Steroid-refractory extensive enteritis complicated by ulcerative colitis successfully treated with adalimumab

Extracolonic involvement of the gastrointestinal tract is extremely uncommon in ulcerative colitis (UC) and rarely found in the upper gastrointestinal tract or in postoperative cases since it typically responds to steroids. Here we report a case of UC complicated by extensive ileal inflammation that was refractory to steroids. A 20-year-old man was diagnosed with UC of typical pancolitis without ileal involvement and started treatment with pH-dependent mesalazine and oral prednisolone. Although his symptoms transiently resolved, the condition flared when the steroid dose was tapered down. Computed tomography revealed marked thickening of the ileal wall, and capsule endoscopy and balloon-assisted enteroscopy found diffuse mucosal inflammation with ulcers in the ileum. On the contrary, the inflammation in the colon and rectum was improving. Since the response to the second steroid course was inadequate, treatment with adalimumab and 6-mercaptopurine was initiated and finally achieved clinical and endoscopic remission. The investigation of small intestinal lesions is necessary in patients with UC whose clinical deterioration cannot be explained by colonic lesions

Risk of venous thromboembolism with a central venous catheter in hospitalized Japanese patients with inflammatory bowel disease: a propensity score-matched cohort study

Background/Aims Thromboprophylaxis is recommended for hospitalized patients with inflammatory bowel disease (IBD) in Western countries, although it is selectively administered to high-risk patients in East Asia. A central venous catheter (CVC) is commonly placed in patients with IBD. Although CVC placement is considered a risk factor for venous thromboembolism (VTE), the degree of increased risk in patients with IBD is uncertain. This study aimed to identify the risk of VTE with CVC placement in hospitalized Japanese patients with IBD without thromboprophylaxis. Methods This retrospective cohort study included patients with ulcerative colitis or Crohn’s disease who were admitted for disease flares at Keio University Hospital between January 2016 and December 2020. Patients who already had thrombosis or were administered any antithrombotic treatment on admission were excluded. VTE development during the hospitalization was surveyed, and VTE risk associated with CVC indwelling was estimated using propensity score matching and inverse probability of treatment weighting analyses. Results Altogether, 497 hospitalized patients with IBD (ulcerative colitis, 327; Crohn’s disease, 170) were enrolled. VTE developed in 9.30% (12/129) of catheterized patients and in 0.82% (3/368) of non-catheterized patients. The propensity score matching yielded 127 matched pairs of patients. The catheterized group demonstrated higher odds for VTE than the non-catheterized group (odds ratio, 13.15; 95% confidence interval, 1.68–102.70). A similar result was obtained in the inverse probability of treatment weighting analysis (odds ratio, 11.02; 95% confidence interval, 2.64–46.10). Conclusions CVC placement is a major risk factor for VTE among hospitalized Japanese patients with IBD without thromboprophylaxis

Macrophages and dendritic cells emerge in the liver during intestinal inflammation and predispose the liver to inflammation.

The liver is a physiological site of immune tolerance, the breakdown of which induces immunity. Liver antigen-presenting cells may be involved in both immune tolerance and activation. Although inflammatory diseases of the liver are frequently associated with inflammatory bowel diseases, the underlying immunological mechanisms remain to be elucidated. Here we report two murine models of inflammatory bowel disease: RAG-2(-/-) mice adoptively transferred with CD4(+)CD45RB(high) T cells; and IL-10(-/-) mice, accompanied by the infiltration of mononuclear cells in the liver. Notably, CD11b(-)CD11c(low)PDCA-1(+) plasmacytoid dendritic cells (DCs) abundantly residing in the liver of normal wild-type mice disappeared in colitic CD4(+)CD45RB(high) T cell-transferred RAG-2(-/-) mice and IL-10(-/-) mice in parallel with the emergence of macrophages (Mφs) and conventional DCs (cDCs). Furthermore, liver Mφ/cDCs emerging during intestinal inflammation not only promote the proliferation of naïve CD4(+) T cells, but also instruct them to differentiate into IFN-γ-producing Th1 cells in vitro. The emergence of pathological Mφ/cDCs in the liver also occurred in a model of acute dextran sulfate sodium (DSS)-induced colitis under specific pathogen-free conditions, but was canceled in germ-free conditions. Last, the Mφ/cDCs that emerged in acute DSS colitis significantly exacerbated Fas-mediated hepatitis. Collectively, intestinal inflammation skews the composition of antigen-presenting cells in the liver through signaling from commensal bacteria and predisposes the liver to inflammation

Toll-Like Receptor 7 Agonist–Induced Dermatitis Causes Severe Dextran Sulfate Sodium Colitis by Altering the Gut Microbiome and Immune CellsSummary

Background & Aims: Psoriasis and inflammatory bowel disease (IBD) are both chronic inflammatory diseases occurring in the skin and gut, respectively. It is well established that psoriasis and IBD have high concordance rates, and similar changes in immune cells and microbiome composition have been reported in both conditions. To study this connection, we used a combination murine model of psoriatic dermatitis and colitis in which mice were treated topically with the Toll-like receptor 7 agonist imiquimod (IMQ) and fed dextran sulfate sodium (DSS). Methods: We applied IMQ topically to B6 mice (IMQ mice) and subsequently fed them 2% DSS in their drinking water. Disease activity and immune cell phenotypes were analyzed, and the microbial composition of fecal samples was investigated using 16S ribosomal RNA sequencing. We transplanted feces from IMQ mice to germ-free IQI/Jic (IQI) mice and fed them DSS to assess the effect of the gut microbiome on disease. Results: We first confirmed that IMQ mice showed accelerated DSS colitis. IMQ mice had decreased numbers of IgD+ and IgM+ B cells and increased numbers of non–cytokine-producing macrophages in the gut. Moreover, the gut microbiomes of IMQ mice were perturbed, with significant reductions of Lactobacillus johnsonii and Lactobacillus reuteri populations. Germ-free mice transplanted with feces from IMQ mice, but not with feces from untreated mice, also developed exacerbated DSS colitis. Conclusions: These results suggest that skin inflammation may contribute to pathogenic conditions in the gut via immunologic and microbiological changes. Our finding of a novel potential skin–gut interaction provides new insights into the coincidence of psoriasis and IBD. Keywords: Inflammatory Bowel Disease, Dermatitis, Gut Microbiom