Introduction: Neonatal sepsis and necrotizing enterocolitis are associated with gut dysbiosis in preterm infants. Probiotics contributes to prevention of both illnesses; however, the impact on ecological features of early-life microbial succession is not well studied beyond the bacterial component. Our objective was to study the longitudinal effects of probiotics supplementation on intestinal colonization with bacterial and fungal microbiome in extremely low birth weight (ELBW) infants.
Methods: A randomized, open-label, controlled trial in ELBW-infants. The intervention arm received Florababy®, a combination of 4 Bifidobacterium species (breve, bifidum, longum, and infantis) together with Lactobacillus rhamnosus. The control group received routine care. Stool samples were collected at first week of life, 2 and 4 weeks after probiotic initiation and 2 weeks after cessation, and at equivalent time-points in the control group. Stool samples were analyzed using strains specific qPCR, and 16sRNA and ITS2 genes sequencing of bacterial and fungal composition. A pre-protocol approach was used for the microbial analysis
Results: Of the 62 ELBW infants enrolled in the trial, in the intervention arm only 26 received probiotics and 4 did not. Compared to the control, higher concentrations of probiotics strains were detected in the probiotics group, even after treatment cessation (P<0.001). Sequencing data showed increase bacterial richness and alpha diversity even after treatment cessation. Beta diversity increased with probiotics use during treatment period for fungal microbiome and continued beyond treatment cessation for bacterial microbiome (p=0.001). Dirichlet multinomial mixtures analysis identified two bacterial clusters; Cluster 1 represent strains abundance during early weeks of life, and cluster 2 strains were similar to later gestational weeks. Probiotics use enhanced richness and Beta diversity in Cluster1 (p=0.001)
Conclusion: Probiotics supplementation results in significant changes in bacterial and fungal microbiome composition which continue after probiotics cessation for bacterial composition. Analyses of stool samples at 6 and 12 months of age are underway.
Belal Alshaikh– Clinical Assistant Professor, Department of Pediatrics Cumming School of Medicine University of Calgary
Marrie Claire Arrieta– Assistant Professor, Department of Physiology and Pharmacology, University of Calgary, Calgary, Alberta, Canada. 2 Department of Pediatrics, University of Calgary, Calgary, Alberta, Canada. 3 International Microbiome Centre, Cumming School of Medicine, Health Sciences Centre
Amuchou Soraisham– Associate professor, Department of Pediatrics Cumming School of Medicine University of Calgary
Harish Amin– professor,, Department of Pediatrics Cumming School of Medicine University of Calgary