Objectives: To describe trends in prevalence, susceptibility profile and risk factors for MDR Neisseria gonorrhoeae (MDR-NG) in England and Wales.
Methods: Isolates from 16 242 gonorrhoea episodes at sexual health clinics within the Gonococcal Resistance to Antimicrobials Surveillance Programme (GRASP) underwent antimicrobial susceptibility testing. MDR-NG was defined as resistance to ceftriaxone, cefixime or azithromycin, plus at least two of penicillin, ciprofloxacin and spectinomycin. Trends in resistance are presented for 2004-15; prevalence and logistic regression analyses for MDR-NG cover the period of the most recent treatment guideline (ceftriaxone plus azithromycin), 2011-15.
Results: Between 2004 and 2015, the proportion of N. gonorrhoeae isolates fully susceptible to all antimicrobial classes fell from 80% to 46%, with the proportion resistant to multiple (two or more) classes increasing from 7.3% to 17.5%. In 2011-15, 3.5% of isolates were MDR-NG, most of which were resistant to cefixime (100% in 2011, decreasing to 36.9% in 2015) and/or azithromycin (4.2% in 2011, increasing to 84.3% in 2015). After excluding azithromycin-resistant isolates, modal azithromycin MICs were higher in MDR versus non-MDR isolates (0.5 versus 0.125 mg/L), with similar results for ceftriaxone (modal MICs 0.03 versus ≤0.002 mg/L). After adjustment for confounders, MDR-NG was more common among isolates from heterosexual men, although absolute differences in prevalence were small [4.6% versus 3.3% (MSM) and 2.5% (women)].
Conclusions: N. gonorrhoeae is becoming less susceptible to available antimicrobials. Since 2011, a minority of isolates were MDR-NG; however, MICs of azithromycin or ceftriaxone (first-line therapies) for many of these were elevated. These findings highlight the importance of continued antimicrobial stewardship for gonorrhoea.