Gardnerella

Gardnerella is a genus of gram-variable bacteria of which Gardnerella vaginalis is the only species. Gardnerella vaginalis can cause bacterial vaginosis in some women.

Additional recommended knowledge

How to ensure accurate weighing results every day?

Essential Laboratory Skills Guide

Daily Visual Balance Check

Once classified as a species of Haemophilus, G. vaginalis grows as small, circular, convex, gray colonies on chocolate agar; it will also grow on HBT agar. A selective medium for G. vaginalis is colistin-oxolinic acid blood agar.

While typically isolated in genital cultures, it may also be detected from other sources, such as blood, urine and pharynx. Although a chief cause of bacterial vaginosis, it may be isolated from women without any signs or symptoms of infection.

Under the microscope it appears as a gram-negative rod, although it has been reported to have a gram-positive cell wall. It is associated microscopically with clue cells, which are epithelial cells covered in bacteria.

Infections with G. vaginalis go along with proteolysis, giving nitrous products such as cadaverines and putrescines, which can cause a bad smell and loss of water. One method of treatment is metronidazole.