Mycoplasma Genitalium: The Hidden STI You Need to Know About

Mycoplasma genitalium (MG) is an emerging sexually transmitted infection that often goes undiagnosed due to its subtle symptoms or lack thereof. This bacterial infection can cause urethritis in men and cervicitis, pelvic inflammatory disease, and fertility issues in women. Despite being more common than gonorrhea in many populations, MG testing is not routinely included in standard STI screenings, creating challenges for diagnosis and treatment, especially as antibiotic resistance increases.

What is Mycoplasma Genitalium?

Mycoplasma genitalium (often abbreviated as MG or Mgen) is one of the smallest known bacteria capable of self-replication. First discovered in 1981, it has only recently gained recognition as an important sexually transmitted infection. The bacterium primarily infects the urogenital tract, including the urethra in men and the cervix in women.

MG is characterized by several key features that make it unique among STIs:

• Cell wall deficiency: Unlike many bacteria, MG lacks a traditional cell wall, making it naturally resistant to certain antibiotics like penicillin and other beta-lactams.

• Slow growth: The bacterium multiplies extremely slowly compared to other bacteria, which contributes to both chronic infections and the development of antibiotic resistance.

• Adhesion properties: MG has specialized structures that allow it to attach firmly to epithelial cells in the genital tract, making it difficult for the body to clear the infection naturally.

Research suggests that MG may be responsible for approximately 15-20% of non-gonococcal urethritis cases in men and 10-30% of cervicitis cases in women. Despite this prevalence, awareness remains limited among both healthcare providers and patients.

How Common is Mycoplasma Genitalium?

Studies indicate that Mycoplasma genitalium is surprisingly common, with global prevalence estimates varying by population:

• General population: Approximately 1-3% of adults

• Among people seeking STI testing: 4-38%, depending on the population studied

• Among patients with urethritis symptoms: 15-25%

• Among patients with cervicitis: 10-30%

In many settings, MG is more prevalent than gonorrhea but less common than chlamydia. However, exact prevalence is difficult to determine because:

1. MG is not a reportable disease in most countries

2. Testing is not routinely performed in standard STI panels

3. Many infections are asymptomatic and go undetected

The infection is most common among young adults aged 18-35, particularly those with multiple sexual partners or inconsistent condom use. Studies suggest that MG infection rates may be higher in certain demographic groups and in settings with limited access to comprehensive STI testing.

Signs and Symptoms of Mycoplasma Genitalium

One of the challenges in identifying Mycoplasma genitalium infections is that approximately 70% of infected individuals show no symptoms. When symptoms do occur, they can vary considerably between men and women.

Symptoms in Men

• Urethritis: Inflammation of the urethra causing:

  • Painful or burning urination (dysuria)

  • Clear or white discharge from the penis

  • Itching or irritation at the tip of the penis

  • Discomfort that may be intermittent or persistent

• Proctitis: Inflammation of the rectum in men who have receptive anal sex

  • Rectal pain or discomfort

  • Discharge from the rectum

  • Bleeding or spotting from the rectum

• Epididymitis: Less commonly, MG can cause inflammation of the epididymis

  • Pain and swelling in the testicles

  • Discomfort during sexual activity

Symptoms in Women

• Cervicitis: Inflammation of the cervix causing:

  • Abnormal vaginal discharge

  • Spotting between periods or after sex

  • Pain during intercourse (dyspareunia)

  • Lower abdominal discomfort

• Pelvic Inflammatory Disease (PID): If the infection spreads to the upper reproductive tract:

  • Severe pelvic or abdominal pain

  • Fever and general malaise

  • Irregular menstrual bleeding

  • Pain during urination

• Urethritis: Less commonly in women:

  • Painful urination

  • Increased urinary frequency or urgency

Complications of Untreated Infection

If left untreated, Mycoplasma genitalium infection can lead to serious complications:

In women:

• Pelvic inflammatory disease (PID)

• Increased risk of ectopic pregnancy

• Tubal factor infertility

• Chronic pelvic pain

• Potentially increased susceptibility to other STIs, including HIV

In men:

• Reactive arthritis (rare)

• Possible contribution to male infertility (still being researched)

• Chronic prostatitis/chronic pelvic pain syndrome

During pregnancy:

• Some studies suggest associations with preterm birth, spontaneous abortion, and other adverse pregnancy outcomes, though more research is needed

How is Mycoplasma Genitalium Transmitted?

