Trachoma

Definition

Trachoma (truh-KO-muh) is a bacterial infection that affects the eyes. The bacterium that causes trachoma spreads through direct contact with the eyes, eyelids, nose or throat secretions of infected people. Trachoma is very contagious and almost always affects both eyes. Signs and symptoms of trachoma begin with mild itching and irritation of the eyes and eyelids and lead to blurred vision and eye pain. Untreated trachoma can lead to blindness.

Trachoma is the leading preventable cause of blindness worldwide. The World Health Organization (WHO) estimates that 8 million people worldwide have been visually impaired by trachoma. In Western countries, few people know about the disease, but in the poorest countries in Africa, prevalence among children can reach 40 percent.

If treated early, the prognosis for people with trachoma is excellent.

Symptoms

The principal signs and symptoms in the early stages of trachoma include:

  • Mild itching and irritation of the eyes and eyelids
  • Discharge from the eyes containing mucus or pus

As the disease progresses, later trachoma symptoms include:

  • Marked light sensitivity (photophobia)
  • Blurred vision
  • Eye pain

Young children are particularly susceptible to infection, but the disease progresses slowly, and the more painful symptoms may not emerge until adulthood.

The World Health Organization has identified a grading system with five stages in the development of trachoma. The stages are:

  • Inflammation — follicular. The infection is just beginning. Five or more follicles — small bumps that contain lymphocytes, a type of white blood cell — are visible with magnification on the inner surface of the upper eyelid (conjunctiva).
  • Inflammation — intense. In this stage, the eye is now highly infectious and becomes irritated, with a thickening or swelling of the upper eyelid.
  • Eyelid scarring. Repeated infections lead to scarring of the inner eyelid. The scars often appear as white lines when examined with magnification. The eyelid may become distorted and may turn in (entropion).
  • Trichiasis, or ingrown eyelashes. The scarred inner lining of the eyelid continues to deform, causing the lashes to turn in so that they rub on and scratch the transparent outer surface of the eye (cornea). Only about 1 percent of people with trachoma develop this painful condition.
  • Corneal clouding. The cornea becomes affected by an inflammation that is most commonly seen under the upper lid. Continual inflammation compounded by scratching from the in-turned lashes leads to clouding of the cornea. Secondary infection can lead to development of ulcers on the cornea and eventually partial or complete blindness.

All the signs of trachoma are more severe in the upper lid than in the lower lid. With advanced scarring, the upper lid may show an S-shaped curve. In addition, the lubricating glandular tissue in the lids — including the tear-producing glands (lacrimal glands) — can be affected. This can lead to extreme dryness, aggravating the problem even more.

When to see a doctor
Call your doctor if you or your child has itching, irritation or discharge from the eyes, especially if you recently traveled to an area where trachoma is common.

Causes

Trachoma is caused by certain subtypes of Chlamydia trachomatis, a bacterium that can also cause the sexually transmitted disease chlamydia.

Trachoma spreads through contact with discharge from the eyes or nose of an infected person. Hands, clothing, towels and insects can all be routes for transmission. In the world's developing countries, flies are a major means of transmission.

Risk factors

Factors that increase your risk of contracting trachoma include:

  • Poverty. Trachoma is primarily a disease of extremely poor populations.
  • Crowded living conditions. People living in close contact are at greater risk of spreading infection.
  • Poor sanitation. Poor hygienic conditions facilitate spread of the disease.
  • Age. In areas where the disease is endemic, it's most common in children ages 3 to 6.
  • Sex. Women contract the disease at higher rates than men do. Women are also blinded up to three times more often than men are.
  • Poor access to water. Households at greater distances from a water supply are more susceptible to infection.
  • Flies. People living in areas with problems controlling the fly population may be more susceptible.
  • Lack of latrines. Populations without access to working latrines — a type of communal toilet — have a higher incidence of the disease.

Complications

One episode of infection with Chlamydia trachomatis is easily treated with early detection and use of antibiotics. However, repeated infection can lead to complications, including:

  • Scarring of the inner eyelid
  • Eyelid deformities
  • Inward folding of the eyelid (entropion)
  • Ingrown eyelashes
  • Corneal scarring or cloudiness
  • Partial or complete vision loss

Preparing for your appointment

You're likely to start by seeing your family doctor or a general practitioner if you have symptoms of trachoma. However, in some cases when you call to set up an appointment, you may be referred immediately to an eye specialist (ophthalmologist).

Because appointments can be brief, and because there's often a lot of ground to cover, it's a good idea to be well prepared. Here's some information to help you get ready, and what to expect from your doctor.

