Gentamicin susceptibility of Neisseria gonorrhoeae isolates from 7 provinces in China

Jing-Wei Liu,1,2 Wen-Qi Xu,1,2 Xiao-Yu Zhu,1,2 Xiu-Qin Dai,1,2 Shao-Chun Chen,1,2 Yan Han,1,2 Jun Liu,3 Xiang-Sheng Chen,1,2 Yue-Ping Yin1,21Institute of Dermatology and Hospital for Skin Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Nanjing, People’s Republic of China; 2National Center for Sexually Transmitted Diseases Control, Chinese Center for Disease Control and Prevention, Nanjing, People’s Republic of China; 3SYNAPSE Center, Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USAPurpose: Gentamicin is a promising antimicrobial for the treatment of gonorrhea. The study aimed to evaluate gentamicin minimum inhibitory concentrations (MICs) of Neisseria gonorrhoeae isolates in China.Methods: In this study, the agar dilution method was used to determine the MICs of 470 isolates collected in 2016 to four effective antimicrobials (gentamicin, azithromycin, ceftriaxone, and spectinomycin).Results: Gentamicin MICs ranged from 1 to 8 mg/L. No isolate was resistant to gentamicin. Of seven isolates simultaneously resistant to azithromycin and ceftriaxone, 6 isolates demonstrated MICs of 4 mg/L or less to gentamicin. No cross relationships were found between MICs of gentamicinand susceptibility profiles of azithromycin, ceftriaxone, and spectinomycin.Conclusion: The in vitro results suggest that gentamicin can be a promising treatment option for gonococcal infections in China. Clinical trials to evaluate the therapeutic efficacy of gentamicin are required.Keywords: Neisseria gonorrhoeae, agar dilution method, gentamicin, antimicrobial surveillance