P632 Regional differences in gonorrhoea antimicrobial resistance patterns in the netherlands

Background The Gonococcal Resistance to Antibiotics Surveillance (GRAS) programme was established in the Netherlands to monitor gonorrhoea resistance patterns. Until now, GRAS data were only analysed and presented on a national level. This study aims to gain insight into regional differences and the representativeness of GRAS. Methods 18 STI clinics participate in GRAS and monitor resistance to azithromycin, ciprofloxacin, cefotaxime and ceftriaxone by performing culture and susceptibility testing with Etest for gonorrhoea patients. To describe differences in antimicrobial resistance levels between STI clinic regions, data from 2013–2017 was used. Antimicrobial resistance was defined based on EUCAST breakpoints. For azithromycin and ciprofloxacin, variables associated with resistance in univariate analyses were added to a multilevel logistic regression model containing a random intercept for region. We calculated the proportional change in variance (PCV) to assess to what extend regional variance in antibiotic resistance was explained by these variables. We included patient characteristics (e.g. sex, age, ethnicity, anatomical location of infection) and laboratory characteristics (sample method and selective culture medium). Results In 2013–2017, almost 9,000 susceptibility tests were performed. Resistance to azithromycin was 11.6% (varying between regions from 2.0%–41.5%), ciprofloxacin 29.4% (12.8%–61.1%), cefotaxime 2.0% (0.0%–4.2%) and ceftriaxone 0.0%. The PCV after adding patient characteristics to the model was 73.8% for ciprofloxacin, but for azithromycin −17.8%. For laboratory characteristics, these were 32.8% and 36.6%. Adding both patient and laboratory characteristics explained 78.6% of regional variance for ciprofloxacin, and 15.5% for azithromycin. Conclusion Regional variations in antimicrobial resistance are reported, and need to be taken into account when interpreting national surveillance data. Further research is needed to determine the cause of these regional differences, including an evaluation of regional laboratory practices. Especially for azithromycin, as regional variance could not be explained by population characteristics. Disclosure No significant relationships.