The Intestinal Dysbacteriosis in the Pathogenesis of Necrotizing Enterocolitis

Study DescriptionThe goal of this observational study is to detect intestinal flora and the metabolic products in premature infants diagnosed as necrotizing enterocolitis. The main questions it aims to answer are:1. Whether there is intestinal flora in the stool of premature infants.2. Are there dysregulated intestinal flora and their metabolic products in premature infants diagnosed as necrotizing enterocolitis.3. The detailed role and underlying mechanism of the intestinal dysbacteriosis and the metabolic products in premature infants diagnosed as necrotizing enterocolitis.Participants, premature infants diagnosed as necrotizing enterocolitis (NEC group), will be asked to collect stool (usually 2 times) for intestinal flora analysis.If there is a comparison group: Researchers will compare premature infants without necrotizing enterocolitis (control group) to see if their intestinal flora and the metabolic products also changed as their NEC counterparts.

Inclusion Criteria:clinical diagnosis of Necrotizing Enterocolitis,gestational age <37 weeks,body weight 1,000-2,500 g,postnatal Apgar score ≥7,initial oral feeding tolerance.Exclusion Criteria:serious hereditary or other serious diseases, such as heart, lung and abdominal malformations ,early or late onset septicemia,early use of antibiotics in the newborn,serious adverse reactions caused by probiotics.