Many patients with inflammatory bowel disease (IBD) restrict dairy products to control their symptoms. The aim of the study was to investigate the prevalence of lactose intolerance assessed with hydrogen breath test (H-BT) in IBD patients in clinical remission compared to a sex, age and BMI matched control population. We further detected the prevalence of three single nucleotide polymorphisms of the lactase (LCT) gene: the lactase non persistence LCT-13910 CC (wildtype) and the intermediate phenotype LCT-22018 CT and LCT-13910 AG; finally, we assess the correlation between genotype and H-BT. A total of 54 IBD patients and 69 control who underwent clinical evaluation, H-BT and genetic test were enrolled. H-BT was positive in 64.8% IBD patients and 62.3% control (p = 0.3). The wild-type genotype was found in 85.2% IBD patients while CT-22018, AG-13910 and CT-22018/AG-13910 polymorphisms were found in 9.3%, 1.8% and 3.7%. In the control group, the wild-type genotype, CT-22018, AG-13910 and CT-22018/AG-13910 polymorphisms were found in 87%, 5.8%, 5.8% and 1.4% of cases, respectively. Therefore, the wild-type and polymorphisms’ prevalence did not differ between IBD population and control group (85.2% vs. 87%, p = 0.1) (14.8% vs. 13%, p = 0.7). The correlation between positive H-BT and genetic analysis showed that the wild-type genotype was associated with higher rate of lactose intolerance in the total population (OR 5.31, 95%CI 1.73–16.29, p = 0.003) and in the IBD (OR 7.61, 95%CI 1.36–42.7, p = 0.02). The prevalence of lactose intolerance in IBD patients did not differ from that of control. Despite suggestive symptoms, about 1/3 of IBD patients are not lactose intolerant, thus not needing “a priori” elimination diet. This may encourage a rationale and balanced dietary management in IBD.

(normal stool frequency and cessation of bleeding; pts’ diaries). Normal stool frequency (UC-DAI stool frequency subscore 0), clinical remission (abbreviated UC-DAI score 0), treatment failure (need for disallowed treatments), and non-bleeding stools (UC-DAI rectal bleeding subscore 0) at week 4 were also analysed. Observed case analyses are shown. Categorical variables were analysed by Cochran-Mantel Haenszel chisquared test and time-to-endpoint variables by Cox survival analysis, all adjusted by country. Results: 206 pts were enrolled and 202 included in intent-totreat analyses (n = 101 per arm). OD 5-ASA was superior to BD for mucosal healing at week 8 (87.5% vs 71.1% respectively; difference 16.4% [CIs 4.5 28.2]; P= 0.007). Median time to remission was significantly shorter with OD vs BD dosing (26 vs 28 days, respectively; P= 0.042). Time to cessation of bleeding was not significantly different (13 vs 21 days, respectively; P= 0.139). At week 4, significantly more pts had normal stool frequency with OD vs BD dosing (P= 0.013); there was no significant difference in rates of clinical remission, treatment failure or non-bleeding stools. Conclusions: 4 g OD 5-ASA was non-inferior to BD dosing. Moreover, significantly more pts with active UC achieved mucosal healing at week 8 and normal stool frequency at week 4 with 4 g 5-ASA OD vs BD, and median time to remission was significantly shorter with OD therapy. Other secondary endpoints were similar with OD and BD dosing at week 4. These data are consistent with those seen for maintenance of remission, and suggest that OD Pentasa® offers potential benefits to pts.