Development of a species-specific polymerase chain reaction assay for Gardnerella vaginalis

The nucleotide sequence of the region between the 16S and 23S rRNA genes of the facultative anaerobic bacterium Gardnerella vaginalis has been determined, together with the 5' proximal 500 nucleotides of the 23S rRNA gene. Regions suited for the development of specific, probe-confirmable polymerase chain reaction (PCR) assays were selected. PCR assays were evaluated with respect to sensitivity and specificity, the latter in comparison with a number of G. vaginalis reference strains and closely related species like Bifidobacterium spp. In an initial diagnostic study it appeared that the PCR test detected G. vaginalis in 40% of women irrespective of their clinical status. Ten out of 11 patients suffering from bacterial vaginosis as defined on the basis of clinical parameters were carrying G. vaginalis.