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The objective of this study was to measure the performance of the Affirm Ambient Temperature Transport System (ATTS) over time and to estimate the length of time the system can preserve a vaginal specimen containing the three common organisms causing vaginitis: Trichomonas vaginalis, Candida species, and Gardnerella vaginalis (one of the causative agents of bacterial vaginosis). Women with symptoms of vaginitis presenting to one of three clinical centers were evaluated over a 4- to 8-week period. Four simultaneously obtained swabs were collected and tested by the Affirm VPIII assay at time zero with and without a preservative reagent, at 24 h with reagent, and at either 48 or 72 h with reagent. For each of the three organisms, Trichomonas, Gardnerella, and Candida, positivity at each time point was evaluated and compared to that at reference time zero with and without the ATTS. A total of 940 specimens were obtained from the three clinical sites. Eight hundred three were positive for one or more of the three organisms. Gardnerella had the highest overall positive rate (62%), followed by Candida with 18% and Trichomonas at 9%. The percent sensitivity versus control for Trichomonas ranged from 100% at time zero with and without reagent to 91% by 72 h. Gardnerella and Candida sensitivity remained at 100% for each time period. The Affirm VPIII ATTS system performed within 10% of the control swab (no transport reagent) at all four time points (0, 24, 48, and 72 h) for Trichomonas, Gardnerella, and Candida.

A new self-contained medium system for the cultivation of Neisseria gonorrhoeae was compared to modified Thayer-Martin medium for the diagnosis of gonorrhea from endocervical specimens. There was no difference in the ability of the two methods to support the growth of N. gonorrhoeae.

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.

A comparison of delayed versus immediate inoculation of culture medium for the diagnosis of trichomonosis was conducted. The sensitivities of the two methods were 100 and 97.4%, respectively. Delayed inoculation of culture medium for women without evidence of trichomonosis on direct microscopic examination is a valid diagnostic procedure.