Mycoplasma Genitalium Symptoms and Treatment

Mgen is a common bacterium linked to sexually transmitted infections

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Mycoplasma genitalium (Mgen) is a type of bacterium that is sexually transmitted. In natal females, it can cause vaginal itching, burning with urination, and bleeding of the skin around the vagina. In natal males, it can cause urethral discharge or burning with urination.

Mgen is the cause of several types of infections, including cervicitis and nongonococcal urethritis (NGU). It has also been associated with pelvic inflammatory disease (PID) and implicated in other infections once attributed to other bacteria. It is spread through unprotected sexual intercourse. Mgen is treatable, but if left untreated, it can cause complications.

This article will discuss the causes and symptoms of Mgen. It will also cover how Mgen is diagnosed and treated and what you can do to prevent it.

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What Causes an Mgen Infection?

Genital mycoplasma, also called Mgen, is a bacterium that can infect the human reproductive organs, including the penis and vagina. It can also infect the rectum.

Mgen is a common sexually transmitted infection. According to some estimates, up to 1% of people in developed countries are infected with Mgen. In developing countries, the incidence may be as high as 4%. Anyone can get Mgen, but it is more common in sex workers and in natal males who have sex with natal males than it is in other groups.

Mycoplasma Genitalium Symptoms

By and large, most cases of Mgen don't cause symptoms. If symptoms appear, they are primarily nonspecific and easily mistaken for other sexually transmitted infections (STIs) such as chlamydia and gonorrhea.

If symptoms do show up, they won't appear right away. Mgen has an incubation period of about four to eight weeks. Thus, it could be about a month or more between exposure to Mgen and the onset of symptoms.

Mycoplasma genitalium symptoms also differ in natal females and males. If symptomatic, males may experience urethral discharge or pain during urination (dysuria). In females, symptoms include pelvic pain, abnormal vaginal discharge, fever, nausea, vomiting, and potentially bleeding after sex.

As with other STIs, Mgen may also cause an unusual smell. Some people with Mgen notice a fishy odor, which tends to be more prominent after sex.

Mgen Symptoms in Women
  • Vaginal itching

  • Burning with urination

  • Pain during intercourse

  • Bleeding between periods or after sex

  • Possibly a fishy odor after sex and changes in vaginal discharge

Mgen Symptoms in Men
  • Urethral discharge

  • Burning with urination

How Is Mgen Spread?

The Mgen bacterium is spread through unprotected sexual intercourse. This can include vaginal and anal sex.

Some people have Mgen for years without knowing it. That's because most people do not develop symptoms. If you remain symptom-free, the infection may eventually resolve on its own, but you could still transmit the bacteria during the time you are infected.

Mgen Complications

Mgen can cause complications in both natal males and females. These can include:

  • Urethritis: This is an inflammation of the urethra, which is the tube that carries urine out of the body. People with this condition may experience pain with urination. After chlamydia, Mgen is the next most common cause of nongonococcal urethritis (NGU) in natal males. NGU is an inflammation of the urethra that is not caused by gonorrhea.
  • Cervicitis: Females with this condition experience inflammation and irritation of the cervix, which is the bottom part of the uterus.
  • Pelvic inflammatory disease (PID): This condition affects the female reproductive organs and can make it hard to become pregnant. PID can cause complications like scarring that blocks the fallopian tubes, ectopic pregnancy (pregnancy outside of the uterus), infertility (an inability to become pregnant), and long-term pelvic and/or abdominal pain.

Diagnosis

There is no approved blood test for diagnosing Mgen. A nucleic acid amplification test (NAAT) is the standard test for a diagnosis.

A NAAT uses urine and swab samples from the urethra, opening of the penis, part of the cervix, or vagina, and produces results in 24 to 48 hours.

If an NAAT is unavailable at a clinic, a healthcare provider might go ahead and diagnose Mycoplasma genitalium simply based on the fact that urethritis or cervicitis is persistent or recurrent. Studies show that 40% of such cases in natal males and up to 30% in natal females are caused by Mgen.

Role in Guiding Treatment

Syndromic treatment is when all STI cases that fit a certain profile of symptoms are treated the same without knowing their actual cause.

Healthcare providers who diagnose Mycoplasma genitalium based on symptoms alone and treat it accordingly may be right, but not always. That means that some people may have an entirely different infection that warrants a different treatment. Had the infection been properly identified from the start, the correct medication could have been started sooner.

NAAT is, therefore, the recommended testing method to diagnose a suspected case of Mgen. Your doctor can make specific treatment choices based on the results rather than trying something out based on an educated assumption.

Treatment

Mycoplasma genitalium is typically treated with antibiotics.

In the past, the most common form of treatment was a single 1-gram (g) dose of azithromycin. But Mgen may be becoming more resistant to first-line antibiotics like azithromycin and moxifloxacin. That means that the bacterium has mutated so that the drug is no longer effective.

Today, Mgen from a patient is tested to see whether or not the bacterium has mutated into a variant that is resistant to azithromycin. Results of that testing dictate the recommended treatment, which involves two seven-day courses of two different antibiotics:

  • Mgen has not mutated: 100 milligrams (mg) of doxycycline two times a day for seven days, followed by an initial 1 gram dose of azithromycin, then 500 milligrams of azithromycin daily for the next three days
  • Mgen has mutated: 100 milligrams of doxycycline two times a day for seven days, followed by 400 milligrams of moxifloxacin once daily for seven days

Preventing Mgen

Condoms are the best way to prevent Mgen, but it is still possible to get infected even if you use one. Once you have been diagnosed with the condition, it is important to avoid having sex for at least seven days after you begin treatment. This will help prevent passing the infection on to someone else.

Summary

Mycoplasma genitalium is a sexually transmitted infection caused by a bacterium. Many people don't know they have Mgen because they don't have symptoms. If symptoms occur, they can include burning with urination, pain, and abnormal discharge.

Treatment for Mgen involves antibiotics targeting the specific variant of the bacterium. Mgen can be prevented through protected sex with a condom. Contact a healthcare provider if you have have symptoms of Mgen or another STI. Also see a healthcare provider if your partner is showing signs of an STI.

7 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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  2. British Medical Journal. Mycoplasma Genitalium: easy to detect, hard to treat.

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Additional Reading

By Elizabeth Boskey, PhD
Elizabeth Boskey, PhD, MPH, CHES, is a social worker, adjunct lecturer, and expert writer in the field of sexually transmitted diseases.