Correlations of chlamydia and gonorrhoea among pharyngeal, rectal and urethral sites among Thai men who have sex with men: multicentre community-led test and treat cohort in Thailand.
OBJECTIVE
Routine screening for Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (NG) infections in sexually exposed anatomical sites may be challenging in resource-limited settings. The objective of this study was to determine the proportion of missed CT/NG diagnoses if a single anatomical site screening was performed among men who have sex with men (MSM) by examining the pattern of anatomical sites of CT/NG infections.


METHODS
Thai MSM were enrolled to the community-led test and treat cohort. Screening for CT/NG infections was performed from pharyngeal swab, rectal swab and urine using nucleic acid amplification testing. The correlations of CT/NG among the three anatomical sites were analysed.


RESULTS
Among 1610 MSM included in the analysis, 21.7% had CT and 15.5% had NG infection at any anatomical site. Among those tested negative for CT or NG infection at either pharyngeal, rectal or urethral site, 8%-19% had CT infection and 7%-12% had NG infection at the remaining two sites. Of the total 349 CT infections, 85.9%, 30.6% and 67.8% would have been missed if only pharyngeal, rectal or urethral screening was performed, respectively. Of the total 249 NG infection, 55.7%, 39.6% and 77.4% would have been missed if only pharyngeal, rectal or urethral screening was performed, respectively. The majority of each anatomical site of CT/NG infection was isolated to their respective site, with rectal site having the highest proportion of isolation: 78.9% of rectal CT and 62.7% of rectal NG infection.


CONCLUSIONS
A high proportion of CT/NG infections would be missed if single anatomical site screening was performed among MSM. All-site screening is highly recommended, but if not feasible, rectal screening provides the highest yield of CT/NG diagnoses. Effort in lowering the cost of the CT/NG screening test or developing affordable molecular technologies for CT/NG detection is needed for MSM in resource-limited settings.


TRIAL REGISTRATION NUMBER
NCT03580512; Results.
['Hiransuthikul|Akarin|A|0000-0003-1906-8171', 'Sungsing|Thanthip|T|', 'Jantarapakde|Jureeporn|J|', 'Trachunthong|Deondara|D|', 'Mills|Stephen|S|', 'Vannakit|Ravipa|R|', 'Phanuphak|Praphan|P|', 'Phanuphak|Nittaya|N|']
D000328:Adult D002690:Chlamydia Infections D003153:Community Health Services D003951:Diagnostic Errors D006069:Gonorrhea D018451:Homosexuality, Male D006801:Humans D008297:Male D010608:Pharyngeal Diseases D012002:Rectal Diseases D013785:Thailand D014522:Urethral Diseases
men who have sex with men chlamydia trachomatis neisseria gonorrhoeae