Bacterial Diversity of the Gastric Content of Preterm Infants during Their First Month of Life at the Hospital

Abstract

Studies focused on the stomach microbiota are relatively scarce, and most of them are focused on the adult population. The aim of this work is to describe the bacterial communities inhabiting the gastric content (GC) of preterm neonates. For that purpose, GC samples were collected weekly from a total of 13 preterm neonates during their first month of life within their hospital stay. Samples were analyzed by using both culture-dependent and -independent techniques. The former allowed the isolation of bacteria belonging mainly to the genera Enterococcus, Staphylococcus, Streptococcus, Serratia, Klebsiella, and Escherichia. The cultured dominant species in the GC samples during all the hospitalization period were Enterococcus faecalis and Staphylococcus epidermidis. Multilocus sequence typing (MLST) analysis revealed the presence of high-risk clonal complexes associated with the hospital environment, which may colonize enteral feeding tubes. Similarly, the 16S rRNA sequencing showed that Streptococcus, Staphylococcus, Lactobacillus, Enterococcus, Corynebacterium, and Propionibacterium were the dominant genera present at 75% of the gastric samples. However, the genera Serratia, Klebsiella, and Streptococcus were the most abundant. Own mother’s milk (OMM) and donor milk (DM) were collected after their pass through the external feeding tubes to assess their bacterial content. OMM and DM had a similar bacterial pattern to GC. Based on these data, the GC of preterm neonates is dominated by Proteobacteria and Firmicutes and harbors high-risk bacterial clones, which may colonize enteral feeding tubes, and therefore the feeds that pass through them.

Clinical characteristics influence cultivable-bacteria composition in the meconium of Indonesian neonates

“…Moreover, the mode of breastfeeding (direct breastfeeding and indirect breastfeeding) could be assumed as a cause of more diverse meconium microbiota in exclusive breastfeeding (EBF) neonates. Enterobacteriaceae and potential pathogens were shown to be enriched with indirect breastfeeding, consistent with culture-dependent studies where pump expression increased the abundance of Enterobacteriaceae and other Gram-negative bacteria in milk [ 25 , 26 ]. However, another study has found no significant differences in gut microbial communities between EBF and non-EBF infants [ 27 ].…”

The Effects of Helicobacter pylori Infection on Gastric Microbiota in Children With Duodenal Ulcer

“…Serratia is one of the major bacteria in the stomach of H. pylori -negative individuals ( Li et al, 2017 ). Serratia is reported to be the most abundant genera in the gastric microbiota of both preterm infants and formula milk-fed infants with a median relative abundance of 15.68% and 34.20%, respectively ( Moles et al, 2017 ; Ku et al, 2020 ). Serratia is often found in the living environment (children’s toys) and pathological conditions (blood infections, skin abscesses, bacterial meningitis, et al) ( Martín-Nalda et al, 2011 ; Abdinia et al, 2014 ; Martínez-Bastidas et al, 2014 ; Johnson et al, 2020 ).…”

Staphylococcus epidermidis in feedings and feces of preterm neonates

“…The different milk types were subsequently administered through enteral feeding tubes which are well-suited devices for the growth and enrichment of high risk hospital-associated clones, which subsequently act as reservoirs of such clones [28,[50][51][52]. In preterm neonates, gastric pH values are closer to neutrality while the pylorus is more relaxed than in adults; this allows the entry of gut bacteria to the gastric compartment.…”