The effect of enteral supplementation of specific neutral and acidic oligosaccharides on the faecal microbiota and intestinal microenvironment in preterm infants

We aimed to determine the effects of enteral supplementation of a prebiotic mixture of neutral and acidic oligosaccharides (scGOS/lcFOS/pAOS) on the faecal microbiota and microenvironment in preterm infants. Furthermore, we determined the influence of perinatal factors on the development of the faecal microbiota. In a randomised controlled trial, preterm infants with gestational age <32 weeks and/or birth weight <1,500 g received enteral supplementation of scGOS/lcFOS/pAOS or placebo (maltodextrin) between days 3 and 30 of life. Faecal microbiota, as measured with fluorescent in situ hybridisation (FISH), and microenvironment [short-chain fatty acids (SCFAs), pH, sIgA] were measured at four time points: before the start of the study and at days 7, 14 and 30 of life. In total, 113 preterm infants were included. Enteral supplementation of the prebiotic mixture increased the total bacteria count at day 14 (Exp 3.92; 95 % confidence interval [CI] 1.18–13.04, p = 0.03), but not at day 30 (Exp 1.73; 95 % CI 0.60–5.03, p = 0.31). There was a trend toward increased bifidobacteria counts. There was a delayed intestinal colonisation of all bacteria. Enteral supplementation of the prebiotic mixture decreased the faecal pH (Exp 0.71; 95 % CI 0.54–0.93, p = 0.01) and there was a trend toward increased acetic acid compared to the placebo group (Exp 1.09; 95 % CI 0.99–1.20, p = 0.10). There was no effect on sIgA (Exp 1.94; 95 % CI 0.28–13.27, p = 0.50). Antibiotics decreased the total bacteria count (Exp 0.13; 95 % CI 0.08–0.22, p < 0.001). Enteral supplementation of a prebiotic mixture of neutral and acidic oligosaccharides increases the postnatal intestinal colonisation. However, the extensive use of broad-spectrum antibiotics in preterm infants decreased the growth of all intestinal microbiota, thereby, delaying the normal microbiota development.