[Report on a new remote collaborative medical care system -construction and operation of a remote collaborative medical care network for inflammatory bowel disease using information and communication technology in Hokkaido].

Inflammatory bowel disease (IBD) comprises 2 major types-ulcerative colitis (UC) and Crohn's disease (CD). A remote collaborative medical care fee has been established for patients with suspected intractable diseases since 2020. Remote collaborative medical care is a type of telemedicine wherein a hospital specialist for intractable diseases, the patient, and an attending physician at a community hospital communicate via video calls. In IBD cases, however, treating patients who have already been diagnosed with severe or intractable diseases is difficult. As a part of the Hokkaido Intractable Disease Medical Care System Development Project, we have started providing free remote collaborative medical care services for all IBD patients, including those with a confirmed diagnosis and attending regional hospitals. We set up the telemedicine system using Microsoft365, a commercial cloud, and Nextcloud, a PaaS, to ensure robust security and enable rapid and massive sharing of medical details by information and communication technology. Since April 2021, we have examined 27 patients (36 times). Among these patients, 5 patients from regional hospitals were undiagnosed (1 patient of suspected CD, 3 patients of suspected IBD unclassified (IBD-U), and 1 patient of undiagnosed enteritis). Twenty-two patients from regional hospitals had a confirmed diagnosis (17 UC and 5 CD patients). Eight patients required a second time remote collaborative medical care, and 1 patient required a third time remote collaborative medical care. There was no equipment failure such as communication failure or system trouble, and all patients could be examined smoothly. The maintenance cost of the telemedicine system was 2500yen/month per hospital. Among all cases receiving remote collaborative medical care, 86% were consultations for refractory or severe active cases with a confirmed diagnosis of IBD. At present, the remote collaborative medical care fee for diagnosed patients is not permitted. Since remote collaborative medical care has the potential to correct regional disparities in medical standards, there is an urgent need to review the criteria for remote collaborative medical care fees.

Expert Opinions on the Current Therapeutic Management of Inflammatory Bowel Disease during the COVID-19 Pandemic: Japan IBD COVID-19 Taskforce, Intractable Diseases, the Health and Labor Sciences Research.

BACKGROUND: The COVID-19 pandemic, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has emerged as a dramatic challenge for all healthcare systems worldwide. This outbreak immediately affected gastroenterologists as well as global physicians worldwide because COVID-19 can be associated with not only triggering respiratory inflammation but also gastrointestinal (GI) inflammation based on the mechanism by which SARS-CoV-2 enters cells via its receptor the angiotensin-converting enzyme 2, which is expressed on GI cells. However, the comorbidity spectrum of digestive system in patients with COVID-19 remains unknown. Because the inflammatory bowel disease (IBD) management involves treating uncontrolled inflammation with immune-based therapies, physicians, and patients have great concern about whether IBD patients are more susceptible to SARS-CoV-2 infection and have worsened disease courses. SUMMARY: It is necessary to precisely ascertain the risk of SARS-CoV-2 infection and the COVID-19 severity in IBD patients and to acknowledge the IBD management during the COVID-19 pandemic with clinically reliable information from COVID-19 cohorts and IBD experts' opinions. In this review, we highlight clinical questions regarding IBD management during the COVID-19 pandemic and make comments corresponding to each question based on recent publications. Key Messages: We propose that there is (1) no evidence that IBD itself increases the risk of SARS-CoV-2 infection, (2) to basically prioritize the control of disease activity of IBD, (3) no need for physicians to suddenly discontinue immunomodulatory or biologic therapy in patients with quiescent IBD, and (4) a need for careful observation of elderly (>60 years old) and IBD patients receiving corticosteroid treatment during the COVID-19 pandemic.

Artificial intelligence-assisted endoscopy changes the definition of mucosal healing in ulcerative colitis.

The relevance of endoscopic monitoring of ulcerative colitis (UC) has been translated into the new concept of "mucosal healing (MH)" as the therapeutic goal to achieve because a large amount of scientific data have revealed the favorable prognostic value of a healed mucosa in determining the clinical outcome of UC. Recent interest in MH has skewed toward not only endoscopic remission but also histological improvement (so called histological MH). However, we should recognize that there have been no prospectively validated endoscopic scoring systems of UC activity in previous clinical trials. Artificial intelligence (AI)-assisted endoscopy has been developed for gastrointestinal cancer surveillance. Recently, several AI-assisted endoscopic systems have been developed for assessment of MH in UC. In the future, the development of a new endoscopic scoring system based on AI might standardize the definition of MH. Therefore, "The road to an exact definition of MH in the treatment of UC has begun only now".

