From the Guidelines
Gardnerella vaginalis infection, also known as bacterial vaginosis (BV), should be treated with metronidazole 250 mg orally three times a day for 7 days, as recommended by the Centers for Disease Control and Prevention 1.
Diagnosis and Treatment
The diagnosis of BV is typically made by fulfilling 3 of 4 criteria: vaginal pH greater than 4.7, the presence of clue cells on wet mount, thin homogeneous discharge, and amine “fishy odor” when potassium hydroxide is added to the discharge 1.
- Symptoms of BV include thin, grayish-white vaginal discharge with a fishy odor, particularly noticeable after intercourse, though many women remain asymptomatic.
- The principal goal of therapy for BV is to relieve vaginal symptoms and signs of infection, regardless of pregnancy status 1.
- Treatment options include:
- Metronidazole 250 mg orally three times a day for 7 days
- Alternative regimens: metronidazole 2 g orally in a single dose or clindamycin 300 mg orally twice a day for 7 days 1
- For pregnant women, treatment is recommended to reduce the risk of premature rupture of the membranes, preterm labor, and preterm birth 1.
Prevention and Recurrence
- Maintaining vaginal pH balance through proper hygiene and avoiding douching can help prevent recurrence.
- Treatment of the male sex partner has not been beneficial in preventing the recurrence of BV 1.
- Follow-up visits are unnecessary if symptoms resolve, but recurrence is not unusual and patients should return for additional treatment if symptoms recur 1.
From the FDA Drug Label
A randomized, double-blind, placebo-controlled clinical trial in 235 non-pregnant women was conducted to evaluate the efficacy of tinidazole for the treatment of bacterial vaginosis. A clinical diagnosis of bacterial vaginosis was based on Amsel's criteria and defined by the presence of an abnormal homogeneous vaginal discharge that (a) has a pH of greater than 4. 5, (b) emits a "fishy" amine odor when mixed with a 10% KOH solution, and (c) contains ≥20% clue cells on microscopic examination. Therapeutic cure was a composite endpoint, consisting of both a clinical cure and microbiologic cure In patients with all four Amsel's criteria and with a baseline Nugent score ≥4, tinidazole oral tablets given as either 2 g once daily for 2 days or 1 g once daily for 5 days demonstrated superior efficacy over placebo tablets as measured by therapeutic cure, clinical cure, and a microbiologic cure.
The diagnosis of Gardnerella vaginalis (Bacterial Vaginosis) infection is based on:
- Amsel's criteria: abnormal homogeneous vaginal discharge with a pH of greater than 4.5, "fishy" amine odor when mixed with a 10% KOH solution, and ≥20% clue cells on microscopic examination
- Nugent score: a score ≥4 on Gram stain of the vaginal smear The treatment for Gardnerella vaginalis (Bacterial Vaginosis) infection is:
- Tinidazole: 2 g once daily for 2 days or 1 g once daily for 5 days, which demonstrated superior efficacy over placebo in a randomized, double-blind, placebo-controlled clinical trial 2
From the Research
Diagnosis of Gardnerella Vaginalis Infection
- The diagnosis of Gardnerella vaginalis infection, also known as bacterial vaginosis, can be made using traditional clinical and laboratory methods, including vaginal saline wet prep, potassium hydroxide microscopic examinations, Gram's stain, and pH tests 3.
- A DNA probe test can also be used to diagnose Gardnerella vaginalis infection, and it has been shown to be more sensitive than traditional methods in detecting the presence of the bacteria after treatment 3.
- The diagnosis of bacterial vaginosis is typically made based on the presence of four clinical criteria, including a thin, white, yellowish, homogeneous vaginal discharge, a pH of vaginal fluid greater than 4.5, a positive whiff test, and the presence of clue cells on microscopic examination 4.
Treatment of Gardnerella Vaginalis Infection
- The treatment of Gardnerella vaginalis infection typically involves the use of antimicrobial agents, such as metronidazole, clindamycin, and tinidazole 3, 5, 4, 6, 7.
- Metronidazole is currently the first-line drug of choice for the treatment of Gardnerella vaginalis infection, and it can be administered orally, parenterally, or intravaginally as a gel or sponge 3, 7.
- Clindamycin is also effective in treating Gardnerella vaginalis infection, and it can be administered orally or intravaginally as a cream 3, 5.
- Tinidazole is another option for the treatment of Gardnerella vaginalis infection, and it has been shown to be equivalent to metronidazole in efficacy, with a more favorable side effect profile 6.
- The treatment of recurrent Gardnerella vaginalis infection may involve an extended course of metronidazole treatment, or the use of alternative agents such as clindamycin or tinidazole 4.
Treatment Outcomes and Recurrence
- The cure rates for Gardnerella vaginalis infection using metronidazole, clindamycin, and tinidazole are generally high, ranging from 75% to 90% 3, 5, 6.
- However, recurrence of Gardnerella vaginalis infection is common, with up to 50% of women experiencing recurrence within one year of treatment 4.
- The recurrence of Gardnerella vaginalis infection may be due to the persistence of residual infection, resistance, or reinfection from male or female partners 4.
- The use of probiotics, prebiotics, and botanical treatments has shown some promise in preventing recurrence, but further studies are needed to confirm their effectiveness 4.