Remarkable increase in fluoroquinolone-resistant Mycoplasma genitalium in Japan

J Antimicrob Chemother. 2014 Sep;69(9):2376-82. doi: 10.1093/jac/dku164. Epub 2014 Jun 2.


Objectives: We determined the prevalence of macrolide and fluoroquinolone resistance-associated mutations in Mycoplasma genitalium DNA specimens from men with non-gonococcal urethritis (NGU) and analysed their effects on antibiotic treatments of M. genitalium infections.

Methods: In this retrospective study, we examined antibiotic resistance-associated mutations in the 23S rRNA, gyrA and parC genes of M. genitalium and the association of the mutations with microbiological outcomes of antibiotic treatments in men with M. genitalium-positive NGU.

Results: No macrolide resistance-associated mutations in the 23S rRNA gene were observed in 27 M. genitalium DNA specimens in 2011 and in 24 in 2012. However, 5 of 17 in 2013 had 23S rRNA mutations. Three of 15 in 2011, 6 of 19 in 2012 and 8 of 17 in 2013 had fluoroquinolone resistance-associated alterations in ParC. Three in 2013 had both the antibiotic resistance-associated alterations coincidentally. In two men with M. genitalium harbouring 23S rRNA mutations, the mycoplasma persisted after treatment with a regimen of 2 g of extended-release azithromycin (AZM-SR) once daily for 1 day. All nine men with mycoplasma harbouring ParC alterations were microbiologically cured with a regimen of 100 mg of sitafloxacin twice daily for 7 days.

Conclusions: Macrolide- or fluoroquinolone-resistant M. genitalium appears to be increasing, and the increase in fluoroquinolone-resistant mycoplasmas is especially remarkable in Japan. Mycoplasmas harbouring 23S rRNA mutations would be resistant to the AZM-SR regimen, but those harbouring ParC alterations would still be susceptible to the sitafloxacin regimen.

Keywords: 23S rRNA; GyrA; ParC; azithromycin; sitafloxacin.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Anti-Bacterial Agents / pharmacology*
  • Anti-Bacterial Agents / therapeutic use
  • DNA Gyrase / genetics
  • DNA Topoisomerase IV / genetics
  • DNA, Bacterial / chemistry
  • DNA, Bacterial / genetics
  • DNA, Ribosomal / chemistry
  • DNA, Ribosomal / genetics
  • Drug Resistance, Bacterial*
  • Fluoroquinolones / pharmacology*
  • Fluoroquinolones / therapeutic use
  • Humans
  • Japan / epidemiology
  • Macrolides / pharmacology
  • Macrolides / therapeutic use
  • Male
  • Molecular Sequence Data
  • Mutation*
  • Mycoplasma Infections / epidemiology*
  • Mycoplasma Infections / microbiology
  • Mycoplasma genitalium / drug effects*
  • Mycoplasma genitalium / isolation & purification
  • Prevalence
  • RNA, Ribosomal, 23S / genetics
  • Retrospective Studies
  • Sequence Analysis, DNA
  • Treatment Outcome


  • Anti-Bacterial Agents
  • DNA, Bacterial
  • DNA, Ribosomal
  • Fluoroquinolones
  • Macrolides
  • RNA, Ribosomal, 23S
  • DNA Topoisomerase IV
  • DNA Gyrase

Associated data

  • GENBANK/AB919117
  • GENBANK/AB919118
  • GENBANK/AB919119
  • GENBANK/AB919120
  • GENBANK/AB919121