Vaginal Self-Swab vs Cervical for Diagnosis of Gonorrhea and Chlamydia
Assessment of self taken swabs versus clinician taken swab cultures for diagnosing gonorrhea in women: single centre, diagnostic accuracy study Assessment of best single sample for finding chlamydia in women with and without symptoms: a diagnostic test study
Schoeman, Stewart, et al. BMJ, December 2012.
The Idea: Is vulvovaginal self-swabbing as effective in diagnosing infection with chlamydia and gonorrhea as cervical swabbing from a speculum exam?
The Study: Each study had almost 4,000 women from a single health center who both self-swabbed and received a speculum exam with cervical swab. Rates of PCR amplification of GC and Chlam were compared from two samples
The Findings: Self-swabbing wins! The vulvovaginal self-swab was found to be superior to cervical swab, with a cervical swab alone missing 9% of infections, or 1 out of every 11 cases of chlamydia.
The takeaway: Vulvovaginal specimens are more sensitive for detection of GC and Chlam by PCR amplification than cervical swabbing alone. Remember to counsel on further testing for other STDs, such as syphilis, trichamonas and HIV.