| dc.description.abstract | It has been suggested that periodontal disease, a disease that affects the supporting
tissues of the teeth, represents a risk factor for adverse pregnancy outcomes. Certain
oral pathogens possess a demonstrated ability to translocate and invade the amniotic
tissues. Once in the amniotic environment, these opportunistic colonisers could then
initiate or contribute to a perinatal infection, and in this way be involved in the
complications. The overall aim of this study was to determine the presence, and
confirm the origin, of suspected maternal oral microbiota in neonatal gastric
aspirates (swallowed amniotic fluid) collected due to complications during
pregnancy and/or evidence of neonatal sepsis.
Non-cultural PCR-based methods directed to the ribosomal encoding genes (rDNA)
were applied to analyse neonatal and maternal samples. The use of universal and
species-specific primers that target the bacterial 16S rRNA gene allowed
identification and quantification of broad-range and specific bacteria to the species
level. Sequence comparative analysis of a more variable fragment, the intergenic
spacer region located between the 16S and the 23S rDNA, was finally used to
compare strains obtained from the neonates and their counterparts in the respective
mother’s oral and vaginal samples.
Data analysis allowed identification of a range of potential confounding factors for
presence of bacteria in the infants, such as vaginal delivery and prolonged rupture of
membranes. However, bacteria with a possible oral origin were mostly identified in
the neonatal samples in low prevalence and not associated with any particular
variable. Quantitative analysis of potential periodontal pathogens demonstrated the
presence of Porphyromonas gingivalis (1%) and Fusobacterium nucleatum (16%) in
the neonates. F. nucleatum was detected at relatively high levels (mean=4.41E+02
cells/ml); representing up to 50% of the total bacterial load, which strongly supports
its possible role in pregnancy complications. Also, F. nucleatum subspecies analysis
and comparisons at the strain level suggest the oral cavity as the most likely origin of
this infectious agent. This study supports the need for further studies. | en_US |
