Preterm infants (born before 37 weeks gestation) are highly susceptible to disease,
with necrotising enterocolitis (NEC) and late-onset sepsis (LOS) having the greatest
impact on mortality and morbidity. This study investigated gut microbiome
interactions, examining the influence of bacterial abundance, probiotics,
metagenomic pathways and the short chain fatty acid (SCFA) butyric acid under
16S rRNA MiSeq Illumina Next Generation Sequencing (NGS) was applied to
preterm infant stool samples in Chapter 3: (N=2, n=16) with probiotics and LOS; and
Chapter 4: (N=34, n=172) of which NEC (N=13, n=66), No NEC (N=21, n=106), LOS
(N=5, n=24), No LOS (N=29, n=148), with probiotics (N=19, n=79) without probiotics
(N=15, n=93). Chapter 5: SCFAs in mothers breast milk samples (N=16, n=59),
were analysed (UPLC-QTOF MS); without NEC (N=10, n=43,) with NEC (N=6,
n=16), with LOS (N=2, n=13) and without LOS (N=14, n=46).
Chapter 3: Bifidobacterium abundance increased before sepsis. Infant 1 had
reduced Staphylococcus (p-value < 0.001) and increased Lactococcus (p-value <
0.01). Chapter 4: samples without NEC had greater α-diversity (p-value < 0.001).
Bifidobacterium was reduced at NEC onset (p-value = 0.003). Probiotics increased
α-diversity (p-value < 0.001), Bifidobacterium, Yersinia, Lactococcus, Lactobacillus
(all p-value < 0.001), Escherichia / Shigella (p-value = 0.021), Enterococcus (p-value
= 0.004) with reduced Staphylococcus (p-value < 0.001). Probiotics were linked to
metabolic pathways for energy acquisition and immunoregulatory response.
Chapter 5: preterm infants that developed NEC had increased butyric acid in breast
milk (p-value = 0.001).
|Date of Award||15 Oct 2022|
|Supervisor||Caroline Orr (Supervisor), Gillian Taylor (Supervisor), Andrew Nelson (Supervisor) & Gregory Young (Supervisor)|