Clinically reviewed by Dr. Pipat Finn, M.D., Senior Doctor, Doctor Pattaya. Last reviewed: August 2026
Mycoplasma genitalium is a sexually transmitted infection that most standard STD panels do not screen for. It can cause persistent discharge, pelvic pain, or no symptoms at all. Diagnosis requires a specific PCR or NAAT test, not a routine blood test. Doctor Pattaya offers this test alongside resistance-guided treatment, open 24 hours in South Pattaya.
You had a standard STD panel done. Everything came back negative. But something still feels off. The discharge has not fully cleared. There is still mild discomfort when you urinate. You were treated for what looked like chlamydia, it helped for a while, then the symptoms crept back. This situation comes through our doors regularly, and more often than not, the missing piece is mycoplasma genitalium.
Most clinics in Pattaya, and across Thailand, run a standard panel: gonorrhoea, chlamydia, syphilis, HIV. That covers a lot. But mycoplasma genitalium, often called Mgen, is not on that list. It is a urogenital infection that spreads the same way other STIs do, causes real damage if left untreated, and is genuinely difficult to treat once it becomes antibiotic-resistant. The fact that most people have never heard of it is exactly the problem.
What Is Mycoplasma Genitalium and Why Have You Never Heard of It?
Mgen infects the lining of the urethra, cervix, and reproductive tract. It was only identified in the early 1980s and did not make it onto standard screening panels in most countries until recently. In many places, including most tourist-area clinics in Southeast Asia, it still has not.
It spreads through vaginal and anal sex. It can coexist with chlamydia, which muddies the picture further, because treating one does not treat the other. Because most people with Mgen have no symptoms at all, it circulates quietly and goes untested for years.
Symptoms — Or Why Most People Have None at All
Most people carrying Mgen feel completely fine. Research suggests the majority of men with the infection have no symptoms. Among women, the asymptomatic rate is also significant. This is why it keeps spreading and why standard testing does not catch it.
When symptoms do appear in men, they usually look like urethritis: a clear or white discharge and a burning sensation when urinating. In women, symptoms are more varied: unusual discharge, pelvic pain, pain during sex, or bleeding between periods. These symptoms overlap with chlamydia and gonorrhoea, so without a specific test, Mgen gets missed entirely.
Persistent or recurring urethritis that does not respond to standard antibiotics is one of the clearest signals we see at this clinic. If you have been treated and the symptoms came back, Mgen should be on the list.
Why Standard STD Tests Miss Mycoplasma Genitalium
Standard STD tests are not designed to look for Mgen. A gonorrhoea and chlamydia swab, a syphilis blood test, an HIV screen: none of these will pick it up. The only reliable method is a PCR or NAAT test, which detects the organism’s genetic material directly.
Coinfection with chlamydia is more common than most people realise. A patient gets a positive chlamydia result, gets treated, feels better briefly, then symptoms return. In those cases, an undetected Mgen was likely running alongside the whole time. The chlamydia treatment did nothing for it.
We see this pattern often, particularly from patients who came to us after visiting other clinics in the Pattaya area. A negative result from a standard panel does not rule out Mgen. It just means nobody looked for it.
Antibiotic Resistance — Why the Wrong Treatment Makes Things Worse
This is where Mgen gets genuinely serious. Azithromycin, a common antibiotic used for chlamydia, used to be the go-to treatment for Mgen as well. The problem is that resistance to azithromycin has become widespread globally, and in the Asia-Pacific region, resistance rates are particularly high.
Using azithromycin without first checking for resistance does not just fail to cure the infection. It can make the infection harder to treat afterward by selecting for resistant strains. Current CDC guidance is clear on this: a single dose of azithromycin should not be used for Mgen anymore.
The recommended approach is two-stage antibiotic therapy. Doxycycline comes first, to reduce the bacterial load. Then, depending on the resistance profile, either moxifloxacin or azithromycin follows. Getting that sequence right matters, and that is why resistance-guided therapy is the standard we follow at Doctor Pattaya.
Complications if Mycoplasma Genitalium Goes Untreated
Left alone, Mgen causes real, lasting damage. In women, the main risks are cervicitis and pelvic inflammatory disease (PID). PID is painful, can cause scarring inside the fallopian tubes, and is one of the preventable causes of infertility and chronic pelvic pain. There is also an emerging association with preterm labour in pregnant women.
In men, untreated Mgen can lead to epididymo-orchitis, which is inflammation of the epididymis and testicle. This is painful and, if recurring, can affect fertility. None of this needs to happen. The infection is treatable when caught early and managed correctly.
Mycoplasma Genitalium in Pattaya — A Practical Note for Tourists and Expats
Pattaya has one of the most active visitor populations in Southeast Asia. No judgment here: we treat people from every walk of life, and this clinic has always been a no-questions-about-lifestyle zone. But the practical reality is that Mgen is a realistic exposure risk in any sexually active population, and most walk-in clinics and hotel doctor services in this area run only a standard STD panel.
A lot of long-term expats I see have been tested regularly for years and never once been offered an Mgen screen. That is not negligence: it is just that the test has not made it into routine practice in this part of Thailand yet. For tourists who had unprotected sex during a Pattaya trip and are now back home with symptoms their own doctor cannot explain, Mgen is often exactly what we find when we test specifically for it.
If you are in Pattaya now and concerned, walk in. We are open around the clock. If you have already left and are dealing with symptoms, it is still worth getting the right test wherever you are, and making sure whoever treats you knows about resistance-guided prescribing.
Getting Tested at Doctor Pattaya — What the Process Looks Like
Testing for Mgen is straightforward. For men, a urine sample is usually enough. For women, a vaginal or cervical swab is used. The sample goes for PCR analysis and results typically come back within a few days. We go through them with you clearly.
If the result is positive, we talk through the two-stage treatment plan and how long the course runs. A test of cure, meaning a retest after treatment to confirm the infection has cleared, is part of our standard follow-up. That step matters because Mgen has a real rate of treatment failure, and you want to know it actually worked.
Our STD testing and treatment service covers the full picture, including infections that standard panels miss. If you have had a test elsewhere and are still not getting answers, that is exactly the situation we are set up for.
Partner notification is something we talk through at the appointment as well. If your partner is still in Pattaya, getting them tested and treated at the same time is the cleanest solution. If they are already back in another country, we can advise on what to tell their doctor and which test to request. Reinfection from an untreated partner is the main reason treatment fails in otherwise well-managed cases.
Persistent symptoms after an STD test or treatment, unexplained discharge, or burning that keeps coming back: these are reasons to get a specific Mgen PCR test, not another standard panel. Doctor Pattaya is open 24 hours in South Pattaya and offers discreet walk-in STD testing including mycoplasma genitalium screening. Hotel visits are also available across Pattaya, Jomtien, and Naklua. Walk in at any time or contact us directly to book.
Frequently Asked Questions
Dr. Pipat Finn is the senior doctor at Doctor Pattaya Takecare Clinic, a 24/7 walk-in medical practice on South Pattaya Road, Chonburi, Thailand. They provide primary care, travel medicine, sexual health, vaccination, minor surgery, IV therapy, and emergency outpatient services for tourists, expatriates, and Pattaya residents. Languages: English and Thai. WhatsApp consultations: +66 95 073 5550. Call: +66 81 668 5557.
