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Vaginal Discharge Testing

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Vaginal Discharge Testing, Vaginal Discharge Microscopy, Vaginal Discharge DNA Probe, Wet Prep, Vaginal KOH Preparation

  • See Also
  1. KOH Preparation
  2. Vaginal pH
  3. Gonorrhea PCR
  4. Chlamydia PCR
  • Labs
  • Microscopy
  1. See Vaginal pH
  2. See Cervicitis
  3. See Sexually Transmitted Infection for complete genitourinary testing
  4. Patient collected samples
    1. Patient collected samples appear to be as accurate as those collected by clinicians
    2. Instruct patients to insert swab at least one inch into vagina
    3. Strauss (2005) Infect Dis Obstet Gynecol 13(1): 31-5 [PubMed]
  5. Normal
    1. Few Polymorphonuclear Leukocytes (PMNs)
    2. Vaginal epithelial cells
  6. KOH Preparation: Pseudo-hyphae or budding yeast
    1. Candida Vulvovaginitis
  7. Saline preparation (Wet Prep)
    1. Pear-shaped motile organisms: TrichomonasVaginitis
      1. Replaced with DNA Probe (see below)
      2. Poor Test Sensitivity: 50-65%
      3. Sample must be viewed soon after collection (Trichomonas loses motility with delay)
    2. Clue Cells: Bacterial Vaginosis
    3. Numerous Leukocytes
      1. TrichomonasVaginitis
      2. Gonorrhea
      3. Chlamydia
    4. Desquamative Vaginitis (local irritant induced)
      1. Many White Blood Cells
      2. Parabasilar cells
  • Labs
  • Newer advanced screening
  1. DNA probe for Trichomonas
    1. Preferred over microscopy in symptomatic or high risk women
    2. Nucleic Acid Amplification Test (NAAT) Sensitivity: >95%
    3. Rapid swabs are also available, with Test Sensitivity 80-90%
  2. Multiple DNA Probe Test (e.g. BD Max Vaginal Panel, BD Affirm VPIII Microbial Identification Test)
    1. High Sensitivity for Bacterial Vaginosis, Trichomoniasis, and Vulvovaginal Candidiasis
    2. Some False Positives with Trichomoniasis
    3. Cost is significantly higher than Wet Prep (e.g. BD Max is $260 and Wet Prep $10 in 2023, U.S.)
    4. Much longer delay for results than saline prep
      1. BD Affirm requires 45 minutes to run
      2. BD Max is typically sent to larger lab with 24 hour turn around for results
    5. References
      1. Barry (2023) Am Fam Physician 108(3): 309-10 [PubMed]
  3. Sialidase Activity
    1. Specific for gardnerella vaginalis
  • References
  1. McCollum in Swadron (2022) EM:Rap 22(10): 16-8