Human milk is a very complex fluid that contains numerous bioactive compounds. Among them, it includes very high concentrations of oligosaccharides (human milk oligosaccharides [HMOs]) that group more than a hundred complex sugars. We present an extensive review of the composition and functions of the HMOs, highlighting the influence of the maternal genotype FUT2 on the type and concentration, being the latter much higher in FUT secretory women. The HMOs are non digestible in the intestine of the infant, therefore, they provide a substrate for the development of an intestinal microbiota, mainly rich in bifidobacteria. In addition, since some of these HMOs share some structural sequences with receptors for intestinal pathogens, they act as decoy blocking these receptors preventing their adhesion and proliferation. The benefits of the consumption of these HMOs are considered unique, therefore the synthesis of HMOs structurally identical to those found in breast milk and with similar functionality demonstrated through clinical studies, opens a very interesting line of research in the field of infant nutrition. The first clinical studies conducted with HMOs are analyzed, considering necessary new clinical intervention trials in infants to confirm these effects on the immune system and reducing the frequency of respiratory and gastrointestinal infections.

Correspondencia: C. Martínez-Costa. Hospital Clínico Universitario. Avda. Blasco Ibáñez, 15-17. 46010 Valencia. Correo electrónico: cecilia.martinez@uv.es

Introduction: Infantile colic is a picture of abdominal discomfort, defined by Wessel and included in the Rome III criteria. Although considered benign somewhat related inflammatory markers, causing a disorder in infants and a major anxiety in their family. Lately the use of probiotics such as Lactobacillus reuteri have been successful in other European populations.
Objective: Microbiota modulates intestinal inflammatory response and depends on genetic and environmental factors. We proposed a pilot study to try to reproduce the European results in our population.
Method: Observational prospective study of symptoms associated with colic in 17 healthy infants who were prescribed L. reuteri DSM 17938, indication approved by the Spanish Regulatory Food Agency. In all the written and informed consent of relatives was obteined. Follow-up clinical data using questionnaires and two physical visits to control and determination of calprotectin in feces. Statistical analysis with Stata v11 program chi 2 test and linear regression analysis.
Results: Evolution of clinical parameters such as time crying and infant discomfort were lower as the weeks passed. The perception of improvement and the reduction of faecal calprotectin levels also showed a parallel evolution. The height and weight were not affected.
Conclusions: The use of L. reuteri clearly improves symptoms and reduces infant family anxiety, and the values of intestinal inflammatory markers. Its use does not interfere with the development of weight-height patients. Studies are necessary with larger populations to confirm these initial data.