Background Gastrointestinal symptoms compatible with Irritable Bowel Syndrome (IBS) are common in patients with inflammatory bowel disease. It has been suggested that these symptoms are a reflection of occult inflammation rather than coexisting IBS. The aim of this study was to characterize IBS-like symptoms in patients with Ulcerative Colitis (UC) in clinical remission by assessing inflammatory markers, psychological symptoms, and quality of life. Methods Ninety-four patients with new onset of UC were followed prospectively during 3 years with yearly follow-up visits. The patients completed self-administrated questionnaires. Fecal calprotectin was used as an inflammatory biomarker. Remission was defined as a total Mayo-score ≤2 and an endoscopic subscore ≤1, with no relapse during the 3-month period prior to visit. Key Results The prevalence of patients that fulfilled Rome II criteria for IBS among UC patients in remission was 11% at visit 1, 23% at visit 2, and 17% at visit 3. When comparing UC patients in remission with and without IBS-like symptom, patients with IBS-like symptoms had more severe gastrointestinal symptoms, tendencies toward more severe psychological symptoms and reduced levels of quality of life, but the calprotectin levels did not differ between the two groups. Conclusions & Inferences IBS-like symptoms are common in patients with UC in clinical remission and these fluctuate over time. The symptoms are associated with poor psychological wellbeing and reduced quality of life, and do not seem to be a reflection of low-grade inflammatory activity.

IBS-like symptoms in patients with UC in deep remission are common, but not as prevalent as previously reported. Poor psychological well-being and increased serum cytokine levels, but not colonic low-grade inflammation, were associated with IBS-like symptoms.

Probable psychiatric disorder, iron deficiency, active disease and female gender are independent risk factors for high fatigue in patients with ulcerative colitis. Low-grade immune activity does not seem to be the cause of fatigue among patients in deep remission.