Molecular Determination of Mutations associated with Antimicrobial Resistance using Gonorrhea-positive nucleic acid amplification test specimens (NAATs)<<Return to Laboratory
Molecular determination of mutations associated with antimicrobial resistance by PCR and the AMR prediction of cephalosporins, ciprofloxacin and azithromycin.
Gonorrhoea positive specimens in APTIMA or Roche Cobas buffer, including urine, urethral/urogenital swabs, vaginal swabs, and rectal swabs, or DNA extracts. Neat urine and pharyngeal swabs are not recommended. Other specimen types may be accepted with proper rationale for testing or by prior approval from the Streptococcus and STI Unit. The minimum required volume is 1mL. Submit only one GC NAAT per case unless related to a treatment failure investigation.
Store samples refrigerated or frozen until shipped for testing. Ship frozen samples on dry ice and refrigerated samples on cold packs.
Shipping of specimens shall be done by a TDG certified individual in accordance with TDG regulations. For additional information regarding classification of specimens for the purposes of shipping, consult either Part 2 Appendix 3 of the TDG Regulations or section 3.6.2 of the IATA Dangerous Goods Regulations as applicable.
Infection with N. gonorrhoeae.
Completed NML GC NAAT requisition form with sender lab name, address, telephone number and emails address. All patient information must be filled out including patient identified (specimen reference #), date of birth and sex, testing platform, date collected, isolation site and test requested. Urgent specimens must be stated as such on the requisition. The lab should be informed of urgent samples prior to receiving them.
DNA from all gonorrheal samples received at the NML for PCR testing is initially extracted using a commercially-available kit. Single Nucleotide Polymorphism (SNP) qPCR assays are used to predict antimicrobial resistance (AMR) to cephalosporins (ponA, mtrR delA, porB, penA A311V, penA A501, penA N513Y, penA G545S), ciprofloxacin (gyrA S91 and parC), and azithromycin (23S 2059, 23S 2611 and mtrR AZR) (1). Sample is also tested for porA to confirm N. gonorrhoeae identification and ensure DNA extraction was successful. Results are for surveillance purposes only.
- Peterson SW, Martin I, Demczuk W, Barairo N, Naidu P, Lefebvre B, Allen V, Hoang L, Hatchette TF, Alexander D, Tomas K, Trubnikov M, Wong T, Mulvey MR. Multiplex real-time PCR assays for the prediction of cephalosporin, ciprofloxacin and azithromycin antimicrobial susceptibility of positive Neisseria gonorrhoeae nucleic acid amplification test samples. J Antimicro Chemo. 2020; 75: 3485-3490.