臨床消化器病学ジャーナル

Due to recent changes in EU regulations (2010/63/EU) as well as the general requirement to assess the condition of experimental laboratory animals, the development of innovative severity assessment strategies is required. In murine inflammatory bowel disease (IBD) models severity assessment is usually performed by clinical scoring, which is time consuming, stressful for the animals, and necessitates an experienced observer. This mini review looks at methods to identify disturbed animal welfare during experimental colitis by investigating changes in spontaneous animal behavior. We give a brief overview of the existing methods of severity assessment utilized in colitis models, focusing on a recently investigated method, the time to integrate to nest test (TINT). In a study investigating the course of colitis in genetically-susceptible and corresponding wild type mice, the suitability of TINT as a parameter of disturbed welfare was determined. TINT enabled the detection of mouse strain-related differences, but not dextran sulphate sodium (DSS) dose-dependent differences in colitis manifestation. Therefore, TINT may serve as an easily applicable indicator of disturbed animal welfare but cannot replace clinical investigation of animals under experimentation. The development of further severity assessment strategies that better mirror the actual condition of animals used in IBD studies is therefore vital.

Objective: It is unclear whether the initial surgical rate for CD in Japan has decreased. The present study investigated time trend of background factors and risk factors of initial surgery for CD patients. Methods: A total of 424 patients diagnosed with CD in our department over the last 20 years who had not undergone surgery were analyzed. The cumulative initial surgery rate was determined using the Kaplan-Meier method. Patients were analyzed to identify risk factors for initial intestinal surgery. Patients diagnosed between 1992 and 2001 were classified into the pre-biological era group (PRE) (n=248), and those diagnosed between 2002 and 2011 into the post-biological era group (POST) (n=176). The groups were compared regarding background factors and reason for initial surgery. Results: The patients included 303 men and 121 women and a mean length of follow-up of 5.5 ± 4.8 years. The comparison of background characteristics between the PRE group and the POST group for each factor demonstrated a significant increase in inflammatory Crohn’s disease in the POST group (47.6% vs. 61.9%; p=0.007). Cumulative initial surgery rates by era did not differ between the two groups, at 21.0% and 30.5% at 3 and 5 years, respectively, in the PRE group and 26.7% and 38.5% at 3 and 5 years, respectively, in the POST group. However, the surgery rate in patient with biologics treatment such as infliximab and adalimumab was significantly lower than that of patient without biologics at 5 year (8.6% vs. 37.9%; p