Chlamydiae are similar to bacteria but cannot produce their own energy and thus live in the cells of other organisms. Once inside the host cell, chlamydiae replicate and form inclusion bodies. They then replace and finally destroy the cell membrane of the host, releasing more chlamydiae to continue the infection process. The life cycle of chlamydia is 72 hours. Chlamydiae are found in parts of the body with a mucosal membrane, which are the eye, the respiratory tract, and the genitourinary tract.
Transmission
Neonatal inclusion conjunctivitis develops within five to 12 days after birth and is contracted as the child passes through the mother's cervix. Two-thirds of those females with a chlamydial infection pass the infection on to the child during childbirth.
Adult inclusion conjunctivitis, which can affect sexually active adolescents, is usually transmitted sexually and develops when the eye is infected by the urogenital secretions of an individual infected with chlamydia, but it can be transmitted by eye-to-eye contact. Symptoms do not always exist with chlamydial infections, and thus it is often transmitted unknowingly. Up to 80 percent of female adults and adolescents with inclusion conjunctivitis are asymptomatic, and almost half of those with adult inclusion conjunctivitis do not have a systemic infection of chlamydia.
Demographics
The exact number of individuals with adult inclusion conjunctivitis is not known. But adult inclusion conjunctivitis, which is seen only if one is infected with chlamydia, affects 3 million annually in the United States. It is seen most often in sexually active 15 to 30 years olds, and most of these infections are reported in women 15 to 19. Forty-six percent of new cases of chlamydia fall within this group. Up to 10 percent of pregnant women harbor the chlamydial parasite. Twenty-five percent of those men with chlamydia infections are not aware of their infection.
Up to 6 percent of newborns develop neonatal inclusion conjunctivitis. Forty percent of neonatal conjunctivitis is due to chlamydia. Between 35 and 50 percent of newborns infected with chlamydia develop neonatal inclusion conjunctivitis. Neonatal chlamydial or inclusion conjunctivitis is 10 times more common than neonatal gonorrheal conjunctivitis.
Causes and symptoms
Inclusion conjunctivitis is caused by an intracellular organism called Chlamydia trachomatis.
The signs and symptoms of adult inclusion conjunctivitis appear two to 19 days after contact with an individual who harbors the chlamydia parasite. The symptoms of adult inclusion conjunctivitis are a foreign body sensation, watery eyes, and eyelids that stick together upon awakening. Large follicles may be seen if the lower lid is pulled down. The lymph nodes near the ears, called the preauricular nodes, may be swollen. Because the symptoms of chlamydia wax and wane and because the
adolescent or adult may be asymptomatic, proper diagnosis may be delayed.
The signs of neonatal inclusion conjunctivitis appear five to 14 days after birth. Since the lymphatic system of the newborn is not well developed, follicles will not usually be present, and the lymph nodes will not be enlarged, but the eye of the neonate with chlamydia will be red and inflamed. The infant will be tearing and have a purulent ocular discharge, and the eyelids will be swollen. Other accompanying symptoms in the infant include a cough and rhinitis.
When to call the doctor
Any red eye, with or without discharge, should be examined by an appropriate healthcare practitioner. There are many causes of eye problems, and appropriate treatment should be instituted as soon as possible if inclusion conjunctivitis is the cause of the ocular problem.
The children of mothers who give birth outside the traditional hospital setting should contact their healthcare provider regarding the necessity of prophylactic antibiotic drops. A healthcare provider should be informed if the mother or father of a newborn has an untreated sexually transmitted disease.
Diagnosis
The diagnosis of inclusion conjunctivitis cannot be made definitively without laboratory testing, but the signs of inclusion conjunctivitis can be seen by the eye care provider, even if a patient is not symptomatic. Follicles can seen on the inside inferior eyelids and occasionally under the superior eyelid of the patient with adult inclusion conjunctivitis, and if treatment has been delayed, scarring of the interior of the eyelids may be present as well as kerititis, an inflammation of the cornea, and neovascularization, or new blood vessel formation of the cornea. Upon questioning the individual may report a history of a genitourinary infection.
The laboratory testing for inclusion conjunctivitis begins with swabbing a sample from the inside of the eyelids to test for the presence of the characteristic inclusion bodies made only by chlamydia. The Giemsa stain is used often to diagnose neonatal inclusion conjunctivitis. This technique has a high rate of false positives for the adult with inclusion conjunctivitis. Immunofluorescence monoclonal antibody testing is very sensitive technique that gives a rapid diagnosis of inclusion conjunctivitis. Other techniques used to diagnose a chlamydial infection are enzyme immunoassays, serum antibody tests, and DNA probes.
