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 continuing to increase. In this study, we examined the levels of antibiotic 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. 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, compared to North Queensland and this was consistent in both males and females ( P = 0.007). Rectal 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 for quinolones in females from North Queensland (1.6%). These data highlight the high levels of antibiotic resistance in M. genitalium within Queensland and the challenges faced by STI clinicians in managing these infections. The data do however show that 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.