Immunological Mechanisms in Inflammation-Associated Colon Carcinogenesis.

Patients with chronic inflammatory bowel diseases are at an increased risk of developing colitis-associated cancer (CAC). Chronic inflammation positively correlates with tumorigenesis. Similarly, the cumulative rate of incidence of developing CAC increases with prolonged colon inflammation. Immune signaling pathways, such as nuclear factor (NF)-κB, prostaglandin E2 (PGE2)/cyclooxygenase-2 (COX-2), interleukin (IL)-6/signal transducer and activator of transcription 3 (STAT3), and IL-23/T helper 17 cell (Th17), have been shown to promote CAC tumorigenesis. In addition, gut microbiota contributes to the development and progression of CAC. This review summarizes the signaling pathways involved in the pathogenesis following colon inflammation to understand the underlying molecular mechanisms in CAC tumorigenesis.

Current Diagnostic and Therapeutic Approaches to Cytomegalovirus Infections in Ulcerative Colitis Patients Based on Clinical and Basic Research Data.

Human cytomegalovirus (HCMV) is a ubiquitous herpesvirus (the human herpesvirus 5) and an opportunistic pathogen that primarily infects HIV-positive and other immuno-compromised patients. Retrospective studies in the field of inflammatory bowel disease (IBD) have suggested a relationship between a concomitant colonic HCMV infection and poor outcomes in patients with an ulcerative colitis (UC) due to the presence of HCMV in surgical specimens of patients with a toxic megacolon or a steroid-resistant UC. Therefore, gastroenterologists have focused on the contribution of HCMV infections in the exacerbation of UC. Numerous studies have addressed the benefits of treating colonic HCMV reactivation in UC using an antiviral treatment. However, its clinical relevance remains uncertain as only a few prospective studies have assessed the direct relationship between clinical outcomes and the viral load of HCMV in colonic tissues. HCMV reactivation can be triggered by inflammation according to fundamental research studies. Thus, optimal control of intestinal inflammation is essential for preventing an HCMV reactivation in the intestinal mucosa. Indeed, several reports have indicated the effectiveness of an anti-tumor necrosis factor-alpha (TNFα) treatment in patients with an active UC and concomitant HCMV infections. In this review, we describe the mechanism of HCMV reactivation in UC cases and discuss the current issues regarding diagnosis and treatment of HCMV infections in UC patients.

Autophagy and Autophagy-Related Diseases: A Review.

Autophagy refers to the process involving the decomposition of intracellular components via lysosomes. Autophagy plays an important role in maintaining and regulating cell homeostasis by degrading intracellular components and providing degradation products to cells. In vivo, autophagy has been shown to be involved in the starvation response, intracellular quality control, early development, and cell differentiation. Recent studies have revealed that autophagy dysfunction is implicated in neurodegenerative diseases and tumorigenesis. In addition to the discovery of certain disease-causing autophagy-related mutations and elucidation of the pathogenesis of conditions resulting from the abnormal degradation of selective autophagy substrates, the activation of autophagy is essential for prolonging life and suppressing aging. This article provides a comprehensive review of the role of autophagy in health, physiological function, and autophagy-related disease.

[Primary biliary cholangitis complicated by primary hepatic extranodal marginal zone lymphoma of mucosa-associated lymphoid tissue].

An 89-year-old woman was admitted to our hospital owing to liver dysfunction and ascites. Enhanced computed tomography (CT) revealed hepatomegaly and heterogeneous density in the liver. 18F-fluorodeoxyglucose-positron emission tomography (FDG-PET) /CT revealed diffuse accumulation of FDG throughout the liver. Histopathology of a biopsy specimen revealed hepatic mucosa-associated lymphoid tissue (MALT) lymphoma. Complete remission (CR) was achieved with two cycles of rituximab, pirarubicin, cyclophosphamide, vincristine, and prednisolone. Because a second CT demonstrated liver cirrhosis and a test for anti-mitochondrial antibody was positive, liver biopsy was repeated, and pathological examination confirmed primary biliary cholangitis (PBC). The lymphoma recurred after 18 months and was treated with rituximab, which again resulted in CR. Over the subsequent 7 years, the patient had no liver dysfunction or recurrent lymphoma. Interestingly, despite the underlying PBC, liver dysfunction in this case appeared only with the MALT lymphoma.

