Evaluation du bénéfice et de la tolérance du traitement par hormone de croissance dans le syndrome de Prader-Willi

FORT-DE-FRANCE-CHRU-BU (972332102) / SudocBORDEAUX2-BU Santé (330632101) / SudocSudocFranceF

Isolation and Characterization of Commensal Bifidobacteria Strains in Gut Microbiota of Neonates Born Preterm: A Prospective Longitudinal Study

Bifidobacterial population dynamics were investigated using a longitudinal analysis of dominant species isolated from feces of neonates born preterm (singletons (n = 10), pairs of twins (n = 11)) from birth up to 16 months of age. We performed quantification, isolation, and identification of the dominant bifidobacteria strains. The genetic relationship of the isolates was investigated via pulsed field gel electrophoresis (PFGE) genotyping, and PCR was used to screen the specific genetic marker tet genes. Additionally, all of the isolated strains were phenotypically characterized by their response to gastro-intestinal stresses and the MIC determination of tetracycline. In the same individual, our results showed a turnover of the bifidobacteria dominant population not only at species but also at strain levels. In addition, we found clonally related strains between twins. A minority of strains were tolerant to gastric (6%) and intestinal (16%) stresses. Thirteen percent of the strains were resistant to tetracycline. This work is original as it provides insights at the strain level of the early life in vivo dynamics of gut microbiota bifidobacteria in preterm neonates. It highlights the need to take into consideration the fluctuation of bifidobacteria populations that may occur for one individual

Faecal calprotectin and gut microbiota do not predict enteropathy in very preterm infants

International audienceAim: Very preterm birth is associated with a high risk of enteropathies. Diagnosis is challenging, especially in mild forms, leading to unnecessary periods of cessation of enteral feeding. This study aimed at establishing a prognosis score of enteropathy combining clinical parameters and faecal calprotectin concentration.Methods: This prospective multicentric study included preterm neonates born at a gestational age of 33 weeks or less. Stools were collected weekly until hospital discharge, and daily in case of digestive events for calprotectin measurement (ELISA and immunochromatography) and microbiota analyses (16S rRNA gene sequencing).Results: Among the 121 neonates included, 21 experienced at least one episode of enteropathy, mainly mild forms. By ELISA testing, median faecal calprotectin was 88 (8-798) µg/g faeces. No statistically significant association was found between the outset of enteropathy and maternal and neonatal characteristics, and calprotectin levels. The agreement between ELISA and immunochromatography assay was moderate (intra-class correlation coefficient 0.58, 95%CI [0.47-0.66]). Comparison of species diversity and relative bacterial abundance profiles between infants with or without enteropathy revealed no specific alterations associated with enteropathy.Conclusion: The study failed to propose a prognostic score of enteropathy, probably due the large inter- and intra-individual variability of faecal calprotectin in very preterm neonates