Comprehensive Molecular Screening in a Cohort of Young Men Who Have Sex with Men and Transgender Women: Effect of Additive Rectal Specimen Source Collection and Analyte Testing

BACKGROUND This study's purposes were to characterize detection rates of several sexually transmitted infection (STI) agents and describe the effect additional specimen source and analyte screening has on STI detection within a cohort of young men who have sex with men and transgender women. METHODS Within a 16-month interval, 1966 encounters involved dual urine and rectal swab submissions assessed by commercial transcription-mediated amplification-based assays for Chlamydia trachomatis and Neisseria gonorrhoeae and by off-label transcription-mediated amplification-based Trichomonas vaginalis and Mycoplasma genitalium testing. Identification of STI carriers used algorithms involving Food and Drug Administration-cleared screening methods, laboratory-modified testing for extraurogenital C. trachomatis and N. gonorrhoeae, and laboratory-developed tests for T. vaginalis and M. genitalium. RESULTS Food and Drug Administration-indicated urine C. trachomatis and N. gonorrhoeae screening revealed 39 encounters (2.0%) yielding one or both agents. Via C. trachomatis and N. gonorrhoeae screening that included rectal swab analysis, 264 encounters (13.4%) yielded evidence of either (140 C. trachomatis, 88 N. gonorrhoeae) or both (36 participants) infections. Detection rates for C. trachomatis and N. gonorrhoeae were 1.4% and 0.6% for urine screening and 8.2% and 6.2% for rectal screening, respectively. Off-label screening identified 413 additional encounters with STI (5 T. vaginalis, 396 M. genitalium, 12 with both). Of these identifications, 82.1% were generated from analysis of rectal swabs (4 participants with T. vaginalis, 323 participants with M. genitalium, 12 with both). Overall detection rates of T. vaginalis (0.2% urine, 1.3% rectal) and M. genitalium (9.1% urine, 21.5% rectal) were variable. CONCLUSIONS Additive analyte testing, including extraurogenital collections, contributes to comprehensive STI screening within a high-risk demographic.