Optimizing treatment of antimicrobial-resistant Neisseria gonorrhoeae.

The increasing prevalence of ciprofloxacin-resistant Neisseria gonorrhoeae has required replacing inexpensive oral ciprofloxacin treatment with more expensive injectable ceftriaxone. Further, monitoring antimicrobial resistance requires culture testing, but nonculture gonorrhea tests are rapidly replacing culture. Since the strategies were similar in effectiveness (> 99%), we evaluated, from the healthcare system perspective, cost-minimizing strategies for both diagnosis (culture followed by antimicrobial susceptibility tests versus nonculture-based tests) and treatment (ciprofloxacin versus ceftriaxone) of gonorrhea in women. Our results indicate that switching from ciprofloxacin to ceftriaxone is cost-minimizing (i.e., optimal) when the prevalence of gonorrhea is > 3% and prevalence of ciprofloxacin resistance is > 5%. Similarly, culture-based testing and susceptibility surveillance are optimal when the prevalence of gonorrhea is < 13%; nonculture-based testing is optimal (cost-minimizing) when gonorrhea prevalence is > or = 13%.