Susceptibility of gonococcal clinical isolates to gentamicin in Guangxi region / 中华皮肤科杂志

ABSTRACT

Objective:To assess the susceptibility of gonococcal clinical isolates to gentamicin in Guangxi region, China, and to analyze the correlation between the minimum inhibitory concentration (MIC) of gentamicin and MICs of 7 other antibiotics.Methods:From December 2020 to December 2021, 584 gonococcal clinical isolates were collected from 37 medical institutions in 14 prefecture-level cities in Guangxi region. The susceptibility of gonococcal clinical isolates to ceftriaxone, cefixime, azithromycin, spectinomycin, penicillin, tetracycline, ciprofloxacin and gentamicin was determined by using an agar dilution method. The MIC values of antibiotics were logarithmically transformed with base 2, and Spearman correlation analysis was carried out to evaluate the correlation between the MIC of gentamicin and MICs of the other 7 antibiotics.Results:The MIC of gentamicin ranged from 1 to 16 mg/L, and the MIC50 and MIC90 values were 4 and 8 mg/L, respectively; 361 strains (61.8%) were fully sensitive to gentamicin with the MIC ≤ 4 mg/L, 223 strains (38.2%) moderately sensitive with the MIC ranging from 8 to 16 mg/L, and no gentamicin-resistant strains were found. The number of strains resistant to azithromycin, penicillin, tetracycline and ciprofloxacin was 136 (23.3%), 415 (71.1%), 339 (58.0%) and 574 (98.3%) respectively, the number of lowly sensitive strains to ceftriaxone and cefixime was 17 (2.9%) and 6 (1.0%) respectively, and no spectinomycin-resistant strains were found. Spearman correlation analysis showed that the MIC of gentamicin was weakly correlated with the MICs of azithromycin, spectinomycin, penicillin, tetracycline, and ciprofloxacin (all P < 0.05), but was uncorrelated with the MICs of ceftriaxone and cefixime (both P > 0.05) . Conclusion:All gonococcal clinical isolates tested in this study showed a certain degree of susceptibility to gentamicin, and cross-resistance between gentamicin and other antibiotics was less likely to occur.