Gardnerella

G.vaginalis

Gardnerella is a genus of bacteria that is primarily associated with bacterial vaginosis (BV) in women. This condition is characterized by an imbalance in the vaginal microbiota, leading to symptoms such as increased vaginal discharge and an unpleasant odor. Gardnerella is not the sole cause of BV but plays a significant role in the complex ecology of the vagina that leads to this condition.

Characteristics

Gardnerella bacteria are small, facultatively anaerobic, and non-motile. They are gram-variable, meaning they do not consistently stain as gram-positive or gram-negative. This is due to the structural characteristics of their cell walls. Gardnerella vaginalis is the most well-known species within this genus and was previously classified under the genus Haemophilus as Haemophilus vaginalis.

Pathogenesis

The pathogenesis of Gardnerella involves the adherence of the bacteria to the vaginal epithelial cells, which is facilitated by the production of a biofilm. This biofilm protects the bacteria from the host's immune response and allows for the colonization of other anaerobic bacteria, contributing to the symptoms of BV. The presence of Gardnerella is also associated with an increase in the vaginal pH, further disrupting the normal vaginal flora.

Clinical Significance

Gardnerella is primarily known for its role in bacterial vaginosis, which is the most common vaginal infection in women of reproductive age. While BV can sometimes resolve on its own, it can lead to more serious health issues, including increased susceptibility to sexually transmitted infections (STIs) and complications during pregnancy. Diagnosis of BV often involves the Amsel criteria or Nugent scoring, which include the presence of clue cells (vaginal epithelial cells covered with bacteria), a fishy odor, and a vaginal pH greater than 4.5.

Treatment

The treatment for bacterial vaginosis typically involves antibiotics, such as metronidazole or clindamycin. It is important to complete the full course of antibiotics to ensure the infection is fully cleared and to reduce the risk of recurrence. In some cases, probiotics may be recommended to help restore the normal vaginal flora.

Prevention

Preventative measures for BV include practicing good hygiene, avoiding douching, and using protection during sexual activity. Maintaining a healthy balance of bacteria in the vagina is key to preventing the overgrowth of Gardnerella and the development of BV.