title: Drifting towards ceftriaxone treatment failure in gonorrhoea: risk factor analysis of data from the Gonococcal Resistance to Antimicrobials Surveillance Programme in England and Wales.
abstract: OBJECTIVE
  Treatment of Neisseria gonorrhoeae is threatened by the emergence of antimicrobial resistance. We analysed data from the Gonococcal Resistance to Antimicrobials Surveillance Programme (GRASP) in England and Wales to identify groups most at risk of reduced susceptibility to the currently recommended first-line therapy, ceftriaxone.
  
  
  METHODS
  Data from GRASP between 2007 and 2013 on ceftriaxone susceptibility and strain types were analysed. Risk factors associated with isolates exhibiting a ceftriaxone minimum inhibitory concentration (MIC) of ≥0.015 mg/L (CTR ≥0.015 mg/L) were identified using logistic regression.
  
  
  RESULTS
  One third of isolates from men who have sex with men (MSM) (1279/4203) and 9.9% from heterosexuals (458/4626) exhibited CTR ≥0.015 mg/L. Between 2007 and 2013, the modal MIC for isolates remained at 0.004 mg/L for MSM but increased from 0.002 to 0.004 mg/L for heterosexuals. Among MSM, CTR ≥0.015 mg/L was associated with Asian ethnicity (crude OR: 1.42; 95% CI 1.07 to 1.88) and previous gonorrhoea (1.34; 1.16 to 1.54). Among heterosexuals, CTR ≥0.015 mg/L was associated with older age (35+ years: 4.31; 3.34 to 5.55), ≥6 sexual partners (1.58; 1.01 to 2.44) and sex abroad (2.23; 1.71 to 2.91). CTR ≥0.015 mg/L was less likely in isolates from heterosexuals of black Caribbean or African ethnicity (0.29; 0.20 to 0.41, 0.66; 0.43 to 0.99), with a concurrent chlamydial infection (0.25; 0.19 to 0.34) or women (0.57; 0.46 to 0.71). Over 600 isolates (CTR ≥0.015 mg/L) were typed; the majority were in Genogroup 1407, containing sequence type 1407.
  
  
  CONCLUSIONS
  The emergence and spread of gonorrhoea with reduced susceptibility to ceftriaxone seems a realistic prospect, most likely in those involved in 'rapid-transmission' or bridging sexual networks.
authors.affiliation: HIV/STI Department, National Infection Service, Public Health England, London, UK.
authors.forename: K
authors.initials: K
authors.lastname: Town
authors.affiliation: HIV/STI Department, National Infection Service, Public Health England, London, UK.
authors.forename: C
authors.initials: C
authors.lastname: Obi
authors.affiliation: Sexually Transmitted Bacteria Reference Unit, National Infection Service, Public Health England, London, UK.
authors.forename: N
authors.initials: N
authors.lastname: Quaye
authors.affiliation: Sexually Transmitted Bacteria Reference Unit, National Infection Service, Public Health England, London, UK.
authors.forename: S
authors.initials: S
authors.lastname: Chisholm
authors.affiliation: HIV/STI Department, National Infection Service, Public Health England, London, UK.
authors.forename: G
authors.initials: G
authors.lastname: Hughes
mesh_terms: D000900:Anti-Bacterial Agents / Q000627:therapeutic use*; D002443:Ceftriaxone / Q000627:therapeutic use*; D024901:Drug Resistance, Multiple, Bacterial / Q000187:drug effects* / Q000235:genetics; D004739:England / Q000453:epidemiology; D005163:Factor Analysis, Statistical; D006069:Gonorrhea / Q000188:drug therapy / Q000453:epidemiology*; D006801:Humans; D008826:Microbial Sensitivity Tests; D009344:Neisseria gonorrhoeae / Q000187:drug effects* / Q000302:isolation & purification; D015995:Prevalence; D012307:Risk Factors; D018571:Sentinel Surveillance; D012725:Sexual Behavior / Q000706:statistics & numerical data*; D012747:Sexual Partners; D017211:Treatment Failure; D014852:Wales / Q000453:epidemiology
chemical_list: D000900:Anti-Bacterial Agents; D002443:Ceftriaxone
keywords: ANTIBIOTIC RESISTANCE; EPIDEMIOLOGY (GENERAL); GENITOURINARY MEDICINE; NEISSERIA GONORRHOEA; PUBLIC HEALTH