What you can do

  • Be aware of any pre-appointment restrictions. At the time you make the appointment, be sure to ask if there's anything you need to do in the time leading up to your appointment. For example, if your child is the one with signs or symptoms of an eye condition, ask whether you should keep your child home from school or child care.
  • Write down any symptoms you're experiencing, including any details about changes in your vision. Are you light-sensitive? Has your vision become blurred? Would you say your eyes hurt or just that they itch?
  • Write down key personal information, including any trips you or someone close to you may have taken abroad. Also include information about any recent changes to corrective lenses, such as new contacts or glasses.
  • Make a list of all medications, as well as any vitamins or supplements, that you're taking.
  • Write down questions to ask your doctor.

Your time with your doctor is limited, so preparing a list of questions will help you make the most of your time together. List your questions from most important to least important in case time runs out. For eye irritation, some basic questions to ask your doctor include:

  • What is likely causing my symptoms?
  • Other than the most likely cause, what are other possible causes for my symptoms?
  • What kinds of tests do I need?
  • Is my condition likely temporary or chronic?
  • What is the best course of action?
  • Will I have any long-term complications from this condition?
  • Are there any restrictions that I need to follow, such as staying home from work or school?
  • Should I see a specialist? What will that cost, and will my insurance cover it?
  • Is there a generic alternative to the medicine you're prescribing me?
  • Are there any brochures or other printed material that I can take with me? What websites do you recommend visiting?

In addition to the questions that you've prepared to ask your doctor, don't hesitate to ask questions during your appointment at any time that you don't understand something.

What to expect from your doctor
Your doctor is likely to ask you a number of questions. Being ready to answer them may reserve time to go over points you want to spend more time on. Your doctor may ask:

  • Have you or someone close to you traveled abroad recently?
  • Have you ever had a similar problem?
  • Have you made any changes to your corrective lenses, such as wearing new contacts or using new contact lens solution?
  • When did you first begin experiencing symptoms?
  • How severe are your symptoms? Do they seem to be getting worse?
  • What, if anything, seems to improve your symptoms?
  • What, if anything, appears to worsen your symptoms?
  • Is anyone else in your household having similar symptoms?
  • Have you been treating your symptoms with any medications or drops?

What you can do in the meantime
While you are waiting for your appointment, practice good hygiene to reduce the possibility of spreading your condition:

  • Don't touch your eyes without first washing your hands.
  • Wash your hands thoroughly and frequently.
  • Change your towel and washcloth daily, and don't share them with others.
  • Change your pillowcase often.
  • Discard eye cosmetics, particularly mascara.
  • Don't use anyone else's eye cosmetics or personal eye-care items.
  • Discontinue wearing your contact lenses until your eyes have been evaluated; then follow your eye doctor's instructions on proper contact lens care.
  • If your child is infected, have him or her avoid close contact with other children.

Tests and diagnosis

Most people with trachoma in its initial stages display no signs or symptoms. In areas where the disease is endemic, a doctor can diagnose trachoma through a physical examination or through sending a sample of bacteria from your eyes to be cultured and tested in a laboratory.

Treatment and drugs

Trachoma treatment options depend on the stage of the disease.

Medications
In the early stages of trachoma, treatment with antibiotics alone may be enough to eliminate the infection. The two drugs currently in use include a tetracycline eye ointment and oral azithromycin (Zithromax). Although azithromycin appears to be more effective than tetracycline, azithromycin is more expensive. In poor communities, the drug used often depends on which one is available and affordable.

Surgery
Treatment of later stages of trachoma — including painful eyelid deformities — may require surgery. In eyelid rotation surgery (bilamellar tarsal rotation), a doctor makes an incision in the scarred lid and rotates the eyelashes away from the cornea. The procedure limits the progression of corneal scarring and can improve eyesight. Generally, this procedure can be performed on an outpatient basis. The procedure takes less than 15 minutes and has a good long-term success rate.

If the cornea has become clouded enough to seriously impair vision, corneal transplantation is an option that offers some hope of improved vision. Frequently, however, the results are not good.

Prevention

If you're traveling to parts of the world where trachoma is endemic, be sure to practice good hygiene to prevent infection.

If you've been treated for trachoma with antibiotics or surgery, reinfection is always a concern. For your protection and for the safety of others, be sure that family members or others you live with are screened and, if necessary, treated for trachoma.

Proper hygiene practices include:

  • Face washing. Keeping faces clean, especially children's, can help break the cycle of reinfection.
  • Controlling flies. Reducing fly populations can help eliminate a major source of transmission.
  • Proper waste management. Properly disposing animal and human waste can reduce breeding grounds for flies.
  • Improved access to water. Having a fresh water source nearby can help improve hygienic conditions.

Although no vaccine is available, trachoma prevention is possible. For instance, trachoma virtually disappeared in the United States by the 1950s due to improved sanitation and living conditions. The disease has also almost disappeared in certain countries, such as Morocco, where health organizations have been active in public education and have helped promote therapies known to cure the disease.

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