The Amsel's criteria are a set of four clinical features used to diagnose bacterial vaginosis (BV), a common vaginal condition. This set of criteria was first published in 1983 in the American Journal of Medicine by Dr. Ronald Amsel.
What are the Amsel's criteria?
The Amsel's criteria include:
- Homogenous, thin, white or gray vaginal discharge: This discharge is usually described as "fishy" or "musty" smelling.
- Vaginal pH greater than 4.5: This can be measured using a pH paper strip.
- Positive whiff test: A fishy amine odor is released when a drop of potassium hydroxide (KOH) is added to the vaginal discharge.
- Presence of clue cells on a wet mount: Clue cells are epithelial cells covered in bacteria, making them appear "stippled" or "granular" under a microscope.
How are the Amsel's criteria used?
For a diagnosis of bacterial vaginosis using Amsel's criteria, at least three of the four criteria must be present.
When are Amsel's criteria used?
Amsel's criteria are often used in clinical settings to quickly and easily assess for bacterial vaginosis. However, it's important to note that:
- The sensitivity and specificity of Amsel's criteria are not perfect.
- Some women with bacterial vaginosis may not meet all four criteria.
- Other tests, such as the Nugent score, might be used for a more accurate diagnosis.
What are the limitations of Amsel's criteria?
- Subjectivity: The assessment of vaginal discharge and odor can be subjective, leading to inconsistencies in diagnosis.
- False negatives: Some women with bacterial vaginosis might not show all four criteria, leading to false negative results.
- False positives: Other conditions can cause similar symptoms, potentially leading to a misdiagnosis of bacterial vaginosis.
