[Epidemiological and bacteriological characteristics of Neisseria gonorrhoeae isolates in China]

To investigate the antimicrobial susceptibility,auxotype, and plasmid profile of Neisseria gonorrhoeae isolates in China and to provide evidence for the development of treatment guideline and policy for control.

Agar dilution was used to detect antimicrobial susceptibility. The auxotype was determined by GC genetic medium. The plasmid was extracted by alkaline cleavage and electrophoresed.

A total of 4,976 gonococcal isolates were tested in the last 8 years. The resistant rate for penicillin was 71.60% with PPNG being 15.54%. Tetracycline-resistant (TRNG) isolates accounted for 93.02% with 10.48% high level tetracycline-resistant. The resistant rate for ciprofloxacin was also relatively high (31.78%). The resistant rates for spectinomycin and ceftriaxone were 0.36% and 0.46%. The predominant auxotypes of gonococcal isolates were proto and pro(-) during 1995 - 1996 in Nanjing, accounted for 46.4% and 47.53%, 48.4% and 50.22%, respectively. There were 8 strains harboring 4.2, 5.4, 39.5 kb plasmids and 2 harboring 4.2, 4.9, 5.4, 39.5 kb plasmids in 10 PPNG strains; 2 harboring no plasmid, 28 harboring 4.2, 4.9, 5.4, 39.5 kb plasmids in 30 non-PPNG strains. The 5.4 kb plasmid of PPNG could be digested with restriction endonuclease BamHI while the 5.4 kb plasmid of non-PPNG could not.

The gonococcal isolates were highly resistant to penicillin, tetracycline, and ciprofloxacin, while were still sensitive to spectinomycin and ceftriaxone. No significant auxotyping change was found in terms of predominant gonococcal strains in the last two years in Nanjing while 5.4 kb plasmid might be the most prevalent resistant plasmid in Nanjing.