Evaluation of the Allplex NG & DR assay for molecular prediction of ciprofloxacin and azithromycin resistance in Neisseria gonorrhoeae.

PURPOSE

Molecular methods to detect antimicrobial resistance in Neisseria gonorrhoeae (Ng) are increasingly needed worldwide to improve diagnostic tests and enable individualized patient treatments. The Allplex™ NG & DR Assay (NG & DR assay) was assessed for its ability to detect Ng and its antimicrobial resistance. The assay predicts ciprofloxacin resistance and susceptibility by targeting the molecular antimicrobial resistance (AMR) determinant gyrA S91F. The AMR determinants 23 S rRNA A2059G and C2611T were investigated to predict azithromycin wild-type and nonwild-type genotypes.

METHODS

After antimicrobial susceptibility testing, 153 Ng isolates were evaluated with the NG & DR assay. Furthermore, 394 clinal specimens, including 76 with corresponding antimicrobial susceptibility results, were analyzed simultaneously by the NG & DR assay and the in-house SYBR-Green assay.

RESULTS

The NG & DR assay predicted ciprofloxacin resistance and susceptibility with a sensitivity and specificity of 98.2% and 100.0%, respectively, and the results were consistent with those of the SYBR-Green assay for the detection of S91F. For the prediction of azithromycin nonwild-type and wild-type genotypes, the NG & DR assay demonstrated a sensitivity and specificity of 50.0% and 100.0%, respectively.

CONCLUSION

The NG & DR assay demonstrated promising results for the molecular prediction of ciprofloxacin resistance and susceptibility, expanding the potential diagnostic tool kit for individualized patient treatment. Furthermore, it might serve as a surveillance tool for azithromycin nonwild-type strains.