title: Prevalence and characteristics of gastrointestinal infections in men who have sex with men diagnosed with rectal chlamydia infection in the UK: an 'unlinked anonymous' cross-sectional study.
abstract: Gastrointestinal infections (GII) can cause serious ill health and morbidity. Although primarily transmitted through faecal contamination of food or water, transmission through sexual activity is well described, especially among men who have sex with men (MSM).
  
  
  
  We investigated the prevalence of GIIs among a convenience sample of MSM who were consecutively diagnosed with rectalChlamydia trachomatis(CT) at 12 UK genitourinary medicine clinics during 10 weeks in 2012. Residual rectal swabs were coded, anonymised and tested forShigella,Campylobacter,Salmonella, shiga toxin-producingEscherichia coliand enteroaggregativeE. coli(EAEC) using a real-time PCR. Results were linked to respective coded and anonymised clinical and demographic data. Associations were investigated using Fisher's exact tests.
  
  
  
  Of 444 specimens tested, overall GII prevalence was 8.6% (95% CI 6.3% to 11.6%): 1.8% (0.9% to 3.6%) tested positive forShigella, 1.8% (0.9% to 3.6%) forCampylobacterand 5.2% (3.5% to 7.7%) for EAEC. No specimens tested positive forSalmonellaor other diarrhoeagenicE. colipathotypes. Among those with any GII, 14/30 were asymptomatic (2/7 withShigella, 3/6 withCampylobacterand 9/17 with EAEC).Shigellaprevalence was higher in MSM who were HIV-positive (4.7% (2.1% to 10.2%) vs 0.5%(0.1% to 3.2%) in HIV-negative MSM; p=0.01).
  
  
  
  In this small feasibility study, MSM with rectal CT appeared to be at appreciable risk of GII. Asymptomatic carriage may play a role in sexual transmission of GII.
authors.affiliation: Department of HIV and STI, National Infection Service, Public Health England, London, UK.
authors.forename: Gwenda
authors.identifier: 0000-0003-2090-7702
authors.initials: G
authors.lastname: Hughes
authors.affiliation: Gastrointestinal Infection Reference Service, Microbiology Services Centre, National Infection Service, Public Health England, London, UK.
authors.forename: Panida
authors.initials: P
authors.lastname: Silalang
authors.affiliation: Department of HIV and STI, National Infection Service, Public Health England, London, UK.
authors.forename: John
authors.initials: J
authors.lastname: Were
authors.affiliation: Sexually Transmitted Infection Reference Service, Microbiology Services Centre, National Infection Service, Public Health England, London, UK.
authors.forename: Hemanti
authors.initials: H
authors.lastname: Patel
authors.affiliation: Gastrointestinal Infection Reference Service, Microbiology Services Centre, National Infection Service, Public Health England, London, UK.
authors.forename: Tristan
authors.initials: T
authors.lastname: Childs
authors.affiliation: Sexually Transmitted Infection Reference Service, Microbiology Services Centre, National Infection Service, Public Health England, London, UK.
authors.forename: Sarah
authors.initials: S
authors.lastname: Alexander
authors.affiliation: Department of HIV and STI, National Infection Service, Public Health England, London, UK.
authors.forename: Stephen
authors.initials: S
authors.lastname: Duffell
authors.affiliation: Department of Sexual Medicine and HIV, University Hospitals of South Manchester NHS Foundation Trust, Manchester, UK.
authors.forename: Cara
authors.initials: C
authors.lastname: Saxon
authors.affiliation: Sexually Transmitted Infection Reference Service, Microbiology Services Centre, National Infection Service, Public Health England, London, UK.
authors.forename: Cathy
authors.initials: C
authors.lastname: Ison
authors.affiliation: Department of HIV and STI, National Infection Service, Public Health England, London, UK.|Research Department of Infection and Population Health, University College London, London, UK.
authors.forename: Holly
authors.initials: H
authors.lastname: Mitchell
authors.affiliation: Department of HIV and STI, National Infection Service, Public Health England, London, UK.|Research Department of Infection and Population Health, University College London, London, UK.
authors.forename: Nigel
authors.initials: N
authors.lastname: Field
authors.affiliation: Gastrointestinal Infection Reference Service, Microbiology Services Centre, National Infection Service, Public Health England, London, UK.
authors.forename: Claire
authors.initials: C
authors.lastname: Jenkins
mesh_terms: D000328:Adult; D058345:Asymptomatic Infections / Q000453:epidemiology; D002690:Chlamydia Infections / Q000175:diagnosis / Q000453:epidemiology* / Q000382:microbiology / Q000635:transmission; D002692:Chlamydia trachomatis / Q000235:genetics / Q000302:isolation & purification; D003430:Cross-Sectional Studies; D004926:Escherichia coli / Q000235:genetics / Q000302:isolation & purification; D004927:Escherichia coli Infections / Q000453:epidemiology; D005240:Feasibility Studies; D005767:Gastrointestinal Diseases / Q000453:epidemiology* / Q000209:etiology / Q000382:microbiology; D006069:Gonorrhea / Q000453:epidemiology; D018451:Homosexuality, Male; D006801:Humans; D008297:Male; D008403:Mass Screening; D009344:Neisseria gonorrhoeae / Q000235:genetics / Q000302:isolation & purification; D016133:Polymerase Chain Reaction; D015995:Prevalence; D012002:Rectal Diseases / Q000175:diagnosis / Q000453:epidemiology* / Q000382:microbiology; D012007:Rectum / Q000382:microbiology*; D012307:Risk Factors; D012725:Sexual Behavior; D015231:Sexually Transmitted Diseases, Bacterial / Q000150:complications / Q000453:epidemiology / Q000382:microbiology; D006113:United Kingdom / Q000453:epidemiology
keywords: EPIDEMIOLOGY (GENERAL); GASTROINTESTINAL; GAY MEN; INFECTION