Declining Efficacy of Moxifloxacin for Mycoplasma genitalium Infection: Time for Fluoroquinolone Resistance–Guided Therapy?

Abstract

Background: We assessed trends in moxifloxacin use and efficacy for Mycoplasma genitalium over a decade at Melbourne Sexual Health Centre (MSHC). Specific M. genitalium mutations, namely ParC-S83I, have been associated with moxifloxacin failure. In 2024 MSHC introduced ParC-S83 testing, recommending moxifloxacin for ParC-S83 wild type infections and alternative regimens if the ParC-S83I mutation was detected. We present preliminary impacts of ParC-S83 testing on moxifloxacin use and efficacy. Methods: Clients with M. genitalium from 2015 to 2024 were treated with doxycycline preceding macrolide resistance–guided azithromycin or moxifloxacin. Clients with a test of cure 14–90 days after compl..