BACKGROUND A dramatic rise in the rate of clostridium difficile infection (CDI) in patients with inflammatory bowel disease (IBD) has been reported in recent years. METHODS In this observational case control study, 65 patients were included and were divided into two groups of IBD + CDI as case group and IBD without CDI as control group. RESULTS 35 patients who had positive test for clostridium difficile were assigned to the case group. The control group consisted of 30 patients with negative test for clostridium difficile. Pancolitis was seen in the cases more statistically significant than the controls and proctitis was seen more among the controls than the cases (p = 0.001). The cases were on immunosuppressive (p = 0.001) and antibiotic (p = 0.02) therapy more than the controls. Colonoscopic findings revealed more severe and extensive inflammation among the cases versus milder inflammation among the controls, but these differences were not statistically significant (p = 0.2). Colectomy was seen in 10% of controls and none of the cases and this difference was statistically significant (p value = 0.05). More fecal calprotectin were seen among the cases than the controls and this difference was statistically significant (p < 0.05) CONCLUSION This study showed more clostridium difficile infection among the patients on antibiotic or immunosuppressive therapy. Pathological investigation revealed more severe and extensive inflammation among the cases than the controls. Cases had clinically more severe signs and symptoms with higher mayo scores than the controls. ESR (Erythrocyte sedimentation rate) and fecal calprotectin were higher in patients with positive clostridium difficile infection and serum albumin was lower in such patients.