424. Use of the ResistancePlus® MG Multiplex PCR Assay to Determine the Prevalence of Mycoplasma genitalium and Macrolide Resistance in a High-Risk US Population

BACKGROUND: Mycoplasma genitalium is a significant agent of sexually transmitted infection (STI). Cure rates have declined as rates of macrolide resistance has become increasingly prevalent. Diagnosis of M. genitalium infection and macrolide resistance detection is possible using nucleic-acid amplification tests (NAAT); use of such assays could improve patient management and antimicrobial stewardship. In this study we used one such assay, ResistancePlus MG (RPMG) to determine the prevalence of M. genitalium infection and macrolide resistance in a cohort of patients attending 3 public sexual health clinics in mid-Atlantic US states. METHODS: De-identified urogenital samples submitted to the LabCorp facility in Burlington, NC for routine Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (NG) NAAT testing from 3 public sexual health clinics were analyzed in the study. All samples had been collected in the Aptima Specimen Collection system and tested with the Aptima Combo 2 CT/NG NAAT. A total of 1,261 samples (770 male, 491 female) from this cohort were successfully tested for M. genitalium and macrolide-resistance mediating mutations (MRMM) using the RPMG multiplexed PCR assay. RESULTS: The prevalence of M. genitalium in this patient cohort was 10.4% (131/1,261), not significantly different to the prevalence of C. trachomatis (12.0%; P = 0.202) but significantly higher than the prevalence of Neisseria gonorrhoeae (6.7%; P = 0.0009). Sixty of the 131 M. genitalium positives were also positive for MRMM and thus azithromycin resistant. CONCLUSION: M. genitalium infections were common amongst unselected individuals evaluated for treatable STI in the eastern United States and the rate of macrolide resistance in this population was significant. In addition, the RPMG assay was shown to be a simple and accurate method for simultaneously diagnosing M. genitalium infections and detecting MRMM and could be used to inform therapeutic decisions. [Image: see text] DISCLOSURES: All authors: No reported disclosures.