Cefixime for the Treatment of Neisseria gonorrhoeae Infections in a Setting With Increased Antimicrobial Resistance: A Retrospective Study in Hanoi, Vietnam.

BACKGROUND

Antimicrobial resistance in Neisseria gonorrhoeae is a global health problem. Ceftriaxone is the first-line treatment, while cefixime is recommended as an alternative. Data on cefixime treatment outcomes, particularly from areas with increased resistance, are limited.

METHODS

We conducted a retrospective review of all gonococcal infections treated with cefixime 800 mg and ceftriaxone 500 mg within a sexual health program in Hanoi, Vietnam, between May 2022 and February 2023. Gonococcal infections were detected via culture or N. gonorrhoeae nucleic acid amplification testing (NAAT) at pharyngeal, rectal, or urogenital sites. A test of cure (TOC) was done 10-21 days posttreatment. Multivariate logistic regression was used to evaluate factors associated with TOC positivity.

RESULTS

There were 24 participants treated with cefixime and 75 participants treated with ceftriaxone. The median time to follow-up testing was 12 days (range, 8-18 days) for cefixime and 17 days (range, 8-28 days) for ceftriaxone (P < .01). All follow-up cultures were negative. NAAT positivity was higher for cefixime (45.0%) compared to ceftriaxone (17.7%) (P = .014); all were positive at the pharynx, and 1 was also positive rectally. In multivariate analysis, higher initial NAAT cycle threshold values (adjusted odds ratio [aOR], 0.81 [95% confidence interval {CI}, .70-.92]) and ceftriaxone treatment (aOR, 0.11 [95% CI, .02-.61]) were associated with lower odds of positivity at TOC.

CONCLUSIONS

Among N. gonorrhoeae infections treated with oral cefixime, we found no positive cultures at follow-up. Higher NAAT positivity among those treated with cefixime could reflect slower clearance at pharyngeal sites. However, persistent detection by NAATs at pharyngeal sites suggests the presence of nonviable bacteria, a limitation of the tests.