The emergence of Neisseria gonorrhoeae with decreased susceptibility to Azithromycin in Kansas City, Missouri, 1999 to 2000

Sex Transm Dis. 2004 Feb;31(2):73-8. doi: 10.1097/01.OLQ.0000109514.91508.FC.


Background and objectives: We describe the first cluster of persons with Neisseria gonorrhoeae with decreased susceptibility to azithromycin (AziDS; minimum inhibitory concentration >/=1.0 microg/mL) in the United States. GOAL The goal of this study was to identify risk factors for AziDS N. gonorrhoeae and to describe isolate microbiology.

Study design: Persons with AziDS N. gonorrhoeae (cases) were identified in Kansas City, Missouri, through the Gonococcal Isolate Surveillance Project (GISP) in 1999 and expanded surveillance, January 2000 to June 2001. A case-control study using 1999 GISP participants was conducted; control subjects had azithromycin-susceptible N. gonorrhoeae.

Results: Thirty-three persons with AziDS N. gonorrhoeae were identified. Case patients were older than control patients (median age, 33 years vs. 23 years; P <0.001). Fifty percent of cases and 13% of control subjects had a history of sex with a female commercial sex worker (odds ratio, 7.0; 95% confidence interval, 1.3-36.0); 50% of cases and 4% of control subjects met sex partners on street A (P <0.01). AziDS N. gonorrhoeae isolates were phenotypically and genotypically similar and contained an mtrR gene mutation.

Conclusions: With few treatment options remaining, surveillance for antimicrobial-resistant N. gonorrhoeae is increasingly important, especially among persons at high risk.

MeSH terms

  • Adolescent
  • Adult
  • Anti-Bacterial Agents / pharmacology*
  • Azithromycin / pharmacology*
  • Case-Control Studies
  • Communicable Diseases, Emerging / epidemiology
  • Communicable Diseases, Emerging / microbiology
  • Drug Resistance, Bacterial*
  • Female
  • Gonorrhea / epidemiology*
  • Gonorrhea / microbiology*
  • Humans
  • Male
  • Microbial Sensitivity Tests
  • Middle Aged
  • Missouri / epidemiology
  • Neisseria gonorrhoeae / drug effects*
  • Neisseria gonorrhoeae / isolation & purification
  • Risk Factors
  • Risk-Taking


  • Anti-Bacterial Agents
  • Azithromycin