Q. What is chlamydia?
A. Chlamydial (“kla-mid-ee-uhl”) infection is one of the leading sexually transmitted diseases (STDs) in the United States today. The U.S. Centers for Disease Control and Prevention estimate that more than 4 million new cases occur each year. Pelvic inflammatory disease (PID), a serious complication of chlamydial infection, has emerged as a major cause of infertility among women of childbearing age. Genital chlamydial infection is caused by a bacterium, Chlamydia trachomatis, and is transmitted during vaginal or anal sexual contact with an infected partner. A pregnant woman may pass the infection to her newborn during delivery, with subsequent neonatal eye infection or pneumonia. The annual cost of chlamydial infections and their sequelae is estimated to exceed $2 billion.
Men and women with C. trachomatis may experience abnormal genital discharge or pain during urination. These early symptoms may be absent or very mild. If symptoms occur, they usually appear within 1 to 3 weeks after exposure. Chlamydia is known as a “silent disease” because up to 75% of infected women and up to 50% of infected men have no symptoms. As a result, the disease is not often diagnosed until complications develop.
In women, the bacteria initially attack the cervix (the opening of the uterus) and the urethra or urine canal. The few women with symptoms might have an abnormal vaginal discharge or a burning sensation when urinating. When the infection spreads to the fallopian tubes, some women still have no symptoms; others have lower abdominal pain, low back pain, nausea, fever, pain during intercourse, and bleeding between menstrual periods. Chlamydial infections can also result in PID. If the infection spreads past the cervix, permanent, irreversible damage can occur. Symptoms usually occur within 1 to 3 weeks of exposure.
In men, chlamydial infections may lead to pain or swelling in the scrotal area, which is a sign of epididymitis, an inflammation of a part of the male reproductive system located near the testicles. Left untreated, this condition, like PID in women, can cause infertility.
C. trachomatis can cause proctitis (inflamed rectum) and conjunctivitis (inflammation of the lining of the eye). The bacteria also have been found in the throat as a result of oral sexual contact with an infected partner. A particular strain of C. trachomatis causes an uncommon STD called lymphogranuloma venereum (LGV), which is characterized by prominent swelling and inflammation of the lymph nodes in the groin. Complications may follow if LGV is not treated.
Chlamydial infection is easily confused with gonorrhea because the symptoms of both diseases are similar and they often occur together. The most reliable way to diagnose chlamydial infection is for a clinician to send a sample of secretions from a patient’s genital area to a laboratory that will look for the organism using one of a wide variety of quick and inexpensive laboratory tests. Although attempting to grow the organism in specialized tissue culture in the laboratory is one of the most definitive tests, it is expensive and technically difficult to do and test results are not available for three or more days.
Scientists have developed several rapid tests for diagnosing chlamydial infection that use sophisticated techniques and a dye to detect bacterial proteins. Although these tests are slightly less accurate, they are less expensive, more rapid, and can be performed during a routine check-up. These tests use a process called molecular amplification to detect the organism in genital secretions. Recently, the U.S. Food and Drug Administration approved this process for detection of C. trachomatis in urine. This is a major step in diagnosing chlamydial infection because it can be used in settings where performing a pelvic examination is not convenient or not feasible, e.g., in college health units and at health fairs. Results from the urine test are available within 24 hours.
Doctors usually prescribe antibiotics such as a 1-day course of azithromycin or a 7-day course of doxycycline to treat chlamydial infection. Other antibiotics such as erythromycin or ofloxacin also are effective. Pregnant women can be treated with azithromycin or erythromycin. Amoxicillin is also a safe alternative for treating pregnant women. Penicillin, which is often used for treating some other STDs, is not effective against chlamydial infections. New medications are being developed that should greatly simplify treatment and help control the spread of C. trachomatis in the population.
A person with chlamydial infection should be sure to take all of the prescribed medication, even after symptoms disappear. If the symptoms do not disappear within 1 to 2 weeks after finishing the medicine, the patient should make a follow-up visit to the doctor or clinic. All sex partners of a person with chlamydial infection should be evaluated and treated to prevent reinfection and further spread of the disease.
Pelvic Inflammatory Disease, Possible Result of Chlamidial Infection
Each year up to 1 million women in the United States develop PID, a serious infection of the reproductive organs. As many as half of all cases of PID may be due to chlamydial infection, and many of these occur without symptoms. PID can result in scarring of the fallopian tubes, which can block the tubes and prevent fertilization from taking place. An estimated 100,000 women each year become infertile as a result of PID.
In other cases, scarring may interfere with the passage of the fertilized egg to the uterus during pregnancy. When this happens, the egg may implant in the fallopian tube. This is called ectopic or tubal pregnancy. This very serious condition results in the loss of the fetus and is a major cause of pregnancy-related death in the United States.
Effects of Chlamydial Infection in Newborns
A baby who is exposed to C. trachomatis in the birth canal during delivery may develop conjunctivitis (eye infection) or pneumonia. Symptoms of conjunctivitis, which include discharge and swollen eyelids, usually develop within the first 10 days of life. Symptoms of pneumonia, including a progressively worsening cough and congestion, most often develop within 3 to 6 weeks of birth. Both conditions can be treated successfully with antibiotics. Because of these risks to the newborn, many doctors recommend routine testing of all pregnant women for chlamydial infection.
Because chlamydial infection often occurs without symptoms, people who are infected may unknowingly pass the bacteria to their sex partners. Many doctors recommend that all persons who have more than one sex partner, especially women less than 25 years of age, be tested for chlamydial infection regularly, even in the absence of symptoms. Using condoms or diaphragms during sexual intercourse may help reduce the transmission of chlamydia.
Complications include serious reproductive and other health problems with both short and long-term consequences. The damage that chlamydia causes is often “silent,” too. Untreated chlamydia in men typicall causes urethral infection that sometimes spreads and can even lead to infertility. If untreated in women, this condition can spread into the uterus or fallopian tubes (egg canals) and in up to 40% of women cause PID. This disease can permanently damage your reproductive organs and lead to chronic pain, infertility, and potentially fatal ectopic pregnancies.
Pregnancy complications of chlamydial infections may include premature delivery and affecfted babies can get chlamydial infections in thier eyes and respiratory tracts (early infant pneumonia).
Thomas G. Stovall, M.D.
Dr. Stovall is a Clinical Professor of Obstetrics and Gynecology at the University of Tennessee Health Science Center in Memphis, Tennessee and Partner of Women’s Health Specialists, Inc.