title: Increased immunoendocrine cells in intestinal mucosa of postinfectious irritable bowel syndrome patients 3 years after acute Shigella infection--an observation in a small case control study.
abstract: OBJECTIVE
  Postinfectiously irritable bowel syndrome (PI-IBS) develops in 3-30% of individuals with bacterial gastroenteritis. Recent studies demonstrated increases in inflammatory components in gut mucosa of PI-IBS patients even after complete resolution of infection. We aimed to investigate histological changes in colon and rectum of PI-IBS subjects after long term period of infection.
  
  
  METHODS
  We recruited PI-IBS subjects who had been diagnosed IBS after complete resolution of enteritis caused by shigellosis outbreak 3 years earlier. We compared unmatched four groups, PI-IBS (n = 4), non PI-IBS (n = 7), D-IBS (n = 7, diarrhea predominant type) and healthy controls (n = 10). All of them underwent colonoscopic biopsy at three areas, including descending colon (DC), sigmoid colon (SC) and rectum, which were assessed for 5-hydroxytryptamine (5-HT)/peptide YY (PYY)-containing enterochromaffin (EC) cell, intraepithelial (IEL) and lamina propria T lymphocyte (CD3), CD8 lymphocytes, mast cells and CD68/calprotectin+ macrophages.
  
  
  RESULTS
  All subjects had no structural or gross abnormalities at colonoscopy. In PI-IBS, 5-HT containing EC cells, PYY containing EC cells, IELs, CD3 lymphocytes, CD8 lymphocytes, mast cells, and CD68 + macrophages were increased compared to control (p < 0.05). In D-IBS, PYY containing EC cells, IELs, and CD3 lymphocytes were increased compared to control (p < 0.05). In PI-IBS, 5-HT containing EC cells tended to increase and PYY containing EC cells, CD8 lymphocytes, mast cells, and CD68+ macrophages were increased compared to non PI-IBS (p < 0.05). Calprotectin + marcrophages were decreased in PI-IBS, non PI-IBS and IBS compared to control.
  
  
  CONCLUSIONS
  The immunoendocrine cells were sporadically increased in PI-IBS, non PI-IBS and D-IBS compared with control. Our findings in a very small number of patients suggest that mucosal inflammation may play a role in long-term PI-IBS, and that other sub-groups of IBS and larger scale studies are needed to confirm this observation.
authors.affiliation: Department of Internal Medicine, Yonsei Institute of Gastroenterology, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Hee Sun
authors.initials: HS
authors.lastname: Kim
authors.forename: Jung Hyun
authors.initials: JH
authors.lastname: Lim
authors.forename: Hyojin
authors.initials: H
authors.lastname: Park
authors.forename: Sang In
authors.initials: SI
authors.lastname: Lee
mesh_terms: D000328:Adult; D015703:Antigens, CD / Q000378:metabolism; D015214:Antigens, Differentiation, Myelomonocytic / Q000378:metabolism; D018414:CD8-Positive T-Lymphocytes / Q000166:cytology; D016022:Case-Control Studies; D044683:Colon, Descending / Q000473:pathology; D012809:Colon, Sigmoid / Q000473:pathology; D003113:Colonoscopy; D004405:Dysentery, Bacillary / Q000150:complications*; D004759:Enterochromaffin Cells / Q000166:cytology; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D007413:Intestinal Mucosa / Q000473:pathology*; D043183:Irritable Bowel Syndrome / Q000378:metabolism / Q000473:pathology*; D008264:Macrophages / Q000166:cytology; D008297:Male; D008407:Mast Cells / Q000166:cytology; D019894:Peptide YY / Q000378:metabolism; D012007:Rectum / Q000473:pathology; D012701:Serotonin / Q000378:metabolism; D000097382:CD68 Molecule
chemical_list: D015703:Antigens, CD; D015214:Antigens, Differentiation, Myelomonocytic; D019894:Peptide YY; D012701:Serotonin; C067980:CD68 antigen, human; D000097382:CD68 Molecule