Gardnerella vaginalis (Bacterial Vaginosis)


Gardnerella vaginalis 

  • Characteristics
    • Gram-variable rod
    • Facultative anaerobe 
  • Transmission/risk factors 
    • Vaginal douching
      • Disturbs the vaginal microflora, resulting in overgrowth of Gardnerella
    • Use of antibiotics
      • Also disrupts vaginal flora, creating open niche for Gardnerella
    • Immunosuppression
    • Not sexually transmitted disease
      • However, associated with sexual activity
      • Multiple sex partners or unprotected sex
  • Disease: bacterial vaginosis
    • Gray vaginal discharge with “fishy” odor
    • Nonpainful (no vaginal inflammation)
  • Diagnosis
    • Clue cells on wet mount microscopy 
      • Vaginal squamous epithelial cells covered with Gardnerella
        • Stippled appearance along outer margin
    • Vaginal pH >4.5 
    • Whiff test (KOH)
      • Mixing discharge with KOH increases fishy odor
      • Odor produced by volatile amines produced by Gardnerella
  • Treatment
    • Metronidazole or clindamycin