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Trachoma, which is also called granular conjunctivitis or Egyptian ophthalmia, is a contagious, chronic inflammation of the mucous membranes of the eyes, caused by Chlamydia trachomatis. It ischaracterized by swelling of the eyelids, sensitivity to light, and eventual scarring of the conjunctivae and corneas of the eyes.


Trachoma is a major cause of blindness in the world. It is found in the Far East, as well as countries with desert climates. In the United States, it is most common among certain Native Americans and in parts of Appalachia. The infection is highly contagious in its early stages. Blindness results from recurrent untreated infections.
The conjunctiva is the clear mucous membrane that lines the inside of the eyelid and covers the white part (sclera) of the eye. Conjunctivitis is an inflammation of the conjunctiva.

Causes and symptoms

Trachoma is caused by C. trachomatis, a parasitic organism closely related to bacteria. It is transmitted by insects, by hand-to-eye contact, or by the sharing of infected handkerchiefs or towels. The incubation period is about a week.
The early symptoms of trachoma include the development of follicles (small sacs) on the conjunctivae of the upper eyelids, pain, swollen eyelids, a discharge, tearing, and sensitivity to light. If the infection is not treated, the follicles develop into large yellow or gray pimples, and small blood vessels develop inside the cornea. In most cases, both eyes are infected.
Repeated infections eventually lead to contraction and turning-in of the eyelids, scarring of the corneas and conjunctivae, eventual blockage of the tear ducts, and blindness.


Diagnosis is based on a combination of the patient's history (especially living or traveling in areas with high rates of trachoma) and examination of the eyes. The doctor will look for the presence of follicles or scarring. He or she will take a small sample of cells from the patient's conjunctivae and examine them, following a procedure called Giemsa staining, to confirm the diagnosis.


Treatment of early-stage trachoma consists of four to six weeks of antibiotic treatment with tetracycline, erythromycin, or sulfonamides. Antibiotics should be given without waiting for laboratory test results. Treatment may combine oral medication with antibiotic ointment applied directly to the eyes. A single-dose treatment with azithromycin is an alternative method. Tetracyclines should not be given to pregnant women or children below the age of seven years.
Patients with complications from untreated or repeated infections are treated surgically. Surgery can be used for corneal transplantation or to correct eyelid deformities.


The prognosis for full recovery is excellent if the patient is treated promptly. If the infection has progressed to the stage of follicle development, prevention of blindness depends on the severity of the follicles, the presence of additional bacterial infections, and the development of scarring.


There are vaccines available that offer temporary protection against trachoma, but there is no permanent immunization. Prevention depends upon good hygiene and public health measures:
  • seek treatment immediately if a child shows signs of eye infection, and minimize his or her contact with other children
  • teach children to wash hands carefully before touching their eyes
  • protect children from flies or gnats that settle around the eyes
  • if someone has trachoma (or any eye infection), do not share towels, pillowcases, etc; Wash items well
  • if medications are prescribed, follow the doctor's instructions carefully



Riordan-Eva, Paul, et al. "Eye." In Current Medical Diagnosis and Treatment, 1998, edited by Stephen McPhee, et al., 37th ed. Stamford: Appleton & Lange, 1997.

Key terms

Conjunctivitis — Inflammation of the conjunctivae, which are the mucous membranes covering the white part of the eyeball (sclera) and lining the inside of the eyelids.
Cornea — The transparent front part of the eye that allows light to enter.
Ophthalmia — Inflammation of the eye. Usually severe and affecting the conjunctiva. Trachoma is sometimes called Egyptian ophthalmia.
Gale Encyclopedia of Medicine. Copyright 2008 The Gale Group, Inc. All rights reserved.


 [trah-ko´mah] (pl. tracho´mata)
a chronic infectious disease of the conjunctiva and cornea, producing photophobia, pain, and lacrimation, caused by an organism once thought to be a virus but now classified as a strain of the bacteria Chlamydia trachomatis. It is more prevalent in Africa and Asia than in other parts of the world; in North Africa few persons reach adulthood without having contracted the infection. It is fairly common in parts of the United States, such as in parts of the Southwest where a hot dry climate and scarcity of water encourage its spread. Trachoma in children and adults begins with a conjunctivitis that is marked by tiny follicles on the upper eyelids and tarsal plate. The follicles become larger and larger, and there is granulation of the cornea and impairment of vision. Eventually there is severe scarring which results in blindness. Trachoma is the world's leading cause of preventable blindness.

