JAC Advance Access originally published online on June 27, 2006
Journal of Antimicrobial Chemotherapy 2006 58(3):580-586; doi:10.1093/jac/dkl264
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Comparability of laboratory diagnosis and antimicrobial susceptibility testing of Neisseria gonorrhoeae from reference laboratories in Western Europe
1 Sexually Transmitted Bacteria Reference Laboratory, Health Protection Agency Centre for Infections 61 Colindale Avenue, London NW9 5HT, UK 2 Department of HIV and Sexually Transmitted Infections, Health Protection Agency Centre for Infections 61 Colindale Avenue, London NW9 5HT, UK
Received 27 March 2006; returned 19 April 2006; revised 31 May 2006; accepted 1 June 2006
*Corresponding author. Tel: +44-208-327-6462; Fax: +44-208-327-6081; E-mail: catherine.ison{at}hpa.org.uk
Objectives: The aim of this study was to obtain information on the comparability of methods for the laboratory diagnosis of bacterial sexually transmitted infections (STIs) that contribute to the surveillance data in the European Union (EU) and Norway. Surveillance of bacterial STIs is important across Europe because of the movement of individuals between countries at a time when STI incidence appears to be increasing in many countries.
Methods: Cross-sectional survey using a questionnaire, to provide information on laboratory methods for the diagnosis of gonorrhoea, and a panel of strains of Neisseria gonorrhoeae, to compare susceptibility testing, was circulated to laboratories in the EU and Norway.
Results: The questionnaire revealed marked diversity in the methodologies used for the laboratory diagnosis of gonorrhoea across Europe. Fourteen laboratories participated in an exchange of gonococcal strains to assess the methodology in current use for susceptibility testing. The methods included disc diffusion and determination of the minimum inhibitory concentration (MIC) using agar dilution and/or Etest. There was no common method used, each centre varied from another by at least one procedure. Overall agreement using all methods was >70%, being highest for ceftriaxone and lowest for tetracycline. Disc diffusion gave the lowest agreement with the consensus compared with determination of MIC by either agar dilution or Etest.
Conclusions: A variety of methods were used across the EU and Norway for the laboratory diagnosis and susceptibility testing and resulted in poor concordance between laboratories on the definition of resistant N. gonorrhoeae. This suggests that there is a need for greater standardization of methodology that provides surveillance data in the EU and Norway.
Keywords: gonorrhoea , surveillance , quality assurance