Mycoplasma genitalium is primarily transmitted through sexual contact. The main transmission routes include:

1. Vaginal intercourse: The most common route of transmission

2. Anal intercourse: Particularly for rectal infections

3. Potentially through other intimate sexual contact: Though less efficient than penetrative sex

Unlike some other STIs, Mycoplasma genitalium is not typically transmitted through:

• Kissing

• Casual contact

• Sharing towels or toilet seats

• Swimming pools or hot tubs

The risk of transmission is influenced by several factors:

• Condom use: Consistent and correct condom use significantly reduces transmission risk

• Number of sexual partners: Risk increases with multiple partners

• Presence of other STIs: Co-infections may increase susceptibility

• Duration of exposure: Longer sexual relationships with an infected partner increase transmission probability

It's important to note that since MG can remain asymptomatic for long periods, people may unknowingly transmit the infection to partners.

Testing for Mycoplasma Genitalium

Testing for Mycoplasma genitalium has historically been challenging, which has contributed to its under-recognition. However, diagnostic options have improved significantly in recent years.

Current Testing Methods

1. Nucleic Acid Amplification Tests (NAATs)

   • The gold standard for MG detection

   • Uses PCR (polymerase chain reaction) technology to detect the genetic material of the bacterium

   • Highly sensitive and specific

   • Can be performed on urine samples, urethral swabs, cervical swabs, or vaginal swabs

2. Resistance Testing

   • Some advanced tests can simultaneously detect MG and identify antibiotic resistance markers

   • Particularly important for macrolide resistance, which affects treatment success rates

   • Not universally available but becoming more common in specialized settings

Who Should Get Tested?

Current guidelines generally recommend testing for Mycoplasma genitalium in:

• Symptomatic individuals:

  • Men with persistent or recurrent urethritis

  • Women with cervicitis that doesn't respond to standard treatment

  • Women with pelvic inflammatory disease

  • Anyone with unexplained genital symptoms after other common STIs have been ruled out

• Higher risk scenarios:

  • Sexual partners of individuals with confirmed MG infection

  • In some cases, as part of comprehensive STI screening for high-risk individuals

Where to Get Tested

Testing for Mycoplasma genitalium is not universally available at all healthcare facilities. Your options include:

• STI clinics: Specialized sexual health clinics are most likely to offer MG testing

• Urology or gynecology specialists: May offer testing when symptoms persist despite treatment for other conditions

• STDCheck: Our partner offering comprehensive STI testing including Mycoplasma genitalium with convenient locations nationwide

• Some primary care providers: Though availability varies widely

When seeking testing, it's important to specifically request Mycoplasma genitalium testing, as it is not typically included in standard STI panels at most facilities.

Treatment for Mycoplasma Genitalium

Treatment of Mycoplasma genitalium has become increasingly complex due to rising antibiotic resistance. Current approaches focus on targeted therapy based on resistance patterns where possible.

First-Line Treatment Options

The recommended treatment typically follows a two-step approach:

1. Doxycycline (100mg twice daily for 7 days)

   • Used first to reduce bacterial load

   • Followed by:

2. Azithromycin (1g initially, then 500mg daily for 3 days) or Moxifloxacin (400mg daily for 7-10 days)

   • Selection depends on suspected resistance patterns

Antibiotic Resistance Concerns

Mycoplasma genitalium has shown alarming rates of resistance development:

• Macrolide resistance: Rates of resistance to azithromycin have reached 50-80% in some regions

• Fluoroquinolone resistance: Emerging resistance to moxifloxacin is increasingly reported

• Multi-drug resistance: Some strains show resistance to multiple antibiotic classes

These resistance patterns make treatment increasingly challenging and highlight the importance of:

• Resistance testing when available

• Adherence to treatment guidelines

• Completion of prescribed antibiotic courses

• Follow-up testing to confirm cure

Post-Treatment Recommendations

After completing treatment for Mycoplasma genitalium:

