Final answer:
The diagnosis of bacterial vaginosis is made using Amsel's diagnostic criteria which requires at least three out of four characteristics: a white to yellow discharge, a fishy odor with 10% KOH, pH greater than 4.5, and the presence of clue cells. A Gram stain of a vaginal smear is also instrumental in differentiating bacterial vaginosis from other forms of vaginitis such as candidiasis.
Step-by-step explanation:
The clinical criteria for the diagnosis of bacterial vaginosis (BV) involves the assessment of vaginal fluids. According to Amsel's diagnostic criteria, a diagnosis is made when at least three out of the following four characteristics are present:
- A white to yellow vaginal discharge;
- A fishy odor, which becomes more noticeable when 10% KOH is added;
- A vaginal pH greater than 4.5;
- The presence of clue cells in the vaginal smear.
Direct examination of vaginal secretions is key for a diagnosis of vaginitis generally, and particularly for BV, as this allows for differentiation between various conditions such as candidiasis. The Gram stain of a vaginal smear is also used to evaluate the bacterial morphology, looking for a shift from gram-positive lactobacilli to gram-negative bacteria that are typically associated with BV.