Characteristics of Mycoplasma genitalium Urogenital Infections in a Diverse Patient Sample from the United States: Results from the Aptima Mycoplasma genitalium Evaluation Study (AMES)

Data from a large prospective multicenter clinical validation study of a nucleic acid amplification in vitro diagnostic test for Mycoplasma genitalium were analyzed to describe the prevalence of M. genitalium infection, risk factors, and disease associations in female and male patients seeking care in diverse geographic regions of the United States. Among 1,737 female and 1,563 male participants, the overall prevalence of M. genitalium infection was 10.3% and was significantly higher in persons ages 15 to 24 years than in persons ages 35 to 39 years (for females, 19.8% versus 4.7% [odds ratio {OR} = 5.05; 95% confidence interval {CI} = 3.01 to 8.46]; for males, 16.5% versus 9.4% [OR = 1.91; 95% CI = 1.20 to 3.02]). The risk for M. genitalium infection was higher in black than in white participants (for females, 12.0% versus 6.8% [OR = 1.88; 95% CI = 1.30 to 2.72]; for males, 12.9% versus 6.9% [OR = 2.02; 95% CI = 1.38 to 2.96]) and higher in non-Hispanic than in Hispanic participants (for females, 11.2% versus 6.0% [OR = 1.97; 95% CI = 1.25 to 3.10]; for males, 11.6% versus 6.8% [OR = 1.80; 95% CI = 1.14 to 2.85]). Participants reporting urogenital symptoms had a significantly elevated risk of M. genitalium infection compared to that for asymptomatic individuals (for females, OR = 1.53 [95% CI = 1.09 to 2.14]; for males, OR = 1.42 [95% CI = 1.02 to 1.99]). Women diagnosed with vaginitis and cervicitis had a higher prevalence of M. genitalium infection than women without those diagnoses, although this was statistically significant only for vaginitis (for vaginitis, OR = 1.88 [95% CI = 1.37 to 2.58]; for cervicitis, OR = 1.42 [95% CI = 0.61 to 2.96]). A diagnosis of urethritis in men was also significantly associated with M. genitalium infection (OR = 2.97; 95% CI = 2.14 to 4.13). Few characteristics distinguished asymptomatic from symptomatic M. genitalium infections. These results from persons seeking care in the United States suggest that M. genitalium infection should be considered in young persons presenting with urogenital symptoms.

Evaluation of the ResistancePlus MG FleXible Assay for Detection of Wild-Type and 23S rRNA-Mutated Mycoplasma genitalium Strains

Antibiotic resistance in Mycoplasma genitalium is rising globally, and resistance-guided diagnostics can facilitate targeted and timely treatment. The ResistancePlus MG FleXible (RPMG Flex) assay for the detection of M. genitalium and macrolide resistance-mediating mutations (MRMM) was evaluated for analytical sensitivity, specificity, reproducibility, and inhibition in the presence of interfering substances by simulating M. genitalium-negative pooled urine and swab matrices with M. genitalium cultures. Furthermore, the clinical sensitivity of the assay was evaluated and compared with a reference real-time PCR assay. The analytical sensitivity of the RPMG Flex assay was 157 genomes/ml for wild-type (WT) and 387 genomes/ml for MRMM strains in both matrices. For clinical specimens, the RPMG assay had an overall sensitivity of 96.1% (95% urine: 10/10 WT, 9/10 MRMM; 96.5% swab: 25/26 WT, 26/29 MRMM) compared to 85.7% for the MgPa/MagNAPure24 assay (95% urine: 19/20; 87% swab: 48/57). Clinical specificity was 100% for urine and 98.5% for swab specimens, respectively. No inhibition due to the presence of any of the tested interfering substances was observed. The RPMG Flex assay was more sensitive than the reference MgPa assay, in particular, for swab specimens. The implementation of this assay may increase ease of use and considerably decrease hands-on time for sample preparation compared to a standard block-based assay. The RPMG Flex assay for the GeneXpert Dx system provides a much-needed platform for the simultaneous detection of MG and MRMM and may thereby facilitate resistance-guided therapy for M. genitalium infections.

Levels of Mycoplasma genitalium Antimicrobial Resistance Differ by Both Region and Gender in the State of Queensland, Australia: Implications for Treatment Guidelines

Mycoplasma genitalium is frequently associated with urogenital and rectal infections, with the number of cases of macrolide-resistant and quinolone-resistant M. genitalium infection continuing to increase. In this study, we examined the levels of resistance to these two common antibiotic treatments in geographically distinct locations in Queensland, Australia. Samples were screened for macrolide resistance-associated mutations using a commercially available kit (ResistancePlus MG; SpeeDx), and quinolone resistance-associated mutations were identified by PCR and DNA sequencing. Comparisons between antibiotic resistance mutations and location/gender were performed. The levels of M. genitalium macrolide resistance were high across both locations (62%). Quinolone resistance mutations were found in ∼10% of all samples, with a number of samples harboring mutations conferring resistance to both macrolides and quinolones. Quinolone resistance was higher in southeast Queensland than in north Queensland, and this was consistent in both males and females (P = 0.007). The M. genitalium isolates in rectal swab samples from males harbored high levels of macrolide (75.9%) and quinolone (19%) resistance, with 15.5% harboring resistance to both classes of antibiotics. Overall, the lowest observed level of resistance was to quinolones in females from north Queensland (1.6%). These data highlight the high levels of antibiotic resistance in M. genitalium isolates within Queensland and the challenges faced by sexually transmitted infection clinicians in managing these infections. The data do, however, show that the levels of antibiotic resistance may differ between populations within the same state, which has implications for clinical management and treatment guidelines. These findings also support the need for ongoing antibiotic resistance surveillance and tailored treatment.