Chlamydia Test

Formal name: Chlamydia trachomatis

Related tests: Gonorrhoea

At a Glance

Why Get Tested?

To screen for or diagnose chlamydia infection

When to Get Tested?

If you are sexually active and have one or more risk factors for developing chlamydia, or have symptoms of infection e.g. discharge from the vagina or penis.

Sample Required?

A urine sample or a swab of cells or secretion from the infected area is required

The Test Sample

What is being tested?

The test is looking for evidence of infection by the bacterium Chlamydia trachomatis, the most common bacterial sexually transmitted disease (STD) in the United Kingdom.

How is the sample collected for testing?

Your doctor may use a swab to take a sample of cells or secretion from the infected area, or you may be asked to provide a urine sample. Women may be asked for a selftaken vaginal swab.

NOTE: If undergoing medical tests makes you or someone you care for anxious, embarrassed, or even difficult to manage, you might consider reading one or more of the following articles: Coping with Test Pain, Discomfort, and Anxiety, Tips on Blood Testing, Tips to Help Children through Their Medical Tests, and Tips to Help the Elderly through Their Medical Tests.

Another article, Follow That Sample, provides a glimpse at the collection and processing of a blood sample and throat culture.

The Test

How is it used?

The test is used in two ways:

to diagnose the cause of symptoms, and
to screen sexually active people for infection with the bacterium.

A definitive diagnosis is important because chlamydia can resemble gonorrhoea, and the two infections require different antibiotic treatment.

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When is it requested?

A doctor may request the test if you have symptoms such as vaginal discharge and abdominal pain (for women) or unusual discharge from the penis or pain on urination (for men). However, about 70% of infected women and 50% of infected men show no active symptoms, but can still infect a sexual partner without knowing. Risk factors for Chlamydia infection include age under 25 years, having new or multiple sexual partners, having sex with someone who has other partners, and not using barrier contraceptives such as condoms. You may wish, or your doctor may suggest, that you be screened for the infection if you have any these risk factors.

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What does the test result mean?

A positive test indicates an active infection that requires treatment with a course of antibiotics.

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Is there anything else I should know?

Chlamydia is often called “the silent epidemic” because infections are very common yet many people do not know that they are infected. Chlamydia is especially widespread among young people under the age of 25. A National Chlamydia Screening Programme is underway in England, to screen for the infection in asymptomatic sexually active men and women under 25 years of age. The aim of the programme is to reduce infection rates and spread of the disease, to so reduce the consequences of untreated infections.

Chlamydia is easily treated, but if left untreated, it can cause severe reproductive and other health problems, particularly in women. If you are infected, your sexual partner(s) should also be tested and treated as well.

People who are infected have a higher risk of developing other sexually transmitted diseases, including a 3 to 5 times greater risk of acquiring HIV if exposed to it.

The diagnosis of a sexually transmitted disease should not be ruled out if the test is negative; patients' clinical symptoms and history should also be considered.

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Common Questions

1. What are the symptoms of chlamydia?

Most infected people have no symptoms, so they do not seek treatment. For women, symptoms (if they occur) include bleeding between menstrual periods and after sexual intercourse, abdominal pain, painful intercourse, and an abnormal vaginal discharge. For men, symptoms include pus or milky discharge from the penis. Both sexes can experience painful or frequent urination.

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2. What will happen if I don’t get treated?

If left untreated, women may develop pelvic inflammatory disease (PID) from areas of infection that start on the cervix but that can spread to the fallopian tubes and ovaries. This can cause infertility infertility and increase the risk of , which may be fatal. Women who are infected and pregnant may experience heavy bleeding before delivery and premature rupture of the membranes. Men may develop pain and swelling of the testicles due to epidydimitis and may become sterile. Both sexes may develop rectal itching and red, swollen, itchy eyes and arthritis.

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3. How is chlamydia transmitted?

It is generally transmitted through sexual contact (oral, vaginal, or anal) with an infected partner. An infected mother can spread the disease to her baby during childbirth. These babies are in danger of developing conjunctivitis (an of the eyesthat can threaten eyesight) and pneumonia.

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4. How is it treated?

Chlamydia can be easily treated with a course of antibiotics.

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5. How can it be prevented?

Sexually active men and women can reduce their risk of chlamydia by reducing their numbers of partners and by using condoms correctly and consistently during sexual intercourse.

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NOTE: This article is based on research that utilizes the sources cited here as well as the collective experience of the Lab Tests Online Editorial Review Board. This article is periodically reviewed by the Editorial Board and may be updated as a result of the review. Any new sources cited will be added to the list and distinguished from the original sources used.