II. Labs: Microscopy
- See Vaginal pH
- See Cervicitis
- See Sexually Transmitted Infection for complete genitourinary testing
- Patient collected samples
- Patient collected samples appear to be as accurate as those collected by clinicians
- Instruct patients to insert swab at least one inch into vagina
- Strauss (2005) Infect Dis Obstet Gynecol 13(1): 31-5 [PubMed]
- Normal
- Few Polymorphonuclear Leukocytes (PMNs)
- Vaginal epithelial cells
- KOH Preparation: Pseudo-hyphae or budding yeast
- Saline preparation (Wet Prep)
- Pear-shaped motile organisms: TrichomonasVaginitis
- Replaced with DNA Probe (see below)
- Poor Test Sensitivity: 50-65%
- Sample must be viewed soon after collection (Trichomonas loses motility with delay)
- Clue Cells: Bacterial Vaginosis
- Numerous Leukocytes
- Desquamative Vaginitis (local irritant induced)
- Many White Blood Cells
- Parabasilar cells
- Pear-shaped motile organisms: TrichomonasVaginitis
III. Labs: Newer advanced screening
- DNA probe for Trichomonas
- Preferred over microscopy in symptomatic or high risk women
- Nucleic Acid Amplification Test (NAAT) Sensitivity: >95%
- Rapid swabs are also available, with Test Sensitivity 80-90%
- Multiple DNA Probe Test (e.g. BD Max Vaginal Panel, BD Affirm VPIII Microbial Identification Test)
- High Sensitivity for Bacterial Vaginosis, Trichomoniasis, and Vulvovaginal Candidiasis
- Some False Positives with Trichomoniasis
- Cost is significantly higher than Wet Prep (e.g. BD Max is $260 and Wet Prep $10 in 2023, U.S.)
- Much longer delay for results than saline prep
- BD Affirm requires 45 minutes to run
- BD Max is typically sent to larger lab with 24 hour turn around for results
- References
- Sialidase Activity
- Specific for gardnerella vaginalis
IV. References
- McCollum in Swadron (2022) EM:Rap 22(10): 16-8