Evaluation of vaginal introital sampling as an alternative approach for the detection of genital Chlamydia trachomatis infection in women.

BACKGROUND: Genital Chlamydia trachomatis infections in women are traditionally detected by testing cervical and urethral samples. This sampling approach is not acceptable in some, e.g. screening situations. We evaluate an alternative approach, i.e. use of vaginal self-collected specimen for testing by polymerase chain reaction.
METHODS: The sensitivity of self-collected vaginal (introital) samples to diagnose genital infections by Chlamydia trachomatis using Roche AMPLICOR CT/NG PCR was compared with the cervical- and first-voided urine samples from women consulting with- (Group 1; n=123) and without (Group 0; n=160) genital symptoms. Women were interviewed regarding genital hygiene. Genital symptoms and signs were noted.
RESULTS: C. trachomatis DNA was detected in 13.0% of women from Group 1 and in 5.0% of women from Group 0, i.e. in urine of 6.5% vs. 1.9%, in the cervical swab in 9.8% vs. 5.0% and in vaginal swab in 11.4% vs. 3.8% of women, respectively. The vaginal sample was the most sensitive specimen for detecting C. trachomatis in the Group 1 women. It had sensitivity of 87.5% vs. 75% for cervical- and 50% for urine specimens. In Group 0, the cervical sample was 100% sensitive, while the vaginal introital sample and urine had a sensitivity of 75% and 37.5%, respectively. C. trachomatis was less often detected in urine of women who routinely practised genital washing.
CONCLUSIONS: Vaginal sampling performed by the woman herself is a sensitive approach and might serve as an important stimulus for screening for C. trachomatis infections in young women at risk.