Article Text

Download PDFPDF
Evaluation of ligase chain reaction for the non-cultural detection of rectal and pharyngeal gonorrhoea in men who have sex with men
  1. H Young1,
  2. K Manavi2,
  3. A McMillan2
  1. 1Scottish Neisseria gonorrhoeae Reference Laboratory, Lothian University Hospitals NHS Trust, The Royal Infirmary of Edinburgh, 51 Little France Crescent, Edinburgh EH16 4SA, UK
  2. 2Department of Genitourinary Medicine, Lothian University Hospitals NHS Trust, Lauriston Building, Lauriston Place, Edinburgh, UK
  1. Correspondence to:
 Dr Hugh Young
 Scottish Neisseria gonorrhoeae Reference Laboratory, Directorate of Medical Microbiology, The Royal Infirmary of Edinburgh, 51 Little France Crescent, Edinburgh EH16 4SA, UK; Hugh.Youngluht.scot.nhs.uk

Abstract

Objectives: To compare a nucleic acid amplification test (ligase chain reaction) with culture for detecting rectal and pharyngeal gonorrhoea in men who have sex with men (MSM).

Methods: Duplicate rectal and throat swabs from MSM attending a genitourinary medicine clinic were collected for culture on modified New York City medium and detection of gonococcal nucleic acid by the Abbott ligase chain reaction (LCR) utilising probes based on opa 1 gene sequences. LCR positive culture negative specimens were tested by a second LCR utilising probes based on pilin gene sequences. Patients with rectal and/or pharyngeal cultures yielding Gram negative diplococci confirmed as Neisseria gonorrhoeae by biochemical and immunological methods were diagnosed with rectal and/or pharyngeal gonorrhoea. The criteria for diagnosing rectal and pharyngeal infection by LCR included a positive opa LCR with a positive culture from the same site or, in the case of a negative culture, a positive opa LCR and a positive pilin LCR.

Results: Duplicate rectal samples were obtained from 227 MSM. The results of LCR and culture were concordant in 219 samples (96.5%). The prevalence of rectal gonorrhoea by LCR and culture was 7.0% (16/227) and 4.0% (9/227), respectively. Duplicate throat samples were obtained from 251 MSM. The results of LCR and culture were concordant in 230 (91.6%) cases. The prevalence of pharyngeal gonorrhoea by LCR and culture was 12.7% (32/251) and 6.0% (15/251), respectively. The specificity of LCR was 99.5% (210/211) for rectal and 98.2% (215/219) for pharyngeal specimens.

Conclusions: The high prevalence and asymptomatic nature of pharyngeal and rectal gonococcal infection suggests that routine screening for infection at these sites by a nucleic acid amplification test method such as LCR should be considered as part of the overall strategy to control gonorrhoea in MSM.

  • gonorrhoea
  • MSM
  • ligase chain reaction

Statistics from Altmetric.com

Request Permissions

If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.

Footnotes

Linked Articles

  • Brief Encounters
    Helen Ward