Introduction Euro-GASP antimicrobial resistance (AMR) data informs gonorrhoea (GC) treatment guidelines, therefore the data needs to be robust and reliable. We assessed whether Euro-GASP appropriately reflects the AMR situation across Europe.

Methods We compared data from Euro-GASP and national systems from 12 countries for azithromycin (AZ), cefixime (CEF) and ciprofloxacin (CIP) from 2009–2013 and performed Poisson regression to identify differences (p<0.05) between the proportions of resistant isolates in Euro-GASP and national data sets. The 2014 Euro-GASP AMR data for each country (n=19) were weighted to account for differences according to patient characteristics (age group, sexual orientation and gender) between the Euro-GASP patient data and the European STI surveillance data. Data were compared to determine whether resistance levels shifted above or below the 5% threshold used to assess the clinical utility of GC treatments.

Results Euro-GASP isolates were more likely to be resistant for AZ (incidence-rate ratio (IRR) 1.3, 1.1–1.5 95% confidence interval (CI), p=0.003) and less likely to be resistant for CEF (IRR 0.8, 0.7–0.9 95% CI, p=0.007) compared to the national data. There was no significant difference for CIP.

Weighting slightly altered the estimates of overall AMR (−4.7%–4.7% difference). More apparent differences for AZ and CIP (9.5%–17.9%) were observed for countries with low isolate numbers and low completeness of reporting (n=3). Weighting caused AMR levels to cross the 5% threshold in one country (CEF 5% to 3.4%).

Conclusion The comparability of resistance proportions was satisfactory for CIP; MICs for CIP-resistant gonococci were mostly well above the resistance breakpoint, so testing and interpretation remained reliable. The differences for CEF and AZ resistance proportions were likely due to variability induced by strains with MICs close to the resistance breakpoints. Weighting of the Euro-GASP 2014 data provided similar estimates of AMR, demonstrating that Euro-GASP laboratories submit representative isolates in respect to patient characteristics.