Introduction: Parameters allowing regular evaluation of renal function in a paediatric intensive care unit (PICU) are not optimal. The aim of the present study was to analyse the utility of serum cystatin C and beta2-microglobulin (B2M) in detecting decreased glomerular filtration rate in critically ill children. Methods: This was a prospective, observational study set in an eight-bed PICU. Twenty-five children were included. The inverses of serum creatinine, cystatin C, and B2M were correlated with creatinine clearance (CrC) using a 24-hour urine sample and CrC estimation by Schwartz formula (Schwartz). The diagnostic value of serum creatinine, cystatin C, and B2M to identify a glomerular filtration rate under 80 ml/minute per 1.73 m² was evaluated using receiver operating characteristic (ROC) curve analysis. Results: Mean age was 2.9 years (range, 0.1 to 13.9 years). CrC was less than 80 ml/minute per 1.73 m² in 14 children, and Schwartz was less than 80 ml/minute per 1.73 m² in 9 children. Correlations between inverse of B2M and CrC (r = 0.477) and between inverse of B2M and Schwartz (r = 0.697) were better than correlations between inverse of cystatin C and CrC (r = 0.390) or Schwartz (r = 0.586) and better than correlations between inverse of creatinine and CrC (r = 0.104) or Schwartz (r = 0.442). The ability of serum cystatin C and B2M to identify a CrC rate and a Schwartz CrC rate under 80 ml/minute per 1.73 m² was better than that of creatinine (areas under the ROC curve: 0.851 and 0.792 for cystatin C, 0.802 and 0.799 for B2M, and 0.633 and 0.625 for creatinine). Conclusion: Serum cystatin C and B2M were confirmed as easy and useful markers, better than serum creatinine, to detect acute kidney injury in critically ill children.

Extensive work has established the importance of the gut microbiota during the first years of life. However, there are few longitudinal studies describing the role of infants' diet on the evolution of the fecal microbiota and their metabolic activity during this stage. The aim of this work was to explore the impact of diet on the composition of the major intestinal microorganisms and their main microbial metabolites from birth to 12 months. This is a longitudinal prospective study of diet and fecal microbiota. Bacterial groups levels were determined by qPCR and short-chain fatty acids (SCFAs) concentrations by gas chromatography. Information from self-administered questionnaires about general characteristics and food frequency were obtained from a cohort of 83, Spanish and full-term, infants at 15, 90, 180 and 365 days of age. Results revealed that Enterobacteriaceae decrease in weaning period contrary to Bacteroides group and Clostridium cluster IV. CONCLUSION: our study supports weaning period as a key step for gut microbiota transition and suggests the importance of the consumption of dietary fiber with the increase of certain bacterial groups as Clostridium cluster IV, which could be beneficial for the host. Finally, studies specially designed to analyze the production and the excretion of SCFAs in children are needed to understand how diet could influence in this process.

The first years of life represent a window of opportunity to establish proper dietary patterns and to maintain them over time. Our aim was to describe the diet of a cohort of Spanish children, from 2 to 36 months, and to identify the components that could influence the quality of the diet at 24 and 36 months of age. This was a longitudinal prospective study analyzing information from administered questionnaires about general characteristics and food frequency consumption in 97 full-term babies. At 2–3 months of age, only 53.6% of infants were observed to be breastfed. The intake of animal foodstuffs from 12 to 36 months was higher than national recommendations, and the contrary was true for fruits and vegetables. The intake of vitamin D was below European Food Safety Authority recommendations. Moreover, energy intake at 6 months was inversely associated with Mediterranean Diet Score (MDS) at 24 months, whereas vegetables intake was positively associated with MDS at 36 months. These results could be useful in the creation of future guidelines focused on the promotion of breastfeeding and healthy early-life food habits.

Ensuring the nutritional demands of preterm (PT) infants during complementary feeding could contribute significantly to the infants’ long-term health and development. However, the dietary guidelines for complementary feeding in PT are scarce. Thus, describing dietary intake and identifying nutritional targets for these infants could be of great interest. The aim of this study is to assess the food intake and anthropometric parameters in a Mediterranean infant cohort from 6 to 24 months and to identify nutritional targets especially focused on late preterm infants. This is a longitudinal prospective study analyzing information from administered questionnaires about general characteristics and food frequency consumption in 115 infants (20 PT (32 to 36 gestational weeks), 95 full-term (FT)) at 6, 12 and 24 months of age. Results show that the differences in the prevalence of underweight observed in PT infants vs. FT infants are maintained for up to 6 months of age but disappear at 12 and 24 months. The age of inclusion of new foods and the average intake of the main food groups was not different from that of FTs. Although protein intake at 6 months was directly correlated with weight gain and growth in FT, these associations were not observed in PT. At the nutritional level, the low intake of vitamin D in preterm infants is noteworthy. These findings may be useful when designing new intervention strategies for this population group.

Knee pain is one of the most frequent musculoskeletal symptoms in young physically active males. Common entities of clinical diagnosis as osteochondritis/apophysitis and others that need complementary studies should be considered in the differential diagnosis. We present the case of a 12-year-old male athlete with continuous pain in his right knee that intensifies with physical activity and with direct pressure. Diagnosis of Osgood-Schlatter disease is made by exploratory data, pain-to-finger palpation on the anterior tibial tuberosity, and is confirmed by radiology. This entity is described as well as the main pathologies derived from overuse to make differential diagnosis and to stress preventive measures regarding a correct orientation in the sport activity.