Relationship of specific bacteria in the cervical and vaginal microbiotas with cervicitis

Cervicitis is an inflammatory condition of the cervix associated with upper genital tract infection and reproductive complications. Although cervicitis can be caused by several known pathogens, the etiology frequently remains obscure. Here we investigate vaginal bacteria associated with bacterial vaginosis as potential causes of cervicitis. Associations between vaginal bacteria and cervicitis were assessed in a retrospective case control study of women attending a Seattle STD clinic. Individual bacterial species were detected using two molecular methods: quantitative PCR (qPCR) and broad range 16S rRNA gene PCR with pyrosequencing. The primary finding from this initial study was evaluated using qPCR in a validation cohort of Kenyan women. The presence of BVAB3 or Megasphaera species type 2 in the cervix was associated with cervicitis, while the presence of Lactobacillus jensenii was inversely associated. Quantities of these bacteria did not differ between cervicitis cases and controls, but in a model inclusive of presence and abundance, each was significantly associated with cervicitis after adjustment for other cervicitis-causing pathogens. BVAB3 was not associated with cervicitis in our validation study of Kenyan women, possibly due to differences in the clinical definition of cervicitis. Colonization of the endocervix with BVAB3 or Megasphaera species type 2 may contribute to the clinical manifestations of cervicitis, but further study is needed to determine whether this finding is applicable to diverse groups of women. Colonization of the cervix with L. jensenii could be a marker of health, perhaps reducing inflammation or inhibiting pathogenic infection.