In men, infection with Mgen can cause symptomatic and asymptomatic urethritis. In women, Mgen infection can double the risk of cervicitis, pelvic inflammatory disease (PID), preterm delivery, infertility and more. It is also associated with an increased risk of acquiring HIV or nongonococcal urethritis.2-4 Unfortunately, many people with Mgen will not be aware they have it. Most cases are asymptomatic, and any associated symptoms are similar to those caused by other STIs like chlamydia.
Those most at risk for Mgen infection include those who engage in unprotected vaginal or anal sex, engage in high-risk sexual behavior, have sexual contact with individuals diagnosed with an STI or PID, or have contact with individuals infected with Mgen.2,5
Is an extremely slow-growing organism²
Causes symptomatic and asymptomatic urethritis among men²
Frequently causes asymptomatic infections among women²
Is often the sole pathogen; however, infection with C. trachomatis is common in selected geographic areas
Is more common among people ages 15 to 24 years than in people ages 35 to 39 years³
Can be difficult to treat due to rapidly rising incidence of macrolide resistance²
The presence of Mgen is associated with an increased risk of acquiring HIV2-4
Resistance to azithromycin has been rapidly increasing and has been confirmed in multiple studies. Prevalence of molecular markers for macrolide resistance, which highly correlates with treatment failure, ranges from 44% to 90% in the United States.6,7 This complicates the treatment of Mgen infection by empiric antibiotic regimens.
Clinical treatment failure and high-level in vitro macrolide resistance have been linked with mutations in the 23S rRNA gene of M. genitalium.
Macrolide resistance mediating mutations have been observed in 20-80% of cases.7,8
Two-stage therapy approaches, ideally using resistance-guided therapy, are recommended for treatment. Resistance-guided therapy has demonstrated cure rates of >90% and should be used whenever possible; however, it requires access to macrolide-resistance testing.2
Mgen can be difficult to detect because the bacterial organism load is low compared to other STIs commonly tested for. This means that a highly sensitive rRNA test is needed for accurate diagnosis.9
Mgen is a slow-growing organism, so nucleic acid amplification testing (NAAT) is the only viable diagnostic solution and is recommended by the CDC.2
Guidelines for Mgen infections now recommend testing for macrolide resistance to help determine appropriate treatment.11,12,13
When applying resistance-guided therapy to a population with high levels of antibiotic resistance and cure rates below 67%, patient outcome was significantly improved.12
Cure rates in the Mgen macrolide-susceptible population exceeded 94%. Using doxycycline for initial STI treatment reduces overall use of azithromycin and reduces initial bacterial load which may improve subsequent Mgen treatment.7
With increasing antibiotic resistance, there is a need to detect mutations conferring macrolide resistance when they are present.
Mgen treatment failures can occur when using doxycycline, azithromycin and moxifloxacin. Microbiologic cure rates are poor with either doxycycline or azithromycin monotherapy (~50% or less). Microbiologic cure rates for moxifloxacin were initially high (close to 100%) but have declined to 89% in studies conducted from 2010-2017.10
Labcorp's mycoplasma genitalium assay is now available for the diagnosis of Mgen with a reflex to macrolide resistance.
| Number | Name |
|---|---|
| 180092 | Mycoplasma genitalium, NAA, Swab With Reflex to Macrolide Resistance Testing |
| 180084 | Mycoplasma genitalium, NAA, Urine With Reflex to Macrolide Resistance Testing |
