Antimicrobial susceptibility of Mycoplasma genitalium isolates from Pretoria, South Africa in 2012 and 2016

Background: Mycoplasma genitalium is a sexually transmitted pathogen associated with non-gonococcal urethritis and cervicitis. Azithromycin regimens have been considered first-line treatment for M. genitalium infections, with fluoroquinolone regimens effective as second-line treatments. However, the proportion of M. genitalium harbouring macrolide or fluoroquinolone resistance-associated mutations has been increasing worldwide. This study was done to compare the genotypic macrolide and fluoroquinolone resistance of M. genitalium strains obtained from women attending a termination of pregnancy clinic five years apart.Methods: M. genitalium was detected by PCR in vaginal swab samples from 100 and 104 termination of pregnancy attendees at a tertiary hospital in Pretoria, South Africa during 2012 and 2016 respectively. Genes associated with macrolide and fluoroquinolone resistance in the M. genitalium isolates were sequenced and analysed.Results: The prevalence of M. genitalium was 6.0% (6/100) in 2012 and 7.7% (8/104) in 2016. No resistance-associated mutations were seen in the 2012 isolates. Among the 2016 M. genitalium isolates, two (25%) harboured a macrolide-associated resistance mutation and one (12.5%) a fluoroquinolone resistance-associated mutation in the parC gene.Conclusions: There is an increase in macrolide and fluoroquinolone resistance among local M. genitalium strains. This highlights the need for improved surveillance.