Which organism causes bacterial vaginosis, as indicated by the presence of 'clue cells' and a fishy odor?

Bacterial vaginosis is primarily associated with the overgrowth of certain bacteria in the vagina, and Gardnerella vaginalis is one of the key organisms involved in this condition. The term 'clue cells' refers to the vaginal epithelial cells that have a stippled appearance due to the presence of bacterial cells on their surface, which are commonly observed in cases of bacterial vaginosis. Additionally, the fishy odor that characterizes this condition is often particularly noticeable after sexual intercourse or during menstruation, and it is mainly attributed to the metabolic byproducts of Gardnerella vaginalis and other anaerobic bacteria that proliferate when the normal flora is disrupted.

In contrast, other organisms listed do not typically cause bacterial vaginosis. For example, Staphylococcus epidermidis is a skin commensal organism, and while it may be present in various infections, it is not associated with the symptoms of bacterial vaginosis. Streptococcus agalactiae, also known as Group B Streptococcus, is more commonly linked with neonatal infections and not with bacterial vaginosis. E. coli is primarily known for causing urinary tract infections and gastrointestinal illnesses, rather than the symptoms related to bacterial vaginosis. Therefore, Gardnerella vaginalis is correctly