Correlation Studies Between Premature Infantswith Feeding Intolerance And Intestinal Flora

Compared to full-term children,because digestive system development is immature, regulate gastrointestinal function is poor, lower gastrointestinal secretion and other factors in preterm children,they were prone to feeding intolerance(FI)in the feeding process.Related studies show that abnormal gut microbes colonization may play a vital role in the incidence of FI in preterm infants.Currently in clinical prokinetic drug trace erythromycin(EM) of treatment for neonatal FI most widely used because of few side effects.In recent years,the literatures were reported that using the EM for a long time could be able to affect the normal intestinal flora colonization.Whether short-term use EM affect intestinal flora colonization of FI children needs further study.Therefore, the study mainly to analysis and compare the diversity and similarity of intestinal bacterial community structure of those who had FI in preterm infants and who are healthy according to microbiology and to analysis the change of the intestinal flora of FI preterm infants before and after using short-term trace EM using SYBR Green Ⅰ real-time fluorescent quantitative PCR. For Clinicians understand the role of gut microbiota changes in the incidence of FI preterm children and to provide the theoretical foundation for the rational use of EM in preterm children with FI. Aims:To analysis and compare the diversity and similarity of intestinal bacterial community structure of those who had FI in preterm infants and who are healthy and to analysis and compare bacterial relative expression levels of Lactobacillus, Escherichia coli, Klebsiella pneumoniae, Enterococcus faecalis of stool samples of FI preterm infants before and after using short-term trace EM. Methods:1. The preterm infants diagnosed as FI during December 2013 to September2014 in neonatal wards of Department of Pediatric, Second Affiliated Hospital of The Fourth Military University were recruited as FI group.The infants without FI who were matched the gestational age,days of age,birth weight with FI group during the same period were taken as the control group.The stool samples were collected in FI group when occurring FI and in control group during the same period, conducting 16 Sr DNA V3 region amplification and DGGE,then to analyze and compare the diversity and similarity of intestinal bacterial community structure between the two groups; 2. The feces of 30 preterm infants with FI and 10 healthy preterm infants were collected. Real-time quantitative PCR were performed to analysis and compare bacterial relative expression levels of Lactobacillus, Escherichia coli, Klebsiella pneumoniae, Enterococcus faecalis of stool samples of two groups; 3. To compare bacterial relative expression levels of four types of bacteria of stool samples of FI group before and after using short-term trace EM. Results:The results of bacterial diversity index showed Shannon-Wiener Index(H) 、Richness(S)、Evenness Index(E)and Simpson’s diversity Index(D)of FI group were lower than the control group;Similarity matrix showed similarity of the flora intra-group was higher than inter-group; 2.Compared with the control group,relative expression levels of Lactobacillus and Enterococcus faecalis of stool samples was lower in the FI group(p<0.01),while relative expression levels of Escherichia coli and Klebsiella pneumoniae was higher in the FI group(p<0.01); 3.The intestinal Escherichia coli and Klebsiella pneumoniae expression level in FI group after treatment with short-term trace EM was lower(p < 0.01),while Lactobacillus and Enterococcus faecalis expression level was higher(p < 0.01). Conclusion:1.The decrease of intestinal microbial community diversity index and community structure disorder may be important factor in preterm infants with FI; 2.Preterm Infants with FI existing structural imbalance of intestinal flora; 3.Using short-term trace EM can improve gastrointestinal function in preterm children with FI without affecting Intestinal microbial colonization in early life.