Vaginal panel assay helps vaginitis patients get accurate diagnosis

An assay that detects DNA associated with bacterial vaginosis, vulvovaginal candidiasis, and Trichomonas vaginalis helps women get an accurate diagnosis, which in turn facilitates appropriate and timely treatment, according to a study.

The assay determines whether a vaginal swab sample is positive or negative for bacterial vaginosis, Candida group, and T. vaginalis. It uses a bioinformatics algorithm that detects the presence, absence, and relative load of disease markers.

In the study, researchers collected vaginal swab samples from 489 women (median age 30 years) with vaginitis symptoms. They performed the assay in a separate testing site.

Of the 469 evaluable specimens, 467 yielded reportable results for bacterial vaginosis and 466 yielded reportable results for both vulvovaginal candidiasis and T. vaginalis. The most common symptom was abnormal vaginal discharge (70.8 percent), followed by vaginal itching and burning or irritation (56.5 percent).

Clinical diagnosis with the vaginal panel assay had a positive percent agreement of 57.9 percent for bacterial vaginosis, 53.5 percent for vulvovaginal candidiasis, and 28.0 percent for T vaginalis, respectively. The corresponding negative percent agreement values for clinical diagnosis of the respective gynaecological conditions were 80.2 percent, 77.0 percent, and 99.8 percent.

Sixty-five percent (67/103), 44 percent (26/59), and 56 percent (10/18) of women identified as having bacterial vaginosis, vulvovaginal candidiasis, and T. vaginalis by assay, respectively, received no treatment for vaginitis based on a negative clinical diagnosis.

Compared with the assay, clinical diagnosis had false positive rates of 19.8 percent for bacterial vaginosis, 23.0 percent for vulvovaginal candidiasis, and 0.2 percent for T. vaginalis. There were significant differences in paired proportions between the vaginal panel assay and clinical diagnosis for the detection of bacterial vaginosis and T. vaginalis.