyes are diseased, which mostly occurs in children or adolescents.

Basic Information

English name: trachoma
Visiting department: Ophthalmology
Multiple groups: Children, teenagers
Common locations: eye

Common causes: Caused by Chlamydia trachomatis infection
Common symptoms: Foreign body sensation, photophobia, tears, mucus or mucopurulent discharge
Contagious: Have
way for spreading: contact

Causes of trachoma

This disease is a chronic infectious disease caused by Chlamydia trachomatis infection.

Clinical manifestations of trachoma

Chlamydia trachomatis mainly invades the palpebral conjunctiva, which may have congestion and blurred blood vessels, hypertrophy of the nipples, hyperplasia of follicles, corneal vasculature, and finally ends with scar formation.

(I) Stages of trachoma in China

1. Phase I (progressive period)

In the active phase, the nipples and follicles coexist, the upper fornix conjunctival tissue is blurred, and there is corneal vasculature.

2. Phase II (regression period)

From the beginning of the scar to the majority of the scar, only a few active lesions remain.

3. Stage III (full scarring stage)

The active lesions completely disappeared, replaced by scars, which were non-infectious. The classification criteria: according to how much the active lesion occupies the total area of the upper eyelid conjunctiva, it is divided into light (+), medium (++), and heavy (+++). ), Those who account for 1/3 to 2/3 are (++), and those who account for more than 2/3 are (++).

(II) The more commonly used method in the world is the MacCallan staging method

1. Phase I (Initial infiltration)

The palpebral conjunctiva and fornix conjunctiva are hyperemic and hypertrophic, especially above, with initial follicles and early corneal vasculature.

2. Phase II (active period)

There are obvious active lesions, namely nipples, follicles, and corneal blood vessels.

3. Stage III (pre-scarring)

Same as China's second period.

4. Stage IV (completely cicatricial phase)

Same as China's third period.

(Three) the classification method of corneal vasculature

The cornea is divided into four equal parts. The invasion within 1/4 of the blood vessel loop is (+), the number reaching 1/4 to 1/2 is (++), and the number reaching 1/3 to 3/4 is (++). +), More than 3/4 are (++++).

The clinical manifestations are mostly acute onset, the patient has a foreign body sensation, photophobia, tearing, and more mucus or mucopurulent discharge. After a few weeks, the acute symptoms subsided and entered the chronic phase. At this time, there was no discomfort or the eyes were easily fatigued. If healed or healed at this time, no scars would be left. However, in the chronic course, repeated infections often occur in endemic areas, and the condition becomes worse. When there is active vasculature on the cornea, the irritation symptoms become noticeable and vision loss occurs. In the later stages, the symptoms are more obvious due to sequelae, such as eversion of the eyelids, trichiasis, corneal ulcers, and dryness of the eyeballs, which seriously affect vision and even blindness.

Acute trachoma

Presents symptoms of acute follicular conjunctivitis, red and swollen eyelids, and high congestion of the conjunctiva. Due to nipple hyperplasia, the conjunctiva is rough and uneven, the upper and lower fornixes are full of follicles, combined with diffuse keratitis and anterior ear lymphadenopathy, which can be changed after a few weeks. For the chronic phase.

2. Chronic trachoma

Due to repeated infections, the course of the disease is prolonged for several years to more than ten years, the degree of congestion is reduced, there are nipple hyperplasia and follicle formation, the follicles are of different sizes, and can be gelatinous. Also found in the lower eyelid conjunctiva and lower fornix conjunctiva, in severe cases can even invade the semilunar folds.

Trachoma examination

Etiological detection

(1) Smear detection of chlamydia inclusion bodies is the most commonly used screening method and can be used for screening high-risk populations.

(2) Cell culture method It is considered as the gold standard for detection of Chlamydia trachomatis, but it is time-consuming and requires certain equipment technical conditions.

2. Molecular biology methods

Detection of Chlamydia trachomatis DNA in cervical or rectal biopsy specimens by in situ hybridization can also be detected by PCR, which can significantly improve the detection sensitivity, and can be used to identify its species and serotypes, and can be used for diagnosis, efficacy judgment and epidemiological investigation.

The PCR method can be used to evaluate the efficacy after diagnosis and treatment, but it should be noted that during the follow-up of the efficacy after discontinuation of the drug, some of the antigens were found to be negative by direct immunofluorescence, but the PCR method was still positive, which may be residual pathogenic DNA. In the body, it does not indicate the presence of a pathogen.

Differential diagnosis of trachoma

Conjunctival follicular disease

Common in children. Both sides are bilateral and there are no symptoms. Follicles are more common in the lower fornix and lower eyelid conjunctiva. Follicles are smaller, the size is similar, translucent, and the realm is clear. The conjunctiva between the follicles is normal, non-hyperemia and no corneal blood vessels Alas, no scars occurred.

2. Chronic follicular conjunctivitis

Common in school-age children and adolescents. Both are bilateral, and granulobacteria may be the cause. There are often secretions in the morning and discomfort in the eyes. Follicles are more common in the lower fornix and the lower eyelid conjunctiva, but they are not hypertrophic. After 1 to 2 years, they self-heal without scar formation.

3. Spring conjunctivitis

The disease is seasonal. The main symptoms are itchy eyes. The nipples on the eyelid conjunctiva are large, flat, and stiff. There is no disease in the upper vault. Eosinophils can be seen in the secretion smear.

4. Inclusion body conjunctivitis

With acute onset, the follicles are all under the fornix and the lower eyelid conjunctiva, without corneal vascular crests, and can heal within a few months to one year without forming scars.

Trachoma complications

Severe trachoma often has sequelae and complications, which are harmful to vision. Common cases include varus and trichiasis, trachoma corneal ulcers, ptosis, trachoma xerophthalmia, lacrimal duct obstruction and chronic dacryocystitis, blepharophesion, The cornea is cloudy.

Trachoma treatment

Drug treatment

Chlamydia trachomatis is sensitive to tetracycline family, macrolides and fluoroquinolones. For topical application, use 0.1% rifampicin or 15% sodium sulfaacetate eye drops, and tetracycline ointment or erythromycin ointment at night. Acute or severe trachoma should be treated with antibiotics throughout the body. Doxycycline or erythromycin can be administered orally.

2. Surgical treatment

It is used for ocular complications, such as severe varus trichiasis, purulent lymphadenitis caused by venereal lymphogranuloma, and elephantiasis.

Trachoma prevention

Chlamydia trachomatis is often attached to the secretions of patients' eyes. Any contact with this secretion can cause trachoma to spread infection. Therefore, publicity and education should be strengthened to cultivate good hygiene habits. Do not rub your eyes with your hands, wash and dry towels and handkerchiefs frequently; treat trachoma patients actively and pay attention to clean water.