Evaluation of the molecular detection of ciprofloxacin resistance in Neisseria gonorrhoeae by the ResistancePlus GC assay (SpeeDx)

Diagn Microbiol Infect Dis. 2021 Apr;99(4):115262. doi: 10.1016/j.diagmicrobio.2020.115262. Epub 2020 Nov 12.

Abstract

There is growing concern due to the emergence of multidrug resistance in Neisseria gonorrhoeae. A rapid molecular test which guides and provides antimicrobial susceptibility knowledge prior to start of treatment is needed. This study evaluated the clinical performance of the ResistancePlus GC assay compared to in-house PCR and antimicrobial susceptibility results for ciprofloxacin resistance. Samples were selected from a range of sites with corresponding cultures isolated from the same patient episode. The ResistancePlus GC assay displayed high sensitivity for N. gonorrhoeae detection (98.5%) and gyrA detection (97.1%). There was high agreement (98.9%) between the ResistancePlus GC assay and culture phenotype. Mixed population testing showed that the assay was able to detect resistance in a sample containing a minority variant of 27% resistant. The ResistancePlus GC assay performed well and could be used to provide a clinically relevant indication of ciprofloxacin susceptibility for the treatment of gonorrhoea.

Keywords: Ciprofloxacin; Neisseria gonorrhoeae; Resistance; ResistancePlus GC.

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • Anti-Bacterial Agents / pharmacology*
  • Bacteriological Techniques*
  • Ciprofloxacin / pharmacology*
  • Drug Resistance, Bacterial*
  • Female
  • Gonorrhea / drug therapy
  • Gonorrhea / microbiology
  • Humans
  • Male
  • Microbial Sensitivity Tests
  • Middle Aged
  • Neisseria gonorrhoeae / drug effects*
  • Young Adult

Substances

  • Anti-Bacterial Agents
  • Ciprofloxacin