A Scottish multi-centre service evaluation examining the prevalence and diagnosis of Trichomonas vaginalis in symptomatic women attending sexual health clinics.

Trichomoniasis caused by the protozoan parasite Trichomonas vaginalis (TV) is one of the most commonly occurring sexually transmitted infections of non-viral origin. This study examines the prevalence of TV infection amongst consenting symptomatic women attending three of the largest sexual health clinics in Scotland, United Kingdom. In addition, an evaluation of three testing methods to identify TV from vaginal fluid was performed involving the commercial Hologic APTIMA TV transcription-mediated amplification assay, a real-time PCR assay and microscopy. A total of 398 patients consented to participation and all were tested by the three methods. The prevalence of TV was 2.8% (n = 11), with both molecular assays correctly detecting an additional two cases of TV compared to microscopy. The prevalence of three other sexually transmitted pathogens, namely Chlamydia trachomatis, Neisseria gonorrhoeae and herpes simplex virus were 7.3% (n = 31), 0.3% (n = 1) and 1.5% (n = 6), respectively. The majority of TV cases (78%; n = 8) occurred in women greater than 29 years of age compared to most Chlamydia trachomatis cases, who were aged 30 or less (97%; n = 30).