Bacterial Vaginosis (BV)is the most common vaginal infection in women, affecting between 5% to 70% of women in the world. It is due to an imbalance of vaginal flora, with a decrease in helpful lactobacilli and an increase in the overall number of anaerobic bacteria. Historically, it was thought that Gardnerella was the only causative agent. But studies have now confirmed that it is due to the increase in normal vaginal bacteria.
Clinical Presentation of Bacterial Vaginosis
Women with BV mainly present to clinics with ‘bad-smelling’ vaginal discharge which gets stronger post-coitus. Other symptoms include dysuria, dyspareunia, and itching. It is important for a physician to take a detailed history and identify the presence of any risk factors like IUDs, STDS, vaginal douching, multiple sex partners or a female sex partner, recent antibiotic use, and smoking. Having multiple partners is considered a risk factor for BV but it is important to remember that BV is not a sexually transmitted infection.
Diagnosis of Bacterial Vaginosis
The definitive diagnosis of bacterial vaginosis depends on the presence of the triad; positive whiff test, clue cells on the wet mount, and vaginal pH higher than normal (greater than 4.5). Most doctors can diagnose BV if characteristic thin, whitish-gray discharge plus two out of the triad are found. If no discharge is present, the entire triad should be present for a definitive diagnosis to be made. However, clinical diagnosis is based on Amsel criteria, with 3 out of the total 4 criteria needing to be present for confirmation. The criteria are homogenous, milky-white secretions, vaginal pH greater than 4.5, clue cells on wet mount, and a fishy order when potassium hydroxide is added to discharge (positive whiff test).
Treatment of Bacterial Vaginosis
Most cases of bacterial vaginosis have been found to be self-limited. However, if treatment is needed, Clindamycin or metronidazole are the drugs of choice amongst clinicians. Added benefits of these drugs are that they are safe for use by pregnant women. Although, recent studies found that Clindamycin given after 22 weeks increases the risk of pre-term birth. No conclusive results have reached to support that claim.
Some women were found to not be treated with primary treatment, needing an added dose of antibiotics. Also, the recurrence rate of BV was found to be quite high. Clinicians usually prescribe a second dose of antibiotics in case of recurrent symptoms.
Complications of Bacterial Vaginosis
Bacterial Vaginosis, if left untreated, can lead to many unwanted consequences. Even though BV itself is not an STI, it can lead to an increased susceptibility to other STIs. Studies found an increased risk of chlamydia and gonorrhea infections in women with bacterial vaginosis. Also, it was found that BV increases the rate of HIV shedding, with studies proving that HIV-infected women with BV were more likely to transmit HIV than those without bacterial vaginosis. Researchers also found that If co-infection with HPV occurs, even asymptomatic bacterial vaginosis should be treated as it increases HPV persistence.
Studies on pregnant women with bacterial vaginosis found that if diagnosed in the first trimester, it can cause spontaneous abortions, and if in the second trimester, can lead to preterm labor. They also discovered the increased risk for premature rupture of membranes, chorioamnionitis, and postpartum endometritis in pregnant women.
Overall, the treatment of bacterial vaginosis and screening for other STIs with BV is very important to reduce morbidity. Also, screening for BV in pregnant women is recommended.