Features of diagnostic methods for detection of T. vaginalis
Assay | Time to result | Equipment requirements | Sample type(s) | Cotesting option(s) | Relative costa | Relative sensitivityb | Comment(s) |
---|---|---|---|---|---|---|---|
Wet preparation microscopy | 5 min | Microscope with 40× objective | Clinician-obtained vaginal swabs | Bacterial vaginosis clue cells | $ | + | Trichomonads must be motile to avoid confusion with lymphocytes; motility decreases rapidly following sample collection |
OSOM | 15 min | None | Clinician-obtained vaginal swabs | None | $$ | +++ | CLIA waived—true POC test |
Culture | 1–7 days | Incubator, microscope with 40× objective | Clinician-obtained vaginal swabs | None | $$ | ++ | CIA moderate |
Affirm VPIII | <1 h | Affirm VPIII instrument | Clinician-obtained vaginal swabs | Gardnerella vaginalis, Candida albicans | $$ | ++ | Cannot be used for asymptomatic screening; CLIA moderate complexity, DNA probe technology |
AmpliVue | <1 h | AmpliVue instrument | Clinician-obtained vaginal swabs | None | $$ | ++ | CLIA moderate complexity, DNA amplification; no comparisons to NAATs available |
Hologic ATV | <8 h | Tigris or Panther automated system | Clinician-obtained vaginal swabs, endocervical swabs, or endocervical samples in PreservCyt medium; female urine on Tigris system only | Chlamydia/gonorrhea | $$$ | ++++ | CLIA high complexity, RNA amplification |
BD TVQ | <8 h | BD Viper XTR automated instrument | Female urine, patient-obtained vaginal swabs, endocervical swabs | Chlamydia/gonorrhea | $$$ | ++++ | CLIA high complexity, DNA amplification |
Cepheid | 60–90 min | GeneXpert instrument (variable module numbers available) | Patient-obtained vaginal swabs, endocervical swabs, female and male urine specimens | Chlamydia/gonorrhea | $$$$ | ++++ | CLIA moderate complexity, DNA amplification; pending FDA approval for use in United States |
↵a Costs vary by location and laboratory testing volume. Relative costs are shown as higher or lower (more or fewer dollar signs) than other tests, assuming that all factors are equal.
↵b Published sensitivity estimates may be misleading since those estimates are dependent on the sensitivity of the comparator assays. Assays compared only to microscopy or culture may have a high sensitivity estimate, but the estimate compared to a NAAT may be substantially lower. Thus, relative performance is shown here with more plus signs indicating higher sensitivity.