Chlamydia is the most common of all of the sexually transmitted diseases. It is caused by the small intracellular bacterium Chlamydia trachomatis. This organism can cause infections in the vagina, urethra, throat and anus so all forms of unprotected intimate sexual activity with an infected partner can lead to infection. A newborn infant whose mother carries the infection may be infected during vaginal delivery.
Many patients infected with C. trachomatis will be asymptomatic. About 75% of infected women and 50% of men show no symptoms at all. Symptoms that women can show include cystitis, vaginal discharge and mild abdominal pain. Men may have a urethral discharge or irritation at the tip of the penis. Anal infections in both sexes can give rise to a discharge, rectal bleeding or rectal pain. Infections in the throat are rarely symptomatic but the person may have a sore throat.
Untreated infections can impact on a person’s fertility. Women may develop Pelvic Inflammatory Disease (PID), which can damage the fallopian tubes leading to infertility or an increased risk of ectopic pregnancy. Men rarely have any complications but sometimes it can cause epididymo-orchitis causing pain and redness on one or both sides of the scrotum. Occasionally this can lead to sterility. Very rarely chlamydia can cause Reiter’s syndrome, which is characterized by arthritis with skin lesions as well as eye and urethral inflammation.
Diagnosis and treatment of chlamydia infections in their early stages will prevent the danger of any complications.
Because the symptoms of chlamydia are non-specific and may be absent, diagnosis requires the laboratory testing of the appropriate samples. Vaginal, cervical, urethral, rectal and throat swabs are all suitable for testing. Urine samples are also suitable for testing particularly from men.
Chlamydia is an intracellular bacterium and cannot be grown on artificial media. It is possible to grow the organism in cultured cell lines. As cell culture takes time and is very labor-intensive, clinical samples are usually tested with direct antigen detection methods. Most diagnostic laboratories will use either the polymerase chain reaction or an enzyme linked immuno assay to detect chlamydia. These methods will give a quicker diagnosis than cell culture methods.
In symptomatic males with a urethral discharge, a gram stain of a smear made from the discharge may allow a rapid diagnosis. Chlamydia is too small to be visualized by normal light microscopy. The presence of pus cells in a urethral smear without any visible bacteria is indicative of chlamydial infection. Laboratories attached to sexually transmitted diseases clinics frequently use this test to enable suitable treatment to start on the day of the first appointment. Unfortunately, this test is not suitable for diagnosis of chlamydia infections in women as many beneficial bacteria colonize the vagina. For the same reason it cannot be used for the diagnosis of rectal or oral chlamydial infections in either men or women.
Chlamydia infections are treated with antibiotics. A single one-gram dose of the macrolide antibiotic azithromycin (Zithromax, Clamelle) will treat chlamydia. The tetracycline antibiotic doxycycline (Vibramycin) can also be used. A 100-milligram capsule of doxycycline taken twice a day for a week treats chlamydia. All sexual contacts of an infected person should be treated at the same time to prevent re-infection. Qualified medical advice should be obtained before starting any medication.