Better Diagnostic Method for Bacterial Vaginosis

There is a simpler and more affordable molecular test that shows the reduction of the genus Lactobacillus and an increased species variety of vaginal microbiota. This test can function as a practical substitute investigative method for the assessment of bacterial vaginosis (BV).

BV occurs when the vaginal microbiota is in an abnormal state characterized by a reduction of lactobacilli, increased variety of the bacterial population and an elevated pH. BV is among the most common vaginal conditions in fertile, pregnant and premenopausal women.

Most people found to have BV will normally have consulted a doctor due to vaginal malodour. However, a patient can also suffer from BV without malodor or other visible signs and symptoms.

BV High Recurrence Rates and Treatment Failure

Some of the issues of BV that plagues doctors are high recurrence rates and treatment failure. This makes it necessary to develop a new and better treatment for BV. This requires identification of universal markers that are based on molecular methods.

A group of researchers from Netherlands, led by Joke A. M. Dols, conducted a study aiming to evaluate the vaginal microbiota sequencing of women who test negative and positive for BV so as to confirm the composition of bacterial populations that are associated with BV.

The researchers used a population of 40 adult women who had vaginal signs or symptoms, those that had been asked to go for STD testing or those who required an STD test because a sexual partner had a proven STI. Samples from the study subjects were collected in June and July 2012. 20 of these tested negative to BV and 20 tested positive.

Sample collection involved removing abundant mucus using a cotton swab and a standard cervical examination was performed. Another sample was also collected to test for Neisseria gonorrhoeae and Chlamydia trachomatis.

Out of the 20 BV-negative women, 18 were of European or Asian origin and 2 were of a Hispanic background. From the BV-positive population, 9 were of European or Asian origin and 11 were of a Hispanic background.

Out of the 40 women, two of them tested positive for VVC. 10 of the 40 women studied had STD. The most common STI among the 10 was C. trachomatis. No one studied tested positive to HIV, Gonorrhoea, Syphilis, Hepatitis B, Scabies, Moluscum contagiosum, PID or genito-ulcerative disease.

BV Bacterial Population Clusters

The study found that there are two clusters of bacterial populations in BV negative women. These clusters are dominated by either Lactobacillus crispatus or Lactobacillus iners. As for BV positive women, there are three distinct clusters.

The study also found that L. crispatus is not the only one responsible for keeping a BV negative state and is displaced when BV occurs in the woman. The researchers concluded that an overall increased variety of bacterial species in combination with a depletion of the genus Lactobacillus are good universal molecular markers to diagnosis BV correctly compared to the common Amsel test, Nugent scoring or other commercial tests.

Our Take…

Better methods of diagnosing BV are important because they help in creating better treatment methods that will reduce reoccurrence rates and treatment failure.

Read the full study here: https://bmcinfectdis.biomedcentral.com/articles/10.1186/s12879-016-1513-3