title: Changes in the six most common sequence types of Neisseria gonorrhoeae, including ST4378, identified by surveillance of antimicrobial resistance in northern Taiwan from 2006 to 2013.
abstract: BACKGROUND
  There has been no longitudinal study of drug susceptibility in Neisseria gonorrhoeae in Taiwan since 2006.
  
  
  METHODS
  We collected 1090 gonococcal isolates from Taipei City Hospital, Taiwan from April 2006 to August 2013. We used a disk diffusion assay to determine the susceptibility to five antibiotics and an E-test to determine the minimum inhibitory concentrations for cefixime and ceftriaxone in isolates with resistance. Neisseria gonorrhoeae-multi Antigen Sequence Typing and DNA sequencing of the por and tbpB genes were used to identify sequence types.
  
  
  RESULTS
  Among the 1090 isolates, the resistances to penicillin, ciprofloxacin, cefpodoxime, cefixime, and ceftriaxone were 61.01%, 83.39%, 9.63%, 6.70%, and 2.39%, respectively. The highest minimum inhibitory concentrations of cefixime and ceftriaxone were 0.19 mg/L and 0.50 mg/L, respectively. There were 327 sequence types. The four most common sequence types in homosexuals were ST4378, ST359, ST4654, and ST547; the two most common sequence types in heterosexuals were ST421 and ST419. Each of these sequence types had more than 25 isolates. There were significant differences in the sequence types in patients with different sexual orientations (p < 0.001).
  
  
  CONCLUSIONS
  Oral cefixime or ceftriaxone injections were used as first-line drugs for the treatment of gonorrhea from 2006 to 2013 because gonorrhea isolates had low minimum inhibitory concentrations for these two drugs. The abrupt emergence of ST4378 (closely related to the notorious ST1407) since 2009 is a cause for alarm. Changes in sexual behavior, including an increase in sexual activity without the use of condoms, may have contributed to the peak in gonorrhea in 2010. Further molecular epidemiological investigations are required.
authors.affiliation: Department of Internal Medicine, Taipei City Hospital, Ren-Ai Branch, Taipei, Taiwan, ROC.
authors.forename: Ching-Wai
authors.initials: CW
authors.lastname: Cheng
authors.affiliation: Department of Laboratory Medicine, Taipei City Hospital, Kun-Ming Branch, Taipei, Taiwan, ROC.
authors.forename: Lan-Hui
authors.initials: LH
authors.lastname: Li
authors.affiliation: Division of Infectious Diseases, Department of Internal Medicine, Taipei City Hospital, Ren-Ai Branch, Taipei, Taiwan, ROC.
authors.forename: Chen-Yi
authors.initials: CY
authors.lastname: Su
authors.affiliation: Research and Diagnostic Center, Centers for Disease Control, Taipei, Taiwan, ROC.
authors.forename: Shu-Ying
authors.initials: SY
authors.lastname: Li
authors.affiliation: Division of Infectious Diseases, Department of Internal Medicine, Taipei City Hospital, Kun-Ming Branch, Taipei, Taiwan, ROC. Electronic address: myyen@tpech.gov.tw.
authors.forename: Muh-Yong
authors.initials: MY
authors.lastname: Yen
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D000942:Antigens, Bacterial / Q000235:genetics; D020682:Cefixime / Q000494:pharmacology; D015296:Ceftizoxime / Q000031:analogs & derivatives / Q000494:pharmacology; D002443:Ceftriaxone / Q000494:pharmacology; D002939:Ciprofloxacin / Q000494:pharmacology; D017280:Condoms; D024881:Drug Resistance, Bacterial / Q000235:genetics*; D005260:Female; D006069:Gonorrhea / Q000188:drug therapy / Q000453:epidemiology* / Q000382:microbiology; D006801:Humans; D008297:Male; D008826:Microbial Sensitivity Tests; D058885:Multilocus Sequence Typing; D009344:Neisseria gonorrhoeae / Q000187:drug effects* / Q000235:genetics* / Q000302:isolation & purification; D010406:Penicillins / Q000494:pharmacology; D000072339:Sexual and Gender Minorities; D013624:Taiwan / Q000453:epidemiology; D047568:Unsafe Sex; D000097623:Cefpodoxime
chemical_list: D000900:Anti-Bacterial Agents; D000942:Antigens, Bacterial; D020682:Cefixime; D015296:Ceftizoxime; D002443:Ceftriaxone; D002939:Ciprofloxacin; D010406:Penicillins; D000097623:Cefpodoxime
keywords: Neisseria gonorrhoeae-multi Antigen Sequence Typing; antimicrobial resistance; gonorrhea; homosexuals; sequence types