A condition closely related to trachoma in cause, manifestations, and epidemiologic pattern is inclusion conjunctivitis, which is fundamentally a sexually-transmitted disease of the adult genital tract. The agents of trachoma and inclusive conjunctivitis are called tric agents.
Treatment and Prevention. The drug of choice in treatment of trachoma is azithromycin; studies have demonstrated that a single oral dose eliminates the infection and prevents scarring. In areas where azithromycin is not available, tetracyclines may be used, administered topically in the form of suspensions or ointments that adhere to the conjunctiva for prolonged effect. Prevention of trachoma begins with an adequate water supply for washing the hands and bathing, control of flies, and education of the local population about the cause and spread of the disease. Early treatment of young children reduces the source of infection and avoids the complication of blindness. Repeated treatment programs for adults help control the spread of infection.
Miller-Keane Encyclopedia and Dictionary of Medicine, Nursing, and Allied Health, Seventh Edition. © 2003 by Saunders, an imprint of Elsevier, Inc. All rights reserved.


Chronic contagious microbial inflammation, with hypertrophy, of the conjunctiva, marked by the formation of minute grayish or yellowish translucent granules caused by Chlamydia trachomatis.
[G. trachōma, fr. trachys, rough, harsh]
Farlex Partner Medical Dictionary © Farlex 2012


A contagious disease of the conjunctiva and cornea, caused by the gram-negative bacterium Chlamydia trachomatis and characterized by inflammation, hypertrophy, and formation of granules of adenoid tissue. It is a major cause of blindness in Asia and Africa.

tra·cho′ma·tous (-kō′mə-təs) adj.
The American Heritage® Medical Dictionary Copyright © 2007, 2004 by Houghton Mifflin Company. Published by Houghton Mifflin Company. All rights reserved.


Ophthalmology An ocular infection by Chlamydia trachomatis which, if untreated, leads to blindness Incubation period 5 to 7 days, begins as a mild conjunctivitis that develops into a fulminant infection producing large amounts of discharge, and swollen eyelids; the initial stage lasts several wks, followed by a chronic stage in which the lids remain very swollen, the cornea becomes eroded, scarred, and vascularized; the lids develop contractures and may turn outward, pulling away from the eye; 2º bacterial infections may cause blindness. See Chlamydia trachomatis.
McGraw-Hill Concise Dictionary of Modern Medicine. © 2002 by The McGraw-Hill Companies, Inc.


Chronic inflammation and hypertrophy of the conjunctiva, marked by the formation of minute grayish or yellowish translucent granules, caused by Chlamydia trachomatis.
Synonym(s): Egyptian ophthalmia, granular ophthalmia.
[G. trachōma, fr. trachys, rough, harsh]
Medical Dictionary for the Health Professions and Nursing © Farlex 2012


An eye infection with the organism Chlamydia trachomatis , common in underdeveloped countries and responsible for millions of cases of blindness each year. The organism is spread by contact and by flies and causes severe inflammation of the CONJUNCTIVA, inturning of the upper lids, and secondary damage to the CORNEA, with opacification, ulceration and often perforation. Treatment with antibiotic ointments is effective.
Collins Dictionary of Medicine © Robert M. Youngson 2004, 2005


A chronic, bilateral, contagious conjunctivitis caused by the serotypes A, Ba and C of Chlamydia trachomatis. The conjunctivitis results in conjunctival scarring (Arlt's line) and may lead to entropion and trichiasis and dry eyes. Follicles at the limbus may leave some sharply defined depressions (Herbert's pits). There is also keratitis with corneal infiltrates, pannus and vascularization. As the disease progresses there is corneal ulceration and opacification, which may result in blindness. Trachoma is one of the main causes of blindness in the world. It is a disease most commonly encountered in hot regions of the globe where hygienic conditions are poor. Treatment includes a course of tetracycline or erythromycin and surgical correction of entropion and trichiasis may be necessary. Syn. egyptian conjunctivitis; granular conjunctivitis.
Millodot: Dictionary of Optometry and Visual Science, 7th edition. © 2009 Butterworth-Heinemann