• Test of cure: Should be performed 3-4 weeks after completing treatment

• Sexual abstinence: Avoid sexual contact until both you and your partner(s) complete treatment and are confirmed cured

• Partner notification: All recent sexual partners should be informed and tested/treated

• Re-testing: Consider re-testing after 3 months, especially if symptoms persist

Prevention of Mycoplasma Genitalium

Preventing Mycoplasma genitalium follows similar principles to preventing other STIs:

Barrier Methods

• Condoms: Consistent and correct use of external (male) condoms provides significant protection during vaginal and anal intercourse

• Dental dams: May provide protection during oral-genital contact, though MG transmission through this route is less common

• Internal condoms: Can be used as an alternative barrier method

Other Prevention Strategies

• Regular testing: For sexually active individuals with multiple partners

• Communication: Open discussions about STI status with partners

• Mutual monogamy: Limiting sexual activity to one uninfected partner reduces risk

• Reducing number of sexual partners: Fewer partners generally means lower exposure risk

If You're Diagnosed with MG

• Complete the full course of antibiotics: Even if symptoms improve

• Abstain from sexual activity: Until treatment is complete and infection is cleared

• Ensure partners are tested and treated: To prevent reinfection

• Consider routine testing: If you're in a high-risk group

Long-term Health Implications

Research on the long-term consequences of Mycoplasma genitalium infection is still evolving, but several concerns have been identified:

Reproductive Health Impacts

• Female fertility: MG has been associated with tubal factor infertility

• Pregnancy complications: Some studies suggest links to preterm birth and other adverse outcomes

• Chronic inflammation: Long-term infection may cause chronic inflammation of reproductive organs

Association with Other Conditions

Emerging research is investigating potential associations between MG and:

• Increased HIV acquisition risk: Some studies suggest MG infection may increase susceptibility to HIV

• Prostate conditions: Possible links to chronic prostatitis are being explored

• Reactive arthritis: Rare cases have been reported

Psychological Impact

• The chronic nature of difficult-to-treat MG infections can have psychological effects

• Relationship stress related to STI diagnosis and partner notification

• Anxiety about potential fertility consequences

When to See a Healthcare Provider

You should consider seeking medical attention for potential Mycoplasma genitalium infection if you experience:

• Painful or frequent urination

• Unusual discharge from the penis, vagina, or rectum

• Pelvic or lower abdominal pain

• Pain during sexual intercourse

• Irregular bleeding between periods or after sex

• Symptoms that persist after treatment for other STIs

• Any genital symptoms if you've had a sexual partner diagnosed with MG

Remember that many MG infections show no symptoms, so regular STI testing is important for sexually active individuals, especially those with multiple partners.

Future Directions in Mycoplasma Genitalium Research

The scientific understanding of Mycoplasma genitalium continues to evolve, with several important areas of ongoing research:

• New treatment approaches: Development of novel antibiotics and treatment combinations to address resistance

• Rapid point-of-care tests: Creating faster, more accessible testing options

• Vaccine development: Early-stage research into potential vaccine candidates

• Global surveillance: Better tracking of prevalence and resistance patterns

• Clinical guidelines: Development of more comprehensive recommendations for testing and treatment

As our understanding improves, we can expect more standardized approaches to diagnosis and management of this increasingly important sexually transmitted infection.

Conclusion

Mycoplasma genitalium represents a significant but often overlooked sexually transmitted infection. Its capacity for asymptomatic infection, coupled with increasing antibiotic resistance, creates unique challenges for diagnosis and treatment. As awareness grows among both healthcare providers and the public, improved testing and treatment strategies will be essential for addressing this emerging public health concern.

If you're concerned about Mycoplasma genitalium or other STIs, consider comprehensive testing through our partner STDCheck, which offers discreet, accurate testing for MG and other infections. Remember that early detection and appropriate treatment are key to preventing complications and reducing transmission to partners.

This article is for informational purposes only and does not constitute medical advice. Always consult with a healthcare professional for diagnosis and treatment of medical conditions.