title: What would be missed if we didn't screen men who have sex with men for oral chlamydia trachomatis? A cross-sectional study.
abstract: Background This study aimed to describe oropharyngeal chlamydia (OCT) in gay and bisexually active men (GBM) attending a large urban sexual health clinic in Sydney and determine what proportion of cases would be missed if screening was not routine.
  
  
  METHODS
  Retrospective data were extracted for all GBM with a positive OCT result between 1 October 2012 and 31 April 2014. The control group consisted of patients who had a negative OCT result on their first visit during the study period, and each patient was only counted once.
  
  
  RESULTS
  A total of 74 of 2920 GBM (0.03, 95% CI: 0.02-0.03) were diagnosed with OCT. The 2920 GBM had a total of 11226 OCT tests performed, demonstrating OCT test positivity of 0.006 (95% CI: 0.005-0.008). A total of 62 sexually transmissible infections (STIs) were diagnosed at other sites: 34 rectal chlamydia (CT), 12 throat gonorrohea (GC), 7 urine CT, 7 rectal GC, 1 infectious syphilis and 1 non-gonoccal urethritis (NGU) case. Of the 74 OCT cases, 56 (0.76, 95% CI: 0.64-0.85) were treated with Azithromycin; 51 (69%) as part of standard treatment for their STI co-infection (34 rectal CT, 12 throat GC, 7 urine CT, 7 rectal GC, 1 NGU case) and a further five (7%) were treated as contacts. The remaining 18 people (0.24, 95% CI: 0.15-0.36) would not have been treated unless they were tested specifically for OCT.
  
  
  CONCLUSIONS
  Overall, two-thirds of the OCT cases received appropriate treatment and only a small number of cases would have been missed had routine screening not been performed. With an extremely low overall test positivity of 0.6%, screening for OCT at our service adds little to population level health control.
authors.affiliation: Sydney Sexual Health Centre, South East Sydney Local Health District, Sydney, NSW 2000, Australia.
authors.forename: Priya
authors.initials: P
authors.lastname: Loomba
authors.affiliation: Sydney Sexual Health Centre, South East Sydney Local Health District, Sydney, NSW 2000, Australia.
authors.forename: Vickie
authors.initials: V
authors.lastname: Knight
authors.affiliation: Sydney Sexual Health Centre, South East Sydney Local Health District, Sydney, NSW 2000, Australia.
authors.forename: Anna
authors.initials: A
authors.lastname: McNulty
mesh_terms: D000328:Adult; D002690:Chlamydia Infections / Q000175:diagnosis*; D002692:Chlamydia trachomatis / Q000302:isolation & purification*; D003430:Cross-Sectional Studies; D006069:Gonorrhea; D018451:Homosexuality, Male; D006801:Humans; D008297:Male; D008403:Mass Screening; D009059:Mouth Diseases / Q000175:diagnosis*; D015995:Prevalence; D012189:Retrospective Studies; D000072339:Sexual and Gender Minorities