Preparing for an era of untreatable gonorrhea

Abstract

Purpose of review: The proportion of Neisseria gonorrhoeae isolates with reduced susceptibility to extended-spectrum cephalosporins (ESCs) has increased rapidly since 2006. Clinicians, researchers, and public health officials need to be prepared for the possibility of an era of untreatable gonorrhea. This review focuses on the evidence for current gonorrhea treatment recommendations, potential future treatment options, and other methods to control gonorrhea.

Recent findings: In addition to an increase in isolates with decreased susceptibility to ESCs, there have been reported treatment failures to both cefixime and ceftriaxone. In response, some countries have increased the recommended cephalosporin dose, and most now recommend dual therapy with an ESC and azithromycin. The pharynx has been implicated as a site for acquiring resistance through transformation with commensal Neisseria species or induced resistance through subtherapeutic antimicrobial levels. Thus, appropriate screening of the pharynx and treatment with a regimen that eradicates gonorrhea from the pharynx is necessary. At present, several studies are evaluating various novel treatment regimens in preparation for an era of untreatable gonorrhea.

Summary: Screening for asymptomatic infections, maintaining culture capacity to monitor antimicrobial resistance, treating with ceftriaxone and azithromycin, and ensuring that all sexual partners are treated are among the best strategies to control gonorrhea in the current clime.

Figure 1

Proportion of Gonococcal Isolates tested by Gonococcal Isolate Surveillance Program (GISP) with CDC 'alert value' MIC§ to Cefixime*, Ceftriaxone, Azithromycin; 2007 – 2012 ^§CDC defines alert value MIC to cefixime as ≥0.25 µg/mL, ceftriaxone ≥0.125 µg/mL, and Azithromycin ≥2.0 µg/mL. *Cefixime MIC were not tested in 2007 and 2008. Data compiled from CDC STD Surveillance Reports 2007 – 2012.