Identification of demographic and behavioral risk factors for antibiotic resistant gonorrhea infections to combat the emergence of potentially untreatable infections.

Copyright © 20 Identification of Demographic and Behavioral Risk Factors for Antibiotic Resistant Gonorrhea Infections to Combat the Emergence of Potentially Untreatable Infections Molly A. Trecker, MPH*† and Jo-Anne R. Dillon, PhD†‡ The research by Cole et al. in this issue of Sexually Transmitted Diseases highlights a number of important findings related to behavioral and demographic risk factors for antimicrobial resistance (AMR—i.e., resistance to ceftriaxone, cefixime, azithromycin, and ciprofloxacin) in people infected with Neisseria gonorrhoeae. They found that heterosexuals, people older than 25 years, and persons not concurrently infected with chlamydia were more likely to carry infections resistant to cefixime and/or ciprofloxacin. More surprisingly, Cole et al. report a significant decrease in the geometric mean of European gonococcal cefixime and ceftriaxone minimum inhibitory concentrations (MICs) between 2009 and 2011, especially among men who have sex with men (MSM). In 2011, heterosexual men exhibited the highest MICs to both these antibiotics as compared with MSM and women. Univariate and multivariate analyses of the risk factors associated with gonococcal resistance to ciprofloxacin, cefixime, and azithromycin indicated that slightly different risk factors were associated with resistance to the different antibiotics. For example, azithromycin resistance (univariate analysis) was associated with male heterosexuals, no concurrent chlamydial infections, or previous gonorrhea, and year of isolation was negatively associated with this resistance. In the multivariate analysis of gonococcal azithromycin resistance, only no concurrent chlamydial infection and year of isolation were significant. Interestingly, isolates from the pharynx were not more likely to be associated with resistance to azithromycin, ciprofloxacin, or cefixime. This finding contrasts with research indicating that resistance to third-generation cephalosporins is associated with horizontal gene transfer from commensalNeisseria species carried in the pharynx to N. gonorrhoeae isolates. The findings by Cole et al. are important because they provide evidence useful for identifying individuals potentially at higher risk for acquiring AMR gonorrhea infections. This study also adds to the very small number of published studies that link comprehensive epidemiological data with antimicrobial susceptibility data to identify potential behavioral and demographic risk factors for AMR gonorrhea infections. In this era of rising gonococcal resistance to the last class of antibiotic used in monotherapy, the third-generation cephalosporins, and facing the threat of potentially untreatable infections, the application of behavioral and demographic factors, which can be elicited in a clinical visit, to identify those at higher risk for AMR infection could play a central role in tailoring effective policies to combat resistant infections. The current literature regarding behavioral and demographic risk factors associated with gonococcal AMR identifies a number of factors associated with increased MICs to various antibiotics. Being in an older age group, for example, has been found in previous studies to be associated with probable resistance or resistance to ceftriaxone, quinolones, and azithromycin. In addition, association of male (heterosexual) sex and increased MICs to tetracycline and ceftriaxone and to quinolones has been previously reported. A 2014 study found an association between alcohol use and tetracycline resistance, which was interpreted as a potential marker for other, more proximate risk behaviors, such as having multiple sex partners, which might be more plausibly associated with resistant infection. Several studies from the previous decade have identified an association of resistance tovarious antibioticswithMSM. Other factors found to be associated with gonorrhea infections resistant to quinolones include recent antibiotic use and race/ethnicity, and, among sex workers, self-prescribed antibiotic use. Lastly, one study found sex with a female sex worker to be associated with resistance to azithromycin. The type of information produced by Cole et al. in analyzing the association of demographic and behavioral risk factors and gonococcal AMR is extraordinarily difficult to obtain, and the authors point out