We carried out shotgun metagenomics on longitudinal faecal samples isolated from ELBW infants. We performed various bioinformatics analysis to characterise the taxonomic diversity (species and strain level), and frequency of antibiotic resistance genes. Genomic findings were validated with phenotypic testing (i.e. Minimal Inhibitory Concentration.. Characterisation of the preterm infant reservoir of antibiotic resistance genes

Preterm infants, particularly extremely low birth weight infants often receive early empiric antibiotic treatment from birth.The duration of the course is very subjective and is based on the clinician’s opinion on antepartum factors and prematurity of the baby. Notably, administration of antibiotics disrupts the resident gut microbiota, and may create an important reservoir of resistant strains, and of transferable resistance genes, the so called ’resistome’, which may correlate with the increasing incidence of antimicrobial resistance (AMR). Thus, in this study we sought to determine the impact of specific antibiotic regimens on the preterm microbiota, and the ‘resistome´.