Bacterial

Mycoplasma genitalium

A common but under-recognised cause of urethritis, and a growing antibiotic-resistance worry.

What's at stake: Serious

Curable, but antibiotic resistance is rising fast; untreated infection can cause pelvic inflammatory disease.

Cause

Bacterium (M. genitalium)

Asymptomatic

Often

Curable

Yes, but resistance rising fast

Vaccine

Overview

Mycoplasma genitalium (often shortened to 'Mgen' or 'MG') is a small bacterium that infects the genital and urinary tract. Only recognised since the 1980s and only routinely testable more recently, it is now understood to be a frequent cause of non-gonococcal urethritis in men and cervicitis and pelvic inflammatory disease in women. General-population prevalence is around 1 to 2% in high-income countries. Its biggest concern is rapidly rising resistance to the antibiotics normally used to treat it.

How it spreads

Vaginal sex (both directions)
Anal sex, rectal infection occurs
Genital contact; less efficiently transmitted by oral sex
Sharing sex toys without cleaning

Symptoms

Often no symptoms at all
Discharge from the penis or vagina
Burning or pain when urinating
Pelvic pain or bleeding between periods (in women)
Rectal discomfort or discharge

Many infections cause no symptoms and clear or persist unnoticed. Testing uses a NAAT (the same kind of test as for chlamydia and gonorrhea), but is not always included in a standard panel, so ask if you have symptoms of urethritis or cervicitis.

Vaccine

No vaccine is currently available for Mycoplasma genitalium.

Treatment

Mgen is curable with antibiotics, but resistance to azithromycin is now common, so treatment increasingly uses resistance-guided regimens (e.g. doxycycline followed by moxifloxacin). Because of resistance, testing of cure and treating partners matter. Routine screening of people without symptoms is not currently recommended.

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Educational purposes only. Consult a healthcare provider for personal medical advice.