CHARLESTON, S.C. — Sexually transmitted diseases and bacterial vaginosis are known to be associated with elevated cervical proinflammatory cytokines in pregnancy, and interim results from an ongoing study suggest that vaginal flora that are opportunistic pathogens also have such an effect.
Candida albicans, Escherichia coli, and group B streptococci all were associated with elevations in specific cytokines in the 244 women enrolled in the study who were available for interim analysis, Marijane A. Krohn, Ph.D., reported at the annual meeting of the Infectious Diseases Society for Obstetrics and Gynecology.
“C. albicans, E. coli, and group B streptococci are very frequent colonizers in asymptomatic women—however, these microorganisms appear ready to start an inflammatory process, even when by local vaginal criteria they seem to be nonpathogenic at that time or quiescent,” Dr. Krohn said.
Given that these organisms are pathogenic to immunologically naive fetuses and neonates, and that they also can cause infection in women, it makes sense that they would show some pathogenic potential by being associated with elevated proinflammatory cytokines, she noted.
The women were sampled before 16 weeks' gestation, and some of them also were sampled later in pregnancy.
Cervical proinflammatory cytokines were considered elevated if they were at or above the 75th percentile on any sample, said Dr. Krohn of the University of Pittsburgh.
Of 80 patients who had C. albicans, 47% of them had elevated levels of interleukin (IL)-1α, and 51% of them had elevated levels of IL-1β.
The number of patients with IL-1α and IL-1β at these levels was significantly higher in the participants with C. albicans colonization, compared with those participants without C. albicans colonization. IL-6 was also significantly higher in the colonized group.
Similarly, of the 28 patients with E. coli, 54% had IL-1α at or above the 75th percentile, and significantly more of those with E. coli colonization had elevated IL-1α and IL-1βcompared with those without such colonization.
The researchers said only IL-6 was significantly elevated in the participants who had group B streptococci colonization, compared with the participants of the study without group B streptococci.