Amsel’s Diagnostic Criteria for Bacterial Vaginosis
In clinical practice, bacterial vaginosis is diagnosed by the presence of 3 out of 4 Amsel criteria:
1. Thin, homogenous or milky vaginal discharge
2. Vaginal pH greater than 4.5 (i.e. greater than normal)
3. Positive whiff test (fishy amine odor when 10 percent potassium hydroxide solution is added)
4. At least 20 percent clue cells (vaginal epithelial cells with borders obscured by adherent coccobacilli on wet-mount preparation or Gram stain).
Mnemonic for Amsel’s criteria
- Adherent bacteria. Clue cells are vaginal epithelial cells that have bacteria adherent to their surfaces. You need at least 20% clue cells.
- Milky discharge (from the vagina that is thin and homogeneous in nature)
- Stench (strong fishy odor) when 10% KOH is added. That’s the positive whiff test
- Elevated PH ( Vaginal pH greater than 4.5 (i.e. greater than normal))
- L.