Detection of Trichomonosis in Vaginal and Urine Specimens from Women by Culture and PCR

Abstract

Vaginal trichomonosis is a highly prevalent infection which has been associated with human immunodeficiency virus acquisition and preterm birth. Culture is the current “gold standard” for diagnosis. As urine-based testing using DNA amplification techniques becomes more widely used for other sexually transmitted diseases (STDs) such as gonorrhea and chlamydia, a similar technique for trichomonosis would be highly desirable. Women attending an STD clinic for a new complaint were screened for Trichomonas vaginalis by wet-preparation (wet-prep) microscopy and culture and for the presence of T. vaginalis DNA by specific PCR of vaginal and urine specimens. The presence of trichomonosis was defined as the detection of T. vaginalis by direct microscopy and/or culture from either vaginal samples or urine. The overall prevalence of trichomonosis in the population was 28% (53 of 190). The sensitivity and specificity of PCR using vaginal samples were 89 and 97%, respectively. Seventy-four percent (38 of 51) of women who had a vaginal wet prep or vaginal culture positive for trichomonads had microscopic and/or culture evidence of the organisms in the urine. Two women were positive for trichomonads by wet prep or culture only in the urine. The sensitivity and specificity of PCR using urine specimens were 64 and 100%, respectively. These results indicate that the exclusive use of urine-based detection of T. vaginalis is not appropriate in women. PCR-based detection of T. vaginalis using vaginal specimens may provide an alternative to culture.

The use of modified Field’s stain in diagnosis of Trichomonas vaginalis

“…There was significant association between trichomoniasis and the presence of malodor and discharge (p= < 0.05). Similar reports found by Lawing et al [20] and Swygard et al [21] who reported seventy-five percent (57%) of women with trichomoniasis complained of vaginal symptoms such as discharge, malodour, and itching. The presence of these symptoms was not significantly associated with a positive T. vaginalis infections (P= 0.47).…”

Diagnosis and molecular characterization ofTrichomonas vaginalisin sex workers in the Philippines

“…DNA was extracted according to the procedure of Rivera et al 11 PCR reaction mixture and amplification condition procedures using three primer sets: the universal trichomonad primer set TFR1/2, 12 and the species-specific primer sets TVK3/7, [13][14][15] and TV1/2 16 were followed according to the manufacturer's instructions (New England BioLabs, Ipswich, MA, USA) in TC-412 thermocycler (Techne, Cambridge, UK). PCR mixture without DNA from samples was used as the negative control.…”

Guidelines for the laboratory diagnosis of trichomoniasis in East European countries

“…[42][43][44] Similarly, the specificity of wet-mount microscopy is generally high, whereas its sensitivity, compared with PCRs is poor, with reported rates ranging from 34% to 58%. [44][45][46][47][48] A few recent studies describe the application of real-time PCR for the diagnosis of trichomoniasis. 34,[49][50][51][52] However, the application of in-house NAATs for the diagnosis of individual cases of trichomoniasis in routine practice is possible only after complete validation of the method.…”