High burden of chlamydia and gonorrhoea in pharyngeal, rectal and urethral sites among Thai transgender women: implications for anatomical site selection for the screening of STI

Sex Transm Infect. 2019 Nov;95(7):534-539. doi: 10.1136/sextrans-2018-053835. Epub 2019 Apr 13.

Abstract

Objective: Comprehensive data on Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (NG) infections to guide screening services among transgender women (TGW) are limited. We studied the burden of CT/NG infections in pharyngeal, rectal and urethral sites of Thai TGW and determined missed CT/NG diagnoses if selected site screening was performed.

Methods: Thai TGW were enrolled to the community-led test and treat cohort. CT/NG screening was performed from pharyngeal swab, rectal swab and urine using nucleic acid amplification test. CT/NG prevalence in each anatomical site was analysed, along with the relationships of CT/NG among the three anatomical sites.

Results: Of 764 TGW included in the analysis, 232 (30.4%) had CT/NG infections at any anatomical site, with an overall incidence of 23.7 per 100 person-years. The most common CT/NG infections by anatomical site were rectal CT (19.5%), rectal NG (9.6%) and pharyngeal NG (8.1%). Among 232 TGW with CT/NG infections at any anatomical site, 22%-94.4% of infections would have been missed if single anatomical site testing was conducted, depending on the selected site. Among 668 TGW who tested negative at pharyngeal site, 20.4% had either rectal or urethral infections. Among 583 TGW who tested negative at the rectal site, 8.7% had either pharyngeal or urethral infections. Among 751 TGW who tested negative at the urethral site, 19.2% had either pharyngeal or rectal infections.

Conclusion: Almost one-third of Thai TGW had CT/NG infections. All-site screening is highly recommended to identify these infections, but if not feasible rectal screening provides the highest yield of CT/NG diagnoses. Affordable molecular technologies and/or CT/NG screening in pooled samples from different anatomical sites are urgently needed.

Trial registration number: NCT03580512.

Keywords: chlamydia trachomatis; hiv; neisseria gonorrhoea; transsexual.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Adolescent
  • Adult
  • Asian People
  • Chlamydia / isolation & purification
  • Chlamydia Infections / epidemiology*
  • Female
  • Gonorrhea / epidemiology*
  • Humans
  • Male
  • Mass Screening
  • Middle Aged
  • Neisseria gonorrhoeae / isolation & purification
  • Pharynx / microbiology*
  • Prevalence
  • Rectum / microbiology*
  • Thailand / epidemiology
  • Transgender Persons*
  • Urethra / microbiology*
  • Young Adult

Associated data

  • ClinicalTrials.gov/NCT03580512