Background and objective: The appearance and the endemic of penicillinase-producing Neisseria gonorrhoeae (PPNG) and other resistant strains cause much difficulty in the treatment of gonorrhea. To keep surveillance of the strains is important for the control of gonorrhea nationwide.
Goal of this study: To know the resistance to antibiotics of Neisseria gonorrhoeae strains isolated in China.
Study design: The minimum inhibitory concentration (MIC) to penicillin, spectinomycin, and cephalosporins was determined by the agar plate dilution test in strains of N. gonorrhoeae submitted from six cities in various areas of the country during the period 1987-1992, and the prevalence of penicillinase-producing N. gonorrhoeae strains were examined by the rapid idometric method.
Results: The resistant strains to penicillin (MIC > or = 1.0 microgram/ml) accounted for 57.5% of all isolates. The resistant strains to spectinomycin (MIC > or = 128 micrograms/ml) made up 1.3% and the strains which had a MIC closing resistance (MIC = 64 micrograms/ml) accounted for 4%. There were 18 PPNG strains (4.3%) in 419 isolates from Nanjing and Nanning city. The resistant strains to ceftrixone and cefotaxime accounted for 2.6% and 4.2%, respectively.
Conclusion: The situation of N. gonorrhoeae resistance to penicillin is rather serious in the country and relevant measures should be taken in the choice of therapeutic drugs, the follow-up of patients and the surveillance of gonorrhea.
PIP: In China, staff at the National Center for STD Control and Research in Nanjing conducts surveillance of Neisseria gonorrhoeae to identify antibiotic-resistant strains, so health officials can control gonorrhea. Between 1987 and 1992, the center isolated 1529 strains from patients of clinics in the cities of Nanjing, Nanning, Harbin, Dalian, Shanghai, and Urumqi. Laboratory staff used the agar plate dilution test in the strains to determine the minimum inhibitory concentration (MIC) to penicillin, spectinomycin, and cephalosporins. They used the rapid idiometric method to examine the prevalence of penicillinase-producing N. gonorrhoeae (PPNG) strains. Most strains (57.5%) had MICs of = or 1 mcg/ml penicillin. The MIC50 values for penicillin increased each year (0.47, 0.45, 0.56, 0.79, 0.79, and 0.89 mcg/ml). PPNG strains comprised 18 (4.3%) of 419 strains isolated from Nanjing and Nanning. Resistant strains to spectinomycin (MIC 128 mcg/ml and the critical MIC values of 64 mcg/ml) made up 1.3% and 4% of all isolates, respectively. Few strains were resistant to ceftriaxone and cefotaxime (MIC = or 1 mcg/ml; 2.6% and 4.2%, respectively). These findings show considerable N. gonorrhoeae resistance to penicillin in China. They also demonstrate a need to adopt appropriate measures in the choice of drugs, follow-up of patients, and the surveillance of gonorrhea.