Correlation between Intestinal Microflora in Irritable Bowel Syndrome and Severity

Background. Irritable bowel syndrome (IBS) is a common chronic functional gastrointestinal disease accompanied by changes in intestinal microecology. This study investigated the relationship between gut microbiota and disease severity in patients with irritable bowel syndrome (IBS). Methods. An observational study was performed on 60 IBS patients (study group) and 20 healthy controls admitted to our hospital from January 2013 to December 2014. Fecal samples were taken after admission to measure intestinal flora including Bifidobacterium, Lactobacillus, Enterobacter, and Enterococcus, and patient blood was collected to determine serum D-lactate and diamine oxidase (DAO) levels. The gut microbiota and serum markers of the two groups were analyzed. The correlation of gut microbiota index levels and serum markers with disease severity, as well as the correlation between gut microbiota index levels and serum markers, were analyzed. Results. The levels of intestinal Lactobacillus and Bifidobacterium were lower, while the levels of Enterococcus and Enterobacter and serum D-lactate were higher in the study group than those in the control group. The levels of intestinal Lactobacillus and Bifidobacterium were lower, while the levels of Enterococcus and Enterobacter, serum D-lactate, and DAO were higher in patients with moderate IBS than those in patients with mild IBS. The levels of intestinal Lactobacillus and Bifidobacterium were lower in patients with severe IBS than those with moderate IBS, while the levels of Enterococcus and Enterobacter, serum D-lactate, and DAO were higher in patients with severe IBS. There was a significant negative correlation between the levels of Lactobacillus and Bifidobacterium and disease severity and a significant positive correlation between the levels of Enterococcus and Enterobacter, D-lactate, and DAO and disease severity. There was a significant negative correlation between the levels of Lactobacillus and Bifidobacterium and serum D-lactate and DAO, while there was a significant positive correlation between the levels of Enterococcus and Enterobacter and serum D-lactate and DAO ( $P<0.05$ ). Conclusion. Intestinal flora, D-lactate, and DAO were abnormal in IBS patients, and intestinal flora was closely correlated with disease severity, D-lactate, and DAO levels.