Despite being one of the most common infections among women, scientists and doctors know little about the causes of bacterial vaginosis (BV), a usually benign disease that is also linked to serious health problems including pelvic inflammatory disease, an increase in the viral load of HIV from infected women and a two-fold increase in risk for pre-term labor and delivery.
Now researchers at the Fred Hutchinson Cancer Research Center have shed new light on BV by using genetic-sequencing technology to detect several new bacterial species - enough to almost double the number of known strains associated with the infection.
The findings - as well as a related editorial - will be published in the Nov. 3 edition of the New England Journal of Medicine.
These newly described uncultivated bacterial strains could be a reason for BV's high relapse rate - up to 30 percent - and could lead to the development of new diagnostic tests and better treatment approaches that target some of these novel bacteria. The knowledge also eventually will help doctors determine if particular uncultivated bacterial species are responsible for the serious complications associated with BV, according to David Fredricks, M.D., assistant member of the Infectious Diseases Program at the Hutchinson Center's Clinical Research Division.
BV is usually harmless and easily treated with antibiotics. Symptoms include malodorous discharge, itching and burning, however, some women with BV have no symptoms. Despite its prevalence (10 percent to 20 percent in Caucasian women and 30 percent to 50 percent in African-American women in the United States) the cause of BV is not well understood by scientists and doctors, Fredricks said.
"With most bacterial infections, you identify what the bacterium is and you treat that bacterium," said Fredricks, who is also an assistant professor in the Division of Allergy and Infectious Disease at the University of Washington School of Medicine. "The problem with BV is we don't know what we're treating. We know some of the strains associated with BV, however many strains that are cultured in the lab are not sensitive to the usual antibiotic treatments, yet patients may respond to therapy. We need to find out which bacteria cause BV and why some women either respond to antibiotic treatment or fail to be cured."