RESUMO
Introduction: Irritable bowel syndrome (IBS), though abenign disorder is highly prevalent and imposes high costand substantial morbidity upon general population. Longconsidered as functional disorder, IBS pathogenesis carries anorganic basis at least in a subset of patients. Altered intestinalimmune response and low grade intestinal inflammation havebeen confirmed as pathophysiology of IBS in few studies.Oxidative stress indicates that there is inflammation and,markers of oxidative stress may be developed as diagnostictool for IBS in future. Study aimed to evaluate oxidativestress in form of total oxidant status (TOS), total anti-oxidantstatus (TAS), oxidative stress index (OSI) and serum prolidaseactivity (SPA) as a marker of intestinal inflammation in IBSpatients and healthy controls.Material and methods: In this case –control study done ata teaching medical institute in north India over a period ofone year, 120 IBS patients (cases) and 40 healthy volunteers(controls) were evaluated for TOS, TAS, OSI and SPA.Patients with IBS were sub-divided into 3 groups (40 each):diarrhea predominant, constipation predominant and mixedtype (IBS-D, C and M respectively). Student t-test, chi-squaretest and ANOVA tests were used for statistical analysis.Results: Mean TOS, TOS/TAS (OSI) and prolidase levelswere significantly higher in IBS group than control with pvalue of <0.001,< 0.001, and <0.01 respectively. Level ofTOS was highest in IBS-D subgroup followed by IBS-M andLowest in IBS-C subgroup showing a significant differencebetween IBS-D and IBS-C, IBS-D and IBS-M and IBS-Mand IBS-C with p values <0.001 for each comparison. OSIwas highest in IBS-D and lowest in IBS-C with significantdifferences between the subgroups (P<0.001). Only IBS-Msubgroup had significantly higher serum prolidase activitywhen compared to controls (p<0.001) IBS-D (P=0.013) andIBS-C (P=0.01). TAS level was significantly higher in controls(P<0.001) than cases. There were significant differencesbetween all four subgroups (p<0.001) except between IBS-Cand IBS-M subgroups (P=0.294).Conclusion: This study observed that there is increasedoxidative stress and decreased antioxidant capacity in patientwith IBS. To support our results further prospective andrandomized controlled trials are necessary.