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Objective: Microbial biofilms are communities of sessile microorganisms formed by cells that are attached irreversibly to a substratum or interface or to each other and embedded in a hydrated matrix of extracellular polymeric substances. Microbial biofilms have been implicated in >80% of human infections such as periodontitis, urethritis, endocarditis, and device-associated infections. Thus far, intraamniotic infection has been attributed to planktonic (free-floating) bacteria. A case is presented in which "amniotic fluid sludge" was found to contain microbial biofilms. This represents the first report of a microbial biofilm in the amniotic cavity., Study Design: "Amniotic fluid sludge" was detected by transvaginal sonography and retrieved by transvaginal amniotomy. Bacteria were identified with scanning electron microscopy and fluorescence in situ hybridization for conserved regions of the microbial genome; the exopolymeric matrix was identified by histochemistry by the wheat germ agglutinin lectin method. The structure of the biofilm was imaged with confocal laser scanning microscopy., Results: "Amniotic fluid sludge" was imaged with scanning electron microscopy, which allowed the identification of bacteria embedded in an amorphous material and inflammatory cells. Bacteria were demonstrated with fluorescent in situ hybridization using a eubacteria probe. Extracellular matrix was identified with the wheat germ agglutinin lectin stain. Confocal microscopy allowed 3-dimensional visualization of the microbial biofilm., Conclusion: Microbial biofilms have been identified in a case of intraamniotic infection with "amniotic fluid sludge."

Objective: To evaluate the association between various microorganisms isolated from the genital tract in pregnant women with bacterial vaginosis., Study Design: A cross-sectional population-based study among pregnant women addressed at their first antenatal visit before 24 full gestational weeks from the referring area of the Department of Obstetrics and Gynecology at Odense University Hospital, Denmark, from November 1992 to February 1994. The main outcome measures were prevalence of various microorganisms and statistical estimates of interactions (crude, adjusted, and relative odds ratios) between the microorganisms isolated from the lower genital tract in pregnant women with and without clinical diagnosis of bacterial vaginosis., Results: Three thousand five hundred ninety-six (3596) pregnant women were asked to participate. Of the 3596 pregnant women 3174 (88.4%) agreed to participate before 24 full gestational weeks. After controlling for the presence of other microorganisms, strong associations between Gardnerella vaginalis, anaerobic bacteria, Mycoplasma hominis, and present bacterial vaginosis were found. Similarly Lactobacillus spp. were found to be associated with the absence of bacterial vaginosis. The combination of G. vaginalis and anaerobic bacteria and/or M. hominis was found in 59.6% of the cases with bacterial vaginosis and in 3.9% of the cases without bacterial vaginosis (odds ratio 36.4, 95% confidence interval 27.8 to 47.8). The crude odds ratio was found to be as high as 74.8 (95% confidence interval 32.3 to 174.1) when the combination of G. vaginalis, M. hominis, anaerobic bacteria, and no Lactobacillus spp. was associated with bacterial vaginosis., Conclusion: There is a microbial foundation for bacterial vaginosis, and it is possibly due to an intermicrobial interaction in which the microorganisms G. vaginalis, anaerobic bacteria, and M. hominis are dominating, indicating that these constitute the pathologic core of bacterial vaginosis.

Objective: Our goal was to evaluate the effect of Escherichia coli, Bacteroides fragilis, Mycoplasma hominis, and Staphylococcus aureus on cytokine and prostaglandin production by amnion cells in vitro., Study Design: Amnion cells were obtained from women undergoing elective cesarean section before the onset of labor and cultured in a primary cell culture. Confluent amnion cells were incubated with heat-inactivated bacteria in different concentrations (10(1) to 10(6) colony-forming units/ml) for 48 hours. Samples for quantification of interleukin-1 beta, interleukin-6, interleukin-8, tumor necrosis factor-alpha, and prostaglandin E2 were collected at 6, 12, 24, and 48 hours., Results: Under basal conditions, minor amounts of interleukin-6 and interleukin-8 were detectable. Incubation of amnion cells with E. coli enhanced the secretion of interleukin-8 and also induced an transient increase of prostaglandin E2 in a dose-dependent manner. B. fragilis produced an increase in the secretion of interleukin-6 and interleukin-8. M. hominis and S. aureus did not cause an increase in either interleukin-6, interleukin-8, or prostaglandin E2., Conclusion: The gram-negative bacteria E. coli and B. fragilis stimulated interleukin-6 and interleukin-8 to a greater degree than the other bacteria investigated in this study. This finding may be of clinical interest in the onset of preterm birth.