Rate of microscopic colitis and cytokine levels in patients with irritable bowel syndrome

Abstract

Aims: The aim of this study is to determine the rate of microscopic colitis (MC) among patients diagnosed as Irritable Bowel Syndrome (IBS) in accordance with Roma III criteria and to investigate the correlation of cytokine levels with the type of IBS and presence of MC. Methodology: A total of Eighty-nine patients who were diagnosed with IBS based on Rome III diagnostic criteria were included in this study. Biopsies taken from caecum, ascending colon, transverse colon, descending colon and rectosigmoid region during colonoscopy were put in separate tubes and histopathologically examined. In addition, serum TNF-?, IL-1? and IL-6 levels were determined in peripheral blood samples of patients. Results: The frequency of MC was higher in the study groups compared to the general population (22.5% and 20.4% in IBS-D and IBS-C groups, respectively). Specimens taken from caecum, ascending colon, transverse colon and descending colon were more likely to lead to the diagnosis of MC compared to those taken from rectrosigmoid region (p<0.001). No significant difference was found between presence of MC and IL-1?, IL-6 and TNF-? levels. In addition, TNF-? levels were significantly higher in the IBS-C group (p= 0.013). Conclusion: Rate of MC in IBS patients is higher than the rate in normal population. In IBS patients, biopsy samples obtained solely from rectosigmoid area is not sufficient to preclude MC diagnosis. No difference exists between IBS patients with and without MC in terms of cytokine levels.