胃肠外营养相关性胆汁淤积症早产儿肠道菌群特征的研究OA

Objective To analyze the characteristics of the intestinal flora in premature infants with parenteral nutrition-associated cholestasis(PNAC)by high-throughput 16S ribosomal RNA(16S rRNA)sequencing.Methods Using a prospective,longitudinal,single-center cohort study method,the clinical data of 20 premature infants admitted to the Department of Neonatology,Shanxi Provincial Children Hospital from January to August 2022 were collected.Among them,15 premature infants in the PNAC group were sampled for fecal specimens before and after treatment,which were labeled as P1 group(before treatment,age≤28 d,n=15)and P2 group(after treatment,age>29 d,n=15);the non-PNAC group consisted of 5 premature infants who were sampled at the same time points,and their fecal specimens were labeled as C1 group(age≤28 d,n=5)and C2 group(age>29 d,n=5).The clinical data and liver-biliary biochemical indicators were analyzed,and conducted sequencing and bioinformatics analysis on the DNA of the fecal specimens.Statistical methods were performed by t-test,χ2-test and Fisher exact probability method.Results There was no significant difference in general conditions between the PNAC group and the non-PNAC group(all P>0.05),and both groups had good prognosis.The results of linear discriminant analysis effect size(LEfSe)showed the most abundant bacteria in each group:C1 group of Firmicutes and Clostridiaceae,C2 group of Bacillus cereus group,P1 group of Proteobacteria and unclassified Escherichia coli,and P2 group of Bacteroidetes and Corynebacteriaceae.Using Metastats analysis for group-wise t-test,it was found that the abundance of harmful bacteria increased in P1 group compared with C1 group,while the abundance of beneficial bacteria and opportunistic pathogens decreased.The abundance of beneficial bacteria was still low in P2 group compared with C2 group,and the abundance of harmful bacteria was still high.The order of intestinal flora community abundance,uniformity,and diversity in the four samples was P1 group,C2 group,C1 group,and P2 group.The results of the alpha diversity comparison showed that there were statistically significant differences in the abundance-based coverage estimator(ACE)index,Chao1 index,and Shannon index of fecal microbiota abundance between group C1 and group P1(all P<0.05).The results of the beta diversity comparison showed that the principal coordinates analysis(PCoA)indicated that there were significant differences in the microbial community structure among the four groups(R2=0.136,P=0.006).Using PERMANOVA analysis for intergroup difference testing,the results showed that only the C1 group and P1 group had significant differences in microbial community structure(R2=0.146,P=0.004).Conclusion There are significant changes in the intestinal flora of PNAC premature infants before and after treatment.In untreated premature infants with PNAC,the abundance,uniformity and diversity of intestinal flora decreased,the harmful bacteria increased,and the beneficial bacteria decreased.After treatment,the intestinal flora of preterm infants with PNAC gradually returned to normal,and the prognosis was good.Premature infants in the non-PNAC group did not receive probiotics,and there was no change in intestinal flora diversity as their age increased.