Can I Get Chlamydia From Anal Sex?

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Anal chlamydia trachomatis infections are not often discussed or tested for. Despite that, they may be a real problem. A 2009 study of HIV positive gay men in Switzerland found that more than 10 percent had rectal chlamydia infections. A similar prevalence of rectal chlamydia infection was found in an Amsterdam based study of men and women who reported receptive anal intercourse. 

Still, chlamydia is primarily thought of as an issue for women.

That's because of its association with pelvic inflammatory disease and infertility. However, this extremely common STD can also cause significant health problems for men. Routine STD screening usually includes a chlamydia swab, or urine test, for just this reason. However, even that won't catch all cases of the disease. Why? Because they aren't looking for rectal chlamydia. Anal chlamydia exists, and when it does it may be an unrecognized problem. That's because doctors don't always ask whether people practice anal sex. Then, due to a lack of recognition of how common anal sex is, they don't test for anal STDs. 

Anal Chlamydia Is One Possible Result of Unprotected Anal Sex

Men and women who practice unprotected receptive anal sex are at risk of acquiring anal chlamydia infections. These infections, also known as rectal chlamydia infections, are problematic in their own right. They may also increase an individual's risk of acquiring HIV.

Fortunately, anal chlamydia trachomatis should be largely, if not entirely, preventable by the routine practice of safe anal sex. That means using condoms every time you have anal intercourse. It also means using the right lubricant with those condoms. 

How Is Anal Chlamydia Detected?

As with other types of chlamydia, the majority of anal chlamydia infections are asymptomatic.

Anal chlamydia infections can, however, cause proctitis and related rectal symptoms. For example, it can lead to pain with bowel movements. It can also cause rectal bleeding and pain. Severe cases of LGV chlamydia can even lead to chronic diarrhea. (LGV chlamydia is also known as lymphogranuloma venereum.

The best chlamydia tests look directly for evidence of the organism, rather than for an immune response against it. Therefore, testing for rectal chlamydia requires that the anus is swabbed. Unlike a urethral swab, a rectal/anal swab causes minimal discomfort in most individuals. Research has shown that swabs can even be effectively taken by patients themselves. Unfortunately, this is not yet an accepted standard of care.

Once a sample is taken, the swab can be tested for chlamydia trachomatis. The test used for this is the same one that would be used at any other anatomic site.Therefore any doctor that does a swab test for vaginal, urethral, or oral chlamydia should also be able to test for anal chlamydia

If you are a man or woman who practices unprotected receptive anal sex, tell your doctor. That way you can discuss with them whether rectal STD testing would be a good idea. Tests for anal STDs should include both gonorrhea and chlamydia tests.

Depending on your risk, an anal pap may be a good choice as well.

How Is Anal Chlamydia Treated?

Just as with other forms of chlamydia, anal chlamydia is treated with antibiotics. Chlamydia trachomatis infections are usually treated with a single dose of azithromycin or 7 days of doxycycline. Lymphogranuloma Venerum is usually treated with 21 days of doxycycline. These are the same recommendations as for other chlamydia infections. 

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