title: The "3 in 1" Study: Pooling Self-Taken Pharyngeal, Urethral, and Rectal Samples into a Single Sample for Analysis for Detection of Neisseria gonorrhoeae and Chlamydia trachomatis in Men Who Have Sex with Men.
abstract: Triple-site testing (using pharyngeal, rectal, and urethral/first-void urine samples) for Neisseria gonorrhoeae and Chlamydia trachomatis using nucleic acid amplification tests detects greater numbers of infections among men who have sex with men (MSM). However, triple-site testing represents a cost pressure for services. MSM over 18 years of age were eligible if they requested testing for sexually transmitted infections (STIs), reported recent sexual contact with either C. trachomatis or N. gonorrhoeae, or had symptoms of an STI. Each patient underwent standard-of-care (SOC) triple-site testing, and swabs were taken to form a pooled sample (PS) (pharyngeal, rectal, and urine specimens). The PS was created using two methods during different periods at one clinic, but we analyzed the data in combination because the sensitivity of the two methods did not differ significantly for C. trachomatis (P = 0.774) or N. gonorrhoeae (P = 0.163). The sensitivity of PS testing (92%) was slightly lower than that of SOC testing (96%) for detecting C. trachomatis (P = 0.167). For N. gonorrhoeae, the sensitivity of PS testing (90%) was significantly lower than that of SOC testing (99%) (P < 0.001). When pharynx-only infections were excluded, the sensitivity of PS testing to detect N. gonorrhoeae infections increased to 94%. Our findings show that pooling of self-taken samples could be an effective and cost-saving method, with high negative predictive values. (Interim results of this study were presented at the BASHH 2013 summer meeting.).
authors.affiliation: Mortimer Market Centre, Central and North West London NHS Foundation Trust, London, United Kingdom Research Department of Infection and Population Health, University College London, London, United Kingdom b.sultan@ucl.ac.uk.
authors.forename: B
authors.initials: B
authors.lastname: Sultan
authors.affiliation: Department of Genitourinary Medicine, Guy's and St. Thomas' NHS Foundation Trust, London, United Kingdom.
authors.forename: J A
authors.initials: JA
authors.lastname: White
authors.affiliation: Mortimer Market Centre, Central and North West London NHS Foundation Trust, London, United Kingdom.
authors.forename: R
authors.initials: R
authors.lastname: Fish
authors.affiliation: Research Department of Infection and Population Health, University College London, London, United Kingdom.
authors.forename: G
authors.initials: G
authors.lastname: Carrick
authors.affiliation: Research Department of Infection and Population Health, University College London, London, United Kingdom.
authors.forename: N
authors.initials: N
authors.lastname: Brima
authors.affiliation: Research Department of Infection and Population Health, University College London, London, United Kingdom.
authors.forename: A
authors.initials: A
authors.lastname: Copas
authors.affiliation: Mortimer Market Centre, Central and North West London NHS Foundation Trust, London, United Kingdom.
authors.forename: A
authors.initials: A
authors.lastname: Robinson
authors.affiliation: Mortimer Market Centre, Central and North West London NHS Foundation Trust, London, United Kingdom Research Department of Infection and Population Health, University College London, London, United Kingdom.
authors.forename: R
authors.initials: R
authors.lastname: Gilson
authors.affiliation: Mortimer Market Centre, Central and North West London NHS Foundation Trust, London, United Kingdom Research Department of Infection and Population Health, University College London, London, United Kingdom.
authors.forename: D
authors.initials: D
authors.lastname: Mercey
authors.affiliation: Mortimer Market Centre, Central and North West London NHS Foundation Trust, London, United Kingdom.
authors.forename: P
authors.initials: P
authors.lastname: Benn
mesh_terms: D000328:Adult; D015373:Bacterial Typing Techniques; D002690:Chlamydia Infections / Q000175:diagnosis / Q000453:epidemiology* / Q000382:microbiology*; D002692:Chlamydia trachomatis / Q000302:isolation & purification*; D060085:Coinfection; D006069:Gonorrhea / Q000175:diagnosis / Q000453:epidemiology* / Q000382:microbiology*; D015658:HIV Infections / Q000453:epidemiology; D018451:Homosexuality, Male; D006801:Humans; D008297:Male; D008875:Middle Aged; D009344:Neisseria gonorrhoeae / Q000302:isolation & purification*; D010614:Pharynx / Q000382:microbiology; D015995:Prevalence; D012007:Rectum / Q000382:microbiology; D012680:Sensitivity and Specificity; D012749:Sexually Transmitted Diseases / Q000175:diagnosis / Q000453:epidemiology / Q000382:microbiology; D014521:Urethra / Q000382:microbiology; D055815:Young Adult