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Objectives: Antimicrobial resistance (AMR) in Neisseria gonorrhoeae is a major public health concern worldwide. This is the first nationwide study, performed within the China Gonococcal Antimicrobial Susceptibility Programme (China-GASP), regarding AMR, including ceftriaxone genetic resistance determinants, and molecular epidemiology of gonococci in China.Methods: Gonococcal isolates (n = 1257) from consecutive patients were collected at 11 sentinel sites distributed across China during 2012-13. Susceptibility to ceftriaxone, spectinomycin, ciprofloxacin and tetracycline was determined using the agar dilution method. Ceftriaxone resistance determinants penA and penB were examined using sequencing. N. gonorrhoeae multiantigen sequence typing (NG-MAST) was performed for molecular epidemiology.Results: Among isolates, 0.2% were resistant to spectinomycin, 4.4% to ceftriaxone, 42.9% to tetracyclines (high-level resistance) and 99.8% to ciprofloxacin. Among 890 sequenced isolates, 16 (1.8%) possessed a penA mosaic allele; 4 of these isolates belonged to the MDR internationally spread NG-MAST genogroup G1407 (first description in China). Non-mosaic penA alleles with an A501T mutation and an A102D alteration in porB1b were statistically associated with decreased susceptibility/resistance to ceftriaxone. NG-MAST G10339, G1424 and G1053 were associated with decreased susceptibility/resistance to ceftriaxone.Conclusions: In China, ceftriaxone and spectinomycin can continue to be recommended for gonorrhoea treatment, with the possible exception of Hainan and Sichuan provinces where ceftriaxone resistance exceeded 5% and AMR surveillance needs to be strengthened. Molecular approaches including genotyping and AMR determinant analysis can be valuable to supplement and enhance conventional surveillance of gonococcal AMR in China. [ABSTRACT FROM AUTHOR]

Objectives Antimicrobial resistance (AMR) in Neisseria gonorrhoeae is a major problem worldwide. This study investigated the AMR, genetic ceftriaxone resistance determinants and molecular epidemiology of N. gonorrhoeae in Nanjing, China. Methods N. gonorrhoeae isolates were collected in 2007 (n = 198) and 2012 (n = 80). The susceptibility to ceftriaxone, spectinomycin, ciprofloxacin and tetracycline was determined using an agar-dilution method. The ceftriaxone resistance determinants penA, mtrR and penB were examined using sequencing. N. gonorrhoeae multi-antigen sequence typing (NG-MAST) was performed for molecular epidemiology. Results All isolates were resistant to ciprofloxacin, 42.4% produced β-lactamase and 34.9% showed high-level resistance to tetracycline (MIC ≥16 mg/L). In total, 5.4% of isolates were resistant to ceftriaxone; however, all of these isolates were obtained in 2007 and the susceptibility to ceftriaxone appeared to have increased. All isolates were susceptible to spectinomycin. No penA mosaic alleles were found. Non-mosaic penA alleles with A501T and G542S alterations, an H105Y alteration in mtrR and an A102D/N alteration in porB1b were statistically associated with decreased susceptibility or resistance to ceftriaxone. The most prevalent NG-MAST sequence types (STs) were ST568 (n = 13), ST270 (n = 9) and ST421 (n = 7). ST270 was the most common ST in isolates with decreased susceptibility or resistance to ceftriaxone. Conclusions Ceftriaxone, ideally 500 mg and together with azithromycin (1–2 g), should be recommended for treatment of gonorrhoea in Nanjing, China. However, N. gonorrhoeae strains with resistance to ceftriaxone have been found in Nanjing. NG-MAST and ceftriaxone resistance determinant analysis can be valuable to supplement the antimicrobial resistance surveillance in China, which needs to be further strengthened. [ABSTRACT FROM PUBLISHER]