Since inclusion conjunctivitis can mimic other diseases, it is important to rule out other types of conjunctivitis, such as those of viral etiology or allergy or those caused by gonorrhea.
Treatment
Neonatal inclusion conjunctivitis may resolve spontaneously within nine months without treatment. But the standard treatment for an infant younger than four months of age is oral erythromycin, four times a day for two weeks. The eye may be irrigated with saline to help remove the mucus discharge. The parents of the infant are treated as well.
Doxycycline, tetracycline, ocufloxacin, and erythromycin are sometimes prescribed. Tetracycline is not given to children under eight years of age, and ocufloxacin is not given to those under 18 years of age. Neither drug is given to pregnant or nursing women because of side effects. Topical antibiotics are not required if systemic or oral medication is prescribed, but if there is a co-existing inflammation in the eye, then topical steroids may be given. Finally, the sexual partners of individuals with inclusion conjunctivitis must also be receive antibiotic treatment.
Prognosis
Usually adult inclusion conjunctivitis resolves within two to four weeks with treatment. Rarely does inclusion conjunctivitis lead to blindness, unless it has been left untreated for months or longer. If untreated, a chlamydial infection can lead to pelvic inflammatory disease and scarring of fallopian tubes in women, causing infertility or ectopic pregnancies. In males, urethritis may result.
Ten to 20 percent of infants infected with chlamydia develop pneumonia during the first six months of life. In the infant, inclusion conjunctivitis may persist for several years.
Prevention
Since in the United States adult inclusion conjunctivitis is primarily a sexually transmitted disease, the incidence of inclusion conjunctivitis can be decreased either through abstinence or through the use of condoms. Pregnant women with a chlamydial infection should talk to their doctor about treatment of the infection. Antibiotic eye drops only may not be sufficient to prevent inclusion conjunctivitis in the newborn if the mother is infected with chlamydia.
The incidence of neonatal conjunctivitis can be reduced by applying erythromycin ointment to the newborn's eyes shortly after delivery. Silver nitrate, which may be instilled at some institutions at birth (instead of erythromycin), is not effective against chlamydia.
Parental concerns
In the newborn, inclusion conjunctivitis may resolve spontaneously, but there are chlamydial infections which can cause blindness if not treated. So, any eye problem in the newborn needs to be diagnosed properly and treated as indicated by the pediatrician or eye-care provider.
When inclusion conjunctivitis is diagnosed in an adolescent, it is almost always has been contracted through sexual activity. Sixty-five percent of adolescents have had sexual intercourse by age 16. Only 40 percent of young adults between 18 and 21 years of age used a condom during their most recent sexual encounter, and 45 percent of these individuals have already had more than three sexual partners. Because peer pressure makes it difficult to resist sex and because adolescents have difficulty understanding they are risks of contracting sexually transmitted diseases, including chlamydial infections, parents should be involved in helping the adolescent understand these risks.
KEY TERMS
Chlamydia—The most common bacterial sexually transmitted disease in the United States. It often accompanies gonorrhea and is known for its lack of evident symptoms in the majority of women.
Conjunctiva—Plural, conjunctivae. The mucous membrane that covers the white part of the eyes (sclera) and lines the eyelids.
Cornea—The clear, dome-shaped outer covering of the eye that lies in front of the iris and pupil. The cornea lets light into the eye.
Gonorrhea—A sexually transmitted disease that causes infection in the genital organs and may cause disease in other parts of the body.
Trachoma—A type of chlamydia that causes blindness.
BOOKS
Adamis, Anthony P., et al. "Chlamydia and Acanthamoeba Infections of the Eye." In Principles and Practice of Ophthalmology. Philadelphia: Saunders, 2000.
Dawson, Chandler R. "Inclusion Conjunctivitis." In Current Ocular Therapy. Philadelphia: Saunders, 2000.
Frangie, John P. "Conjunctivitis." In Conn's Current Therapy. Philadelphia: Elsevier Inc., 2004.
PERIODICALS
Cothran, Mary M., and Joyce P. White. "Adolescent Behavior and Sexually Transmitted Diseases: The Dilemma of Human Papillomavirus." Health Care for Women International 23 no. 3 (April-May 2002): 306–19.
WEB SITES
"Neonatal Conjunctivitis." Medline Plus. Available online at <www.nlm.nih.gov/medlineplus/print/ency/article/001606.htm> (accessed November 29, 2004).
