title: High co-occurrence of anorectal chlamydia with urogenital chlamydia in women visiting an STI clinic revealed by routine universal testing in an observational study; a recommendation towards a better anorectal chlamydia control in women.
abstract: BACKGROUND
  Symptom- and sexual history-based testing i.e., testing on indication, for anorectal sexually transmitted infections (STIs) in women is common. Yet, it is unknown whether this strategy is effective. Moreover, little is known about alternative transmission routes i.e. by fingers/toys. This study assesses anorectal STI prevalence and infections missed by current testing practice, thereby informing the optimal control strategy for anorectal STIs in women.
  
  
  METHODS
  Women (n = 663) attending our STI-clinic between May 2012-July 2013 were offered routine testing for anorectal and urogenital Chlamydia trachomatis and Neisseria gonorrhoeae. Data were collected on demographics, sexual behaviour and symptoms. Women were assigned to one of the categories: indication (reported anal sex/symptoms), fingers/toys (only reported use of fingers/toys), or without indication.
  
  
  RESULTS
  Of women, 92% (n = 654) participated. There were 203 reports (31.0%) of anal sex and/or symptoms (indication), 48 reports (7.3%) of only using fingers/toys (fingers/toys), and 403 reports (61.6%) of no anal symptoms, no anal sex and no anal use of fingers/toys (without indication). The overall prevalence was 11.2% (73/654) for urogenital chlamydia and 8.4% (55/654) for anorectal chlamydia. Gonorrhoea infections were not observed. Prevalence of anorectal chlamydia was 7.9% (16/203) for women with indication and 8.6% (39/451) for all other women (P = 0.74). Two-thirds (39/55) of anorectal infections were diagnosed in women without indication. Isolated anorectal chlamydia was rare (n = 3): of all women with an anorectal infection, 94.5% (52/55) also had co-occurrence of urogenital chlamydia. Of all women with urogenital chlamydia, 71.2% (52/73) also had anorectal chlamydia.
  
  
  CONCLUSIONS
  Current selective testing on indication of symptoms and sexual history is not an appropriate control strategy for anorectal chlamydia in women visiting an STI clinic. Routine universal anorectal testing is feasible and may be a possible control strategy in women. Yet costs may be a problem. When more restricted control measures are preferred, possible alternatives include (1) anorectal testing only in women with urogenital chlamydia (problem: treatment delay or loss to follow up), and (2) direct treatment for urogenital chlamydia that is effective for anorectal chlamydia as well.
authors.affiliation: Department of Sexual Health, Infectious Diseases and Environmental Health, South Limburg Public Health Service, 6160, HA Geleen, Netherlands. genevieve.vanliere@ggdzl.nl.
authors.forename: Geneviève A F S
authors.initials: GA
authors.lastname: van Liere
authors.forename: Christian J P A
authors.initials: CJ
authors.lastname: Hoebe
authors.forename: Petra F G
authors.initials: PF
authors.lastname: Wolffs
authors.forename: Nicole H T M
authors.initials: NH
authors.lastname: Dukers-Muijrers
mesh_terms: D000328:Adult; D000554:Ambulatory Care Facilities; D001003:Anal Canal / Q000382:microbiology; D001004:Anus Diseases / Q000453:epidemiology* / Q000382:microbiology; D002690:Chlamydia Infections / Q000453:epidemiology*; D002692:Chlamydia trachomatis / Q000302:isolation & purification*; D005260:Female; D006069:Gonorrhea / Q000453:epidemiology*; D006801:Humans; D009344:Neisseria gonorrhoeae / Q000302:isolation & purification*; D009426:Netherlands / Q000453:epidemiology; D015995:Prevalence; D012725:Sexual Behavior; D012749:Sexually Transmitted Diseases / Q000453:epidemiology; D014566:Urogenital System / Q000382:microbiology; D055815:Young Adult