背景:早产是新生儿死亡的主要原因,极低出生体重的婴儿通常会出现多种并发症。母乳被认为是营养的黄金标准,特别是对于肠道定植延迟的早产儿,因为它含有有益的微生物,如乳杆菌和双歧杆菌。
目的:分析出生体重为1500g或以下的母乳喂养早产儿的肠道菌群。
方法:对妊娠36.6周且出生体重在1500克或以下的早产儿进行了一项观察性研究,出生于蒙特雷大学医院的JoséEleuterioGonzález博士,墨西哥。将40例早产儿分为母乳喂养(BM)和混合喂养(MF)组(BM组21例,MF组19例),从2017年10月到2019年6月。在将其引入任何饲喂类型之前收集粪便样品。在实现完全肠内喂养后,使用16SrRNA基因测序分析了肠道菌群的组成。使用学生t检验或使用Mann-WhitneyU检验对非参数变量进行数值变量比较。支配地位,均匀度,公平性,Margalef\的索引,费希尔的阿尔法,Chao-1指数,并计算了香农多样性指数。
结果:两组之间在属水平上没有观察到显着差异。类别比较表明,与BM组的最终样品相比,初始的α-变形杆菌和β-变形杆菌的计数更高(P<0.011)。此外,最终样本中检测到的γ变形杆菌计数高于初始样本(P=0.040).根据Margalef指数,费希尔的阿尔法,和Chao-1指数,从初始样本到最终样本的物种丰富度下降,无论喂食类型如何,观察到(P<0.050)。四个主要的门是拟杆菌,放线菌,Firmicutes,和变形杆菌,其中变形杆菌是最丰富的。然而,在门水平上,初始样品和最终样品之间没有观察到显着差异。
结论:母乳喂养与α-变形杆菌和β-变形杆菌的减少和γ-变形杆菌的增加有关,为极低出生体重的肠道微生物群结构的文献做出贡献,早产。
BACKGROUND: Preterm birth is the leading cause of mortality in newborns, with very-low-birth-weight infants usually experiencing several complications. Breast milk is considered the gold standard of nutrition, especially for preterm infants with delayed gut colonization, because it contains beneficial microorganisms, such as Lactobacilli and Bifidobacteria.
OBJECTIVE: To analyze the gut microbiota of breastfed preterm infants with a birth weight of 1500 g or less.
METHODS: An observational study was performed on preterm infants with up to 36.6 wk of gestation and a birth weight of 1500 g or less, born at the University Hospital Dr. José Eleuterio González at Monterrey, Mexico. A total of 40 preterm neonates were classified into breast milk feeding (BM) and mixed feeding (MF) groups (21 in the BM group and 19 in the MF group), from October 2017 to June 2019. Fecal samples were collected before they were introduced to any feeding type. After full enteral feeding was achieved, the composition of the gut microbiota was analyzed using 16S rRNA gene sequencing. Numerical variables were compared using Student\'s t-test or using the Mann-Whitney U test for nonparametric variables. Dominance, evenness, equitability, Margalef\'s index, Fisher\'s alpha, Chao-1 index, and Shannon\'s diversity index were also calculated.
RESULTS: No significant differences were observed at the genus level between the groups. Class comparison indicated higher counts of Alphaproteobacteria and Betaproteobacteria in the initial compared to the final sample of the BM group (P < 0.011). In addition, higher counts of Gammaproteobacteria were detected in the final than in the initial sample (P = 0.040). According to the Margalef index, Fisher\'s alpha, and Chao-1 index, a decrease in species richness from the initial to the final sample, regardless of the feeding type, was observed (P < 0.050). The four predominant phyla were Bacteroidetes, Actinobacteria, Firmicutes, and Proteobacteria, with Proteobacteria being the most abundant. However, no significant differences were observed between the initial and final samples at the phylum level.
CONCLUSIONS: Breastfeeding is associated with a decrease in Alphaproteobacteria and Betaproteobacteria and an increase of Gammaproteobacteria, contributing to the literature of the gut microbiota structure of very low-birth-weight, preterm.