BACKGROUND AND AIMS: Bacterial gastroenteritis seems to be a risk factor of irritable bowel syndrome (IBS). The incidence of post-infectious IBS (PI-IBS) was reported to be in the range of 7-31%, but few studies have reported long term follow-up results. So, we investigated the clinical course and prognosis of PI-IBS three years after shigella infection. METHODS: The subjects were recruited from our previous study, in which we investigated the incidence and risk factors of PI-IBS. We had a questionnaire based on interview with 120 controls and 124 patients who had shigella infection three years ago. Both groups were evaluated for the presence of IBS, functional bowel disorders (FBD) except IBS before, one and three years after the infection, respectively. RESULTS: Ninty-five patients (76.6%) and 105 controls (87.5%) completed the questionnare. In patients group, 7 cases had IBS prior to infection (previous IBS), 12 cases (13.8%) had IBS after 1 year (PI-IBS). Four cases developed IBS newly after 3 years (new IBS). Thirteen cases (14.9%) in patients and 4 cases (4.5%) in controls had IBS over 3 years (OR 3.93: 1.20-12.86). The recovery rate over 3 years were 50.0% (2/4) in previous IBS and 25% (3/12) in PI-IBS. The incidence of PI-IBS after 3 years in previous FBD subjects was 28.6% and was 10.6% in normals (p<0.05). The female gender was a risk factor for FBD. CONCLUSIONS: Bacterial gastroenteritis is a trigger factor of IBS. About a quarter of PI-IBS patients are recovered over 3 years. Previous FBD except IBS is a risk factor after 3 years.
Adult ; Dysentery, Bacillary/*complications ; Female ; Follow-Up Studies ; Humans ; Irritable Bowel Syndrome/*etiology ; Male

PURPOSE: 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. MATERIALS AND 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. CONCLUSION: 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.
Adult ; Antigens, CD/metabolism ; Antigens, Differentiation, Myelomonocytic/metabolism ; CD8-Positive T-Lymphocytes/cytology ; Case-Control Studies ; Colon, Descending/pathology ; Colon, Sigmoid/pathology ; Colonoscopy ; Dysentery, Bacillary/*complications ; Enterochromaffin Cells/cytology ; Female ; Humans ; Immunohistochemistry ; Intestinal Mucosa/*pathology ; Irritable Bowel Syndrome/metabolism/*pathology ; Macrophages/cytology ; Male ; Mast Cells/cytology ; Peptide YY/metabolism ; Rectum/pathology ; Serotonin/metabolism