Antagonistic effect of Lactobacillus strains against gas-producing coliforms isolated from colicky infants

<p>Abstract</p> <p>Background</p> <p>Infantile colic is a common disturb within the first 3 months of life, nevertheless the pathogenesis is incompletely understood and treatment remains an open issue. Intestinal gas production is thought to be one of the causes of abdominal discomfort in infants suffering from colic. However, data about the role of the amount of gas produced by infants' colonic microbiota and the correlation with the onset of colic symptoms are scanty. The benefit of supplementation with lactobacilli been recently reported but the mechanisms by which they exert their effects have not yet been fully defined. This study was performed to evaluate the interaction between <it>Lactobacillus </it>spp. strains and gas-forming coliforms isolated from stools of colicky infants.</p> <p>Results</p> <p>Strains of coliforms were isolated from stools of 45 colicky and 42 control breastfed infants in McConkey Agar and identified using PCR with species-specific primers, and the BBL™ Enterotube™ II system for <it>Enterobacteriaceae</it>. Gas-forming capability of coliforms was assessed in liquid cultures containing lactose as sole carbon source. The average count of total coliforms in colicky infants was significantly higher than controls: 5.98 (2.00-8.76) log₁₀<it>vs </it>3.90 (2.50-7.10) CFU/g of faeces (p = 0.015). The following strains were identified: <it>Escherichia coli</it>, <it>Klebsiella pneumoniae</it>, <it>Klebsiella oxytoca</it>, <it>Enterobacter aerogenes</it>, <it>Enterobacter cloacae </it>and <it>Enterococcus faecalis</it>. Then, 27 <it>Lactobacillus </it>strains were tested for their antagonistic effect against coliforms both by halo-forming method and in liquid co-cultures. <it>Lactobacillus delbrueckii </it>subsp.<it>delbrueckii </it>DSM 20074 and <it>L. plantarum </it>MB 456 were able to inhibit all coliforms strains (halo-forming method), also in liquid co-cultures, thus demonstrating an antagonistic activity.</p> <p>Conclusions</p> <p>This study shows that two out of 27 strains of <it>Lactobacillus </it>examined possess an antimicrobial effect against six species of gas-forming coliforms isolated from colicky infants. Our findings may stimulate new researches to identify which <it>Lactobacillus </it>strains can improve colicky symptoms by acting on coliforms gut colonization.</p

Quantitative ultrasound applied to metacarpal bone in infants.

Aim. To provide bone status assessment in infancy using quantitative ultrasound (QUS) applied to second metacarpus.Methods. 103 healthy term infants and 3 patients with rickets, aged ≤ 12 months, underwent metacarpal QUS evaluation using QUS DBM Sonic Aurora IGEA (MO, Italy), which measures speed of sound (mcSOS) and bone transmission time (mcBTT).Results. In the total sample, median (interquartile range) of mcSOS was 1640.00 (26.0) m/s and mcBTT 0.82 (0.21) µs. Moreover, reference values for age were obtained based on estimation of the lower and upper percentiles. We observed a statistical significant difference between groups of age for mcSOS (p = 0.016). In a multiple linear regression model, we found a relation between age at enrolment and mcSOS (β = −0.608; p = 0.000) and mcBTT (β = −0.819; p = 0.001). A positive correlation between mcSOS and mcBTT has been observed (r = 0.631; p = 0.000). All the patients with rickets showed values of mcSOS and mcBTT lower than the 10th percentile.Conclusion. Our findings show that this new simple technique appears to be a promising tool for monitoring bone mineral status in pediatric clinical practice and in early life. Furthermore, it could be considered a useful method to investigate and to monitor the role of different factors on programming of bone health and it should be tested as a new method for monitoring subjects with rickets during therapy