The use of vaginal wet smear: can we predict Mycoplasmas/Ureaplasmas?

Purpose: To evaluate the agreement of wet smear microscopy with Gram stain microscopy and to assess whether it is possible to predict Mycoplasmas/Ureaplasmas when analysing vaginal secretion with Gram stain and wet smear microscopy.

Methods: Women with complaints of the abnormal vaginal discharge were invited to participate. A sample of vaginal secretion was taken for wet smear microscopy and for Gram staining analysis. A sample from the endocervical canal was taken for DNA detection of seven infections: Mycoplasma hominis, Mycoplasma genitalium, Ureaplasma parvum, Ureaplasma urealyticum, Chlamydia trachomatis, Neisseria gonorrhoeae and Trichomonas vaginalis. The percentage agreement between wet smear and Gram stain was determined and the Cohen's Kappa values were calculated.

Results: Of 158 consecutive women included, one (or a few) of the infections were detected in 54% of them and the most frequent infection was Ureaplasma parvum (79% of all the cases with infections). The percentage agreement between vaginal wet smear and Gram stain was 73% (Cohen's Kappa value 0.63). A statistically significant association between the DNA detected Mycoplasmas/Ureaplasmas and bacterial vaginosis was found (positive amine test p = 0.046, wet smear p = 0.005 and Gram stain p = 0.03).

Conclusions: There was a statistically significant association between bacterial vaginosis and the DNA detected Mycoplasmas/Ureaplasmas. The agreement of vaginal wet smear with Gram stain was good.