Johns Hopkins researchers report that a molecular diagnostic test accurately distinguishes among the three most common causes of vaginitis.
In an article published in Obstetrics & Gynecology, the investigators said that the new assay — based on the presence of the genetic footprints of bacteria, yeast and the sexually transmitted protozoa trichomonas — was as accurate as and more objective than traditional laboratory tests.
‘Overall, the disease prevalence identified by the traditional and the new molecular methods were similar,’ according to Charlotte Gaydos, Professor of Medicine and Director of the Johns Hopkins Centre for the Development of Point of Care Tests for Sexually Transmitted Diseases at the Johns Hopkins University School of Medicine.
The comparative data, she added, earned US Food and Drug Administration market authorisation for use by diagnostic laboratories. The assay is licensed to BD Diagnostics, which will market it under the BD MAX™ Vaginal Panel.
‘Diagnostic tests traditionally used to distinguish among the causes of vaginitis are archaic, quite subjective and time-intensive, plus they require extensive training for those reading the results,’ Gaydos noted.
Labs must grow cultures, conduct microscopic studies of cells for infection and even smell samples in what is commonly known as the ‘whiff’ test to help differentiate among possible causes and select the proper treatment.
‘The new test is objective. Either the DNA of the causative agent is there or not; no grey area,’ said Gaydos.
The new molecular test first uses a real-time polymerase chain reaction (PCR) to amplify large amounts of specific DNA sequences from the three most common causes of vaginitis from patient samples, then reads either a positive or a negative result based on whether enough DNA is present to indicate infection.