Phylogenetic Group of Escherichia coli Isolated from Inflammatory Bowel Disease in Al Najaf province

Background: Inflammatory Bowel Disease (IBD) is a chronic inflammatory condition of the gastrointestinal tract that includes Crohn's disease (CD) and ulcerative colitis. Recent studies have highlighted the role of specific bacterial species in the pathogenesis of IBD, including adherent-invasive Escherichia coli (AIEC). Objectives: The study was designed to determine the prevalence of Crohn's disease compared with ulcerative colitis, and determination the predominant bacterial species causing inflammatory bowel disease in Al-Najaf city, Additionally the study focused on molecular detection of the phylogenetic classification of E. coli by PCR. Methodology: The study collected 102 stool specimens were collected from inflammatory bowel disease patients . Escherichia coli isolates were diagnosed identified by culture and biochemical reactions. Vitek-2 compact system provides an automated final identification . the PCR approach was used for detecting the phylogenic groups by targeting three marker genes chuA and yjaA and DNA fragment TSPE4.C2. Result: Eighty eight isolates out of 102 (88%) were presumptively identified as Escherichia coli and 6 (5.88%) isolates identified as Pseudomonas spp and Klebsiella pneumoniae while 8 (7.84%) were negative growth. There were 90 cases diagnosed as Crohn's disease and only 12 cases diagnosed as ulcerative colitis. According to the results of PCR-based phylotyping, Phylogenetic group B2 (81.8%) was the most widely dispersed phylogenetic group of E. coli, followed by Phylogenetic group A (13.6%) and Phylogenetic group D (0.04%). Conclusion: Crohn's disease has a higher prevalence than ulcerative colitis. Phylogenetic group B2 Escherichia coli plays a significant role in inflammatory bowel disease pathogenesis by colonizing the gut and causing inflammation.