Analysis on sensitivity of Neisseria gonorrhoea to cephalosporin antibiotics and multi-antigen sequence typing

Abstract

Objective To understand the molecular types of clinical isolated Neisseria gonorrhoeae (NG) in Guangzhou, and to analyze the sensitivity to the cephalosporin antibiotics. Methods A total of 121 NG strains isolated from Guangzhou Skin Disease Prevention and Control Center were included in this study. The agar dilution method was used to determine the minimum inhibitory concentrations (MIC) to ceftriaxone and cefixime. DNA was extracted for NG multi-antigen sequence typing (NG-MAST) . Results The drug-resistance analysis showed that none of the strains appeared to be resistant to ceftriaxone and cefixime. However, the low sensitivity rates were 13.2% (16/121) and 2.5% (3/121) , respectively. A total of 82 genotypes were identified among the 121 isolates. The most prevalent genotype was ST1768 (n=6) in NG strains isolated, followed by ST2083 (n=4) , ST5062 (n=4) , ST10229 (n=4) , ST1766 (n=3) , ST1866 (n=3) , and ST10339 (n=3) . There were 12 genotypes containing 2 NG strains, and 63 genotypes [76.8% (63/121) ] containing only one NG strain. Among the 13 NG strains with low sensitivity to ceftriaxone, there were 2 strains of ST10339 and 2 strains of ST10242, and the rest were single genotype. Conclusions The 121 NG strains have relatively high sensitivity to ceftriaxone and cefixime. The genotypes of these NG-MAST strains are high diversity. Key words: Neisseria gonorrhoeae; Multi-antigen sequence typing; Cephalosporins; Sensitivity