The researchers collected stool, saliva, and skin swabs from six low birth weight infants (five of whom were born premature) that ranged in weight from 1.65 - 4.01 lbs on postnatal days 8, 10, 12, 15, 18, and 21. They amplified, pyrosequenced, and analyzed the bacterial 16S genes present in each sample and compared them with analogous data from normal-birthweight (NBW) infants and healthy adults.
In the 8 - 21 day age range, there was a subtle but important divergence in the composition of the oral and gut microbiotas, a differentiation that was mostly driven by changes that evolved in the composition of the gut microbiome. The babies' microbiomes were also dominated at times by bacterial types that have been associated with newborn infections and necrotizing enterocolitis, including Staphylococcus, C. perfringens, P. aeruginosa and others.
The scientists also tracked the effects of antibiotic treatment in one infant in the study, noting the rise of a type of Mycoplasma in the mouth that has previously been associated with vaginal infection.
Of the three sites studied, neonatal skin was the most adult-like in its microbiota composition. And like healthy adults, the microbiota of the different body sites in the infants was apparently determined mostly by body site and by host individual.
Co-author Michael J. Morowitz of the University of Pittsburgh School of Medicine says understanding the vulnerability of preemies from a microbial perspective can provide insights into how to better care for them.
"Premature infants are unique because they can spend several months in the hospital, where they're exposed to virulent bacteria, they also frequently have antibiotics exposure, and they're dietary intake is irregular - sometimes they're not able to eat anything by mouth. That probably effects colonization patterns," says Morowitz. "The first step [in understanding this] is
|Contact: Jim Sliwa|
American Society for Microbiology