The epidemiology of ciprofloxacin resistant isolates of Neisseria gonorrhoeae in Scotland 2002:: a comparison of phenotypic and genotypic analysis

Objectives: To characterise all isolates with reduced susceptibility or resistance to ciprofloxacin received by the Scottish Neisseria gonorrhoeae Reference Laboratory (SNGRL) in 2002 using N gonorrhoeae multiantigen sequence typing (NG-MAST); to compare NG-MAST with conventional typing and to describe the epidemiology of ciprofloxacin resistant gonorrhoea in Scotland in 2002. Methods: Isolates were characterised on receipt by auxotyping and serotyping (A/S typing), and antibiotic susceptibility testing, and retrospectively by NG-MAST. Epidemiological data were requested for all isolates in the study. Results: The 106 isolates were separated into more sequence types (ST) than A/S classes ( 44 versus 17). All isolates within a sequence type had the same serotype, were homogeneous with respect to ciprofloxacin resistance category, but were sometimes heterogeneous with respect to auxotype or plasmid borne resistance to penicillin. Combined NG-MAST and epidemiological data revealed sustained transmission of several gonococcal strains predominantly within Greater Glasgow and Lothian. Clusters of isolates were associated with transmission within the United Kingdom, whereas isolates with unique STs were associated with foreign travel ( p< 0.0001). Conclusions: NG-MAST is more discriminatory than A/S typing. Ciprofloxacin resistant gonococcal isolates in Scotland are heterogeneous, with endemic spread of some strains occurring predominantly in Greater Glasgow and Lothian.