Detection of Trichomonas vaginalis on modified Columbia agar in the routine laboratory.

Broth culture of Trichomonas vaginalis is considered the "gold standard" for the diagnosis of trichomoniasis. Two studies were carried out to evaluate modified Columbia agar (MCA) for the isolation of T. vaginalis from clinical samples. Study I compared isolation on MCA to that on liquid medium with 889 vaginal samples. Out of 63 samples positive for T. vaginalis (7.1% of total), MCA identified 62 (98.4%) and broth identified 58 (92.1%). In study II, trichomoniasis was diagnosed within the scope of a screening program for a total of 39,585 men and women by culture on MCA and direct microscopy. Culture on MCA detected 199 (98.5%) and Gram staining detected 163 (80.7%) of 202 positive specimens. Wet-mount preparations used for symptomatic patients identified 103 (92.8%) of 111 cases. Culture of T. vaginalis from clinical samples on MCA is highly sensitive and reliable, as well as timesaving, and therefore suitable for screening of symptomatic and asymptomatic individuals.