Antimicrobial resistance in Neisseria gonorrhoeae isolates at the Bangrak STIs Center, Bangkok, Thailand and whole-genome sequencing of antimicrobial-resistant isolates, 2018-23
Objectives: Antimicrobial resistance (AMR) in Neisseria gonorrhoeae has become a global public health concern, particularly with the increasing resistance to ceftriaxone, the last remaining treatment option, in several Asian countries. We examined the AMR in N. gonorrhoeae isolates obtained at the Bangrak STIs Center, Bangkok, Thailand in 2018-2023, and whole-genome sequenced isolates resistant to ceftriaxone, cefixime and/or azithromycin.  Methods: Genital and extragenital swabs from males, females and transgender women were cultured. Etest for five antimicrobials and EUCAST breakpoints (v15.0), where available, were used to determine AMR. Susceptibility to ciprofloxacin was measured by disc diffusion method. AMR isolates were whole-genome sequenced using Illumina NextSeq 550.  Results: In 2018-23, 765 gonococcal isolates from 739 patients were cultured. The resistance to ceftriaxone, cefixime, azithromycin, tetracycline, and ciprofloxacin was 0.5%, 0.8%, 1.7%, 83.7%, and 95.7%, respectively. MICs of gentamicin were ranging from 1 to 16 mg/L. Ceftriaxone-resistant isolates (n=3, 1.2%), all resistant also to cefixime, were firstly detected in 2023. Two (1.4%) additional cefixime-resistant isolates were found in 2022. Azithromycin-resistant isolates (n=1, 0.9%) firstly emerged in 2020 and increased to nine (3.7%) cases in 2023. All ceftriaxone-resistant isolates contained penA-60.001, but cefixime resistance was additionally caused by penA-34.019 and penA-10.001.  Conclusions: Resistance to ceftriaxone, cefixime, and azithromycin in gonococcal isolates obtained at the Bangrak STIs Center, Bangkok, Thailand has emerged and appears to be increasing. The emergence of strains resistant to these last remaining treatment options strongly emphasize the need for strengthened national culture-based and genomic surveillance to prevent the spread of MDR and XDR N. gonorrhoeae in Thailand and globally.
Objectives: Antimicrobial resistance (AMR) in Neisseria gonorrhoeae has become a global public health concern, particularly with the increasing resistance to ceftriaxone, the last remaining treatment option, in several Asian countries. We examined the AMR in N. gonorrhoeae isolates obtained at the Bangrak STIs Center, Bangkok, Thailand in 2018-2023, and whole-genome sequenced isolates resistant to ceftriaxone, cefixime and/or azithromycin.  Methods: Genital and extragenital swabs from males, females and transgender women were cultured. Etest for five antimicrobials and EUCAST breakpoints (v15.0), where available, were used to determine AMR. Susceptibility to ciprofloxacin was measured by disc diffusion method. AMR isolates were whole-genome sequenced using Illumina NextSeq 550.  Results: In 2018-23, 765 gonococcal isolates from 739 patients were cultured. The resistance to ceftriaxone, cefixime, azithromycin, tetracycline, and ciprofloxacin was 0.5%, 0.8%, 1.7%, 83.7%, and 95.7%, respectively. MICs of gentamicin were ranging from 1 to 16 mg/L. Ceftriaxone-resistant isolates (n=3, 1.2%), all resistant also to cefixime, were firstly detected in 2023. Two (1.4%) additional cefixime-resistant isolates were found in 2022. Azithromycin-resistant isolates (n=1, 0.9%) firstly emerged in 2020 and increased to nine (3.7%) cases in 2023. All ceftriaxone-resistant isolates contained penA-60.001, but cefixime resistance was additionally caused by penA-34.019 and penA-10.001.  Conclusions: Resistance to ceftriaxone, cefixime, and azithromycin in gonococcal isolates obtained at the Bangrak STIs Center, Bangkok, Thailand has emerged and appears to be increasing. The emergence of strains resistant to these last remaining treatment options strongly emphasize the need for strengthened national culture-based and genomic surveillance to prevent the spread of MDR and XDR N. gonorrhoeae in Thailand and globally.