Chlamydia trachomatis and Neisseria gonorrhoeae infection and the sexual behaviour of men who have sex with men
- 1Department of Genitourinary Medicine, Mortimer Market Centre, Camden Primary Care Trust, London, UK
- 2Sexual Health Department, Swindon and Marlborough NHS Trust, Swindon, UK
- 3Department of Clinical Microbiology, University College Hospital NHS Foundation Trust, London, UK
- 4Department of Sexually Transmitted Diseases, Mortimer Market Centre, Royal Free and University College London Medical Schools, London, UK
- Correspondence to: Dr P Benn Department of Genitourinary Medicine, Mortimer Market Centre, Off Capper Street, London WC1B 6AU, UK;
- Accepted 4 September 2006
- Published Online First 4 October 2006
Background: : Rates of bacterial sexually transmitted infections (STIs) continue to rise among men who have sex with men (MSM) in the UK.
Objective: To evaluate factors associated with Chlamydia trachomatis and Neisseria gonorrhoeae among MSM attending a genitourinary medicine clinic in inner London.
Study design: : 599 MSM undergoing testing for STIs were recruited. Specimens for ligase chain reaction (LCR), strand displacement amplification (SDA) assay and culture were collected from the pharynx, urethra and rectum for the detection of C trachomatis and N gonorrhoeae. Details regarding demographics, symptoms, signs and sexual behaviour were recorded. Associations of these factors with each infection were tested, adjusting for other risk factors.
Results: The prevalence of C trachomatis and N gonorrhoeae was 11.0% and 16.0%, respectively. LCR and SDA performed well for the detection of C trachomatis and N gonorrhoeae from urethra and rectum. Using either method, compared with our current testing policy, over 18% of those with C trachomatis and N gonorrhoeae would not have had their infection diagnosed or treated. Age, sexual behaviour, urethral and rectal symptoms and signs were strongly associated with both infections. A total of 33.7% of men reported at least one episode of unprotected anal intercourse in the previous month. Men reporting multiple episodes were markedly more likely to be HIV positive.
Conclusion: The prevalence of infection, rates of partner acquisition and unprotected anal intercourse reported among these MSM are alarming. Improved detection of C trachomatis and N gonorrhoeae using nucleic acid amplification tests has major public health implications for STI and possibly HIV transmission in this population.
- LCR, ligase chain reaction
- MSM, men who have sex with men
- NAAT, nucleic acid amplification test
- SDA, strand displacement amplification
- STI, sexually transmitted infection
Published Online First 4 October 2006
Competing interests: None declared.
Ethical approval: This study was reviewed and given approval by the Camden & Islington Community Health Services Trust Ethics Committee.
Recommendations: Routine NAAT testing for Chlamydia trachomatis and Neisseria gonorrhoeae from the rectum, in addition to the urethra, among MSM and associated cost implications must be considered. Further work is required before NAAT testing from the pharynx can be recommended.
Contributors: PDB coordinated the study, tested the samples and wrote the manuscript; GR devised the study and contributed to the manuscript; CC tested the samples and contributed to the manuscript; MB recruited patients; SRS tested the samples; AC undertook statistical analysis and contributed to the manuscript; AJR supervised the study and contributed to the manuscript; and GLR supervised the study and contributed to the manuscript.