Bacterial Vaginosis

Last Updated: 2020-08-07

Author(s): Anzengruber F., Navarini A.


Gardner 1955.

Gardnerella vaginalis infection, amine colpitis.

Imbalance of the vaginal flora in favour of obligatory anaerobic bacteria and Gardnerella vaginalis.

Common, up to 30% prevalence, in sex workers > 50%. 

Risk factors are changing sexual partners, regular vaginal showers, etc.

Sexually transmitted infection with Gardnerella vaginalis. The proliferation of gram-negative.

Vulvovaginitis and colpitis with serous, thin, homogeneously whitish (no white spots), discharge with fishy odour. Amines are formed by anaerobic bacteria and smell like spoiled fish. 

  • Medical history
    • Unprotected sexual intercourse?
    • Smelly, vaginal discharge?
  • Bact. Swab
  • Urethra smear?
    • Cultural evidence.
  • Observe diagnostic criteria, namely 3 out of 4: 
    1. thin, homogeneous discharge 
    2. high pH value > 4.5 (normally the vagina is rather acidic, think of Döderlein bacteria) 
    3. 10 % KOH on a sample of the effluent leads to an increased fish smell
    4. > 20% of the cells are "Clue-Cells

Vulva, especially vagina.

  • Chronic inflammation in the vaginal area can promote HIV infection.
  • The risk of premature birth is 2 to 4 times higher.


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