Resistance of Neisseria gonorrhoeae epidemic strains to antibiotics: report of resistant isolates and surveillance in Zhanjiang, China: 1998 to 1999

BACKGROUND: Antibiotics are widely used to treat gonorrhea. Changes in the susceptibility of Neisseria gonorrhoeae to these agents may influence their use. GOAL: To measure the antibiotic susceptibility of N gonorrhoeae epidemic strains in Zhanjiang (Guangdong) and to evaluate the prevalence of strains with reduced susceptibility. STUDY DESIGN: A total of 98 gonococcal isolates obtained from 1998 through 1999 in Zhanjiang were tested for antibiotic susceptibility based on the systemic identification. The inhibitory zone diameters (mm) and the MICs of penicillin, tetracycline, spectinomycin, ceftriaxone, and ciprofloxacin were determined using disk-diffusion and agar-dilution methods, respectively. The susceptibilities of these isolates were defined using criteria of the National Committee for Clinical Laboratory Standards. RESULTS: The percentages of gonococci-resistant strains to penicillin, tetracycline, spectinomycin, ceftriaxone, and ciprofloxacin were 32.65%, 69.39%, 8.16%, 13.27%, 82.65% by disk-diffusion method and 23.91%, 49.46 %, 11.11%, 16.48%, 59.34% by agar-dilution method, respectively. CONCLUSIONS: The resistant strains of contemporary gonococci in Zhanjiang were serious, especially for ciprofloxacin resistance. Continued active surveillance is needed to detect and control the spread of ceftriaxone-resistant and spectinomycin-resistant N gonorrhoeae.