The effect of a fructo-oligosaccharide supplemented formula on gut flora of preterm infants.

AIM: The intestinal flora of breast-fed infants is generally dominated by bifidobacteria which have beneficial properties. Their presence is due to various components of breast milk, including prebiotic substances. This prospective double-blind study compared the numbers of bifidobacteria in the stool flora of bottle-fed preterm infants randomized to receive for 14 days either a formula with prebiotic fructo-oligosaccharides at a concentration of 0.4 g/dL or the same formula with maltodextrin as a placebo. METHODS: Within 0-14 days after birth, 56 healthy bottle-fed infants were enrolled to receive either the prebiotic or placebo. Faecal samples were taken at inclusion day and at study day 7. The number of bifidobacteria in the stools, stool characteristics and somatic growth were recorded during the study. RESULTS: In the group fed fructo-oligosaccharides, both the numbers of bifidobacteria in the stools and the proportion of infants colonized with them were significantly higher as compared to the placebo group (p=0.032 and p=0.030 respectively). There was also a higher number of bacteroids in the fructo-oligosaccharide group as compared to the placebo (p=0.029). At the same time, reduction was noted in the numbers of Escherichia coli and enterococci. (p=0.029, and p=0.025, respectively). Supplementation had also significant influence on stool frequency per day (p=0.0080). CONCLUSION: An infant formula containing a small quantity of prebiotic oligosaccharides is well accepted and leads to rapid growth of bifidobacteria in the gut of bottle-fed preterm infants while decreasing the numbers of pathogenic microorganisms.

The effect of neonatal jaundice on biotinidase activity.

BACKGROUND: Jaundice is one of the most common and one of the vexing problems that can occur in newborns. A newborn screening test for biotinidase deficiency has been added to many national screening programmes. AIM: To clarify the problem of false-positive screening tests in neonates, especially in term babies, we evaluated the biotinidase activity in the serum of fullterm, premature and small-for-dates newborn infants with jaundice. METHODS: 1296 fullterms (controls N=426), 246 prematures (controls N=86) and 156 small-for-dates babies (controls N=38) aged 2-3 days with jaundice were included in the study. In jaundiced neonates and controls, 3.0 ml of blood was drawn for the evaluation of total bilirubin (t.bil), liver enzymes and biotinidase activity in the serum using a fluorimetric method. In order to test whether or not t.bil causes an artifact in the previous method, biotinidase activity was also evaluated in a number of jaundiced newborns using an HPLC method. Additionally, a preliminary in vitro experiment was carried out to test whether t.bil is an inhibitor of the enzyme. RESULTS: Biotinidase activities in the group of controls of prematures (3.30+/-1.2 mmol/min/l) and small-for-dates babies (3.34+/-0.8 mmol/min/l) were lower than those of term babies (4.99+/-1.1 mmol/min/l, p<0.001). T.bil and liver enzymes showed a statistically significant inverse correlation with biotinidase activity (p<0.001) in all the jaundiced infants of this study. Additionally, biotinidase activity, evaluated in a number of neonates with both fluorimetric and HPLC methods showed similar results. Preincubation of the serum enzyme with t.bil (>10 mg/dl) resulted in a 50% or more inhibition. CONCLUSIONS: (a) Low biotinidase activity was found in term babies, prematures and small-for-dates with jaundice. (b) The low activity of the enzyme could be due to their impaired liver function. (c) The high t.bil levels in the studied groups may play the role of an "inhibitor" of the enzyme. (d) Gestational age as well as t.bil levels should always be written on Guthrie cards for a correct evaluation of biotinidase activity.