What is the recommended treatment for Mycoplasma genitalium infections?

Treatment of Mycoplasma genitalium Infections

For Mycoplasma genitalium infections, the recommended first-line treatment is azithromycin 500 mg on day one, followed by 250 mg on days 2-5, which has a cure rate of 95-99% for macrolide-susceptible infections. 1

Treatment Algorithm

First-line Treatment

• For macrolide-susceptible M. genitalium or when resistance testing is unavailable:
  • Azithromycin 500 mg on day one, followed by 250 mg on days 2-5 (oral) 1, 2
  • Alternative: Azithromycin 1 g orally in a single dose (though this has a higher risk of developing resistance) 1

Second-line Treatment (for macrolide-resistant infections)

• Moxifloxacin 400 mg once daily for 7 days 1, 2
  • Note: Cure rate with moxifloxacin is approximately 92% 1
  • The efficacy of moxifloxacin has decreased from 100% to 89% since 2010 due to increasing resistance 3

Third-line Treatment (for persistent infection after azithromycin and moxifloxacin)

• Doxycycline 100 mg twice daily for 14 days (may cure 30-40%) 4, 2
• Pristinamycin 1 g four times daily for 10 days (cure rate ~75-90%) 4, 2

For Complicated Infections (PID, epididymitis)

• Moxifloxacin 400 mg once daily for 14 days 4, 2

Resistance Testing

• If available, nucleic acid amplification testing (NAAT) diagnosis should be followed with an assay for macrolide resistance to guide therapy 1, 2
• Resistance-guided therapy has shown high efficacy (>92%) in treating M. genitalium infections 5

Management of Sexual Partners

• Sexual partners should receive the same treatment regimen as the index case 1
• Both patients and partners should abstain from sexual intercourse until:
  • 7 days after single-dose therapy, OR
  • Until completion of multi-day regimens AND resolution of symptoms 1

Test of Cure

• A test of cure is recommended 2-4 weeks after completing treatment 1
• This is particularly important given the rising rates of antimicrobial resistance

Clinical Pearls and Pitfalls

Important Considerations

• Persistent M. genitalium infection after treatment is strongly associated with persistent symptoms (91% vs 17% in eradicated infections) 6
• Pre-treatment with doxycycline before azithromycin may decrease organism load and reduce the risk of macrolide resistance selection 2, 5

Antimicrobial Stewardship

• Moxifloxacin should be reserved for confirmed M. genitalium infections that have failed first-line therapy 1
• Indiscriminate use of moxifloxacin could accelerate fluoroquinolone resistance development 1, 3
• The prevalence of ParC mutations (associated with quinolone resistance) is approximately 22% in macrolide-resistant cases 5

Monitoring for Treatment Failure

• Patients with persistent symptoms after treatment should be re-evaluated and re-tested for M. genitalium 1
• De novo macrolide resistance can develop in approximately 4.6% of cases treated with azithromycin 5

By following this treatment algorithm and considering antimicrobial resistance patterns, clinicians can optimize outcomes for patients with M. genitalium infections while practicing good antimicrobial stewardship.