Self-taken vaginal swabs versus clinician-taken for detection of candida and bacterial vaginosis: a case-control study in primary care.

backgroundVaginal discharge and vulvitis are common presenting symptoms in general practice. Few studies have specifically looked at the validity of self-taken low vulvovaginal swabs (LVS) for the diagnosis of vulvovaginal candidiasis (VVC) and bacterial vaginosis (BV).

aimTo assess if patient self-taken LVS are a valid alternative to clinician-taken high vaginal swabs (HVS) for the detection of VVC and BV. DESIGN AND

settingCase-control study with the patient acting as their own control in an urban sexual health centre in Newcastle upon Tyne, UK.

methodFemales aged 16-65 years attending with symptomatic vaginal discharge, vulval irritation, genital pain, and an offensive genital smell were recruited into the study. Participants took a self-taken LVS before vaginal examination, during which a clinician took an HVS (reference standard). Main outcome measures were the diagnosis of BV or VVC infection.

resultsA total of 104 females were enrolled. Of those, 45 were diagnosed with VVC and 26 with BV. The sensitivities of self-taken LVS for VVC and BV were 95.5% and 88.5% respectively. Cohen's κ coefficient showed 'strong agreement' for the detection of both VVC and BV. Vulval itching was the most common symptom associated with VVC (69%), whereas 50% of females diagnosed with BV presented with an offensive discharge. Both symptoms had poor positive predictive values (0.63 and 0.50, respectively).

conclusionSelf-taken LVS appears to be a valid alternative to clinician-taken HVS for detecting VVC and BV infections. Symptoms were found to be a poor indicator of underlying infection.