A case of adenosquamous carcinoma of the lower bile duct diagnosed preoperatively via transpapillary biopsy.

A 78-year-old man presented to our hospital with fever and brownish urine. Upon thorough examination, a diagnosis of obstructive jaundice and acute cholangitis associated with a lower bile duct tumor was made. Endoscopic retrograde cholangiopancreatography revealed entire circumferential stenosis of the lower bile duct. Examination of a transpapillary biopsy specimen of the lesion suggested adenosquamous carcinoma. The patient underwent subtotal stomach-preserving pancreaticoduodenectomy. Histopathological examination revealed adenocarcinoma of the lower bile duct and squamous cell carcinoma components;a case of adenosquamous carcinoma was accordingly diagnosed. The lower bile duct tumor directly extended into the pancreatic parenchyma for approximately 1mm. We performed radical surgery and administered adjuvant chemotherapy with gemcitabine because of advanced neural invasion after consulting with the patient. There was no sign of recurrence 46 months after surgery. As adenosquamous carcinoma of the extrahepatic bile duct is rare, it is difficult to preoperatively diagnose the condition. Only a few cases have been reported till date.

Identification of relapse predictors in IgG4-related disease using multivariate analysis of clinical data at the first visit and initial treatment.

OBJECTIVES: Inducting clinical remission by glucocorticoid treatment is relatively easy in IgG4-related disease (IgG4-RD), but relapse also occurs easily with tapering of the steroid dose. The present study tried to analyse the cases to extract predictors of relapse present at the diagnosis of IgG4-RD. METHODS: Subjects comprised 79 patients with IgG4-related dacryoadenitis and sialadenitis, known as Mikulicz's disease, who were diagnosed between April 1997 and October 2013 and followed-up for >2 years from the initial induction treatment. They were applied to Cox proportional hazard modelling, based on the outcome of interval to relapse. We performed multivariate analysis for the clinical factors of these cases and identified predictors of relapse. RESULTS: Identified factors were male sex and younger onset in cases without organ involvement at diagnosis and low levels of serum IgG4 in cases with organ dysfunction at diagnosis. Complication with autoimmune pancreatitis and low steroid dose at initial treatment also tended to be associated with recurrence. CONCLUSION: Follow-up is important in cases with recognized risk factors for relapse, including male sex and younger onset in cases without organ damage.

CCAAT/enhancer binding protein α (C/EBPα)(+) M2 macrophages contribute to fibrosis in IgG4-related disease?

IgG4-related disease (IgG4-RD) is a new disease entity characterized by type 2 helper T (Th2)-dominant inflammation and progressive fibrosis. We found the infiltration of strange cell populations in the fibrotic lesions of submandibular gland specimens obtained from 15 patients with IgG4-RD. These cells expressed CCAAT/enhancer binding protein a (C/EBPα). Many of the cell populations were identified with M2 macrophages. The degrees of infiltration of C/EBPα(+)M2 macrophages and the ratio of fibrotic lesions in the specimens were correlated (r(2) = 0.83, p < 0.01). We also analyzed the expression of C/EBPα in other chronic inflammatory disorders: synovium in rheumatoid arthritis (RA), liver tissue in chronic viral hepatitis, and mucosa in ulcerative colitis. The specimens from RA and chronic viral hepatitis showed infiltration of C/EBPα(+) cells, but there were few C/EBPα-positive cells in ulcerative colitis. Fibrosis is not a major issue in ulcerative colitis. In conclusion, we found the remarkable infiltration of C/EBPα(+)M2 macrophages in cases of chronic inflammation with fibrosis, including IgG4-RD. This primitive study also disclosed that most of C/EBPα(+)M2 macrophages localized in fibrotic lesions, and the degree of the infiltration and the ratio of fibrotic area were correlated.

Everyday clinical practice in IgG4-related dacryoadenitis and/or sialadenitis: results from the SMART database.

Abstract Objective. Immunoglobulin (Ig)G4-related disease (IgG4-RD) is a new disease entity that has only been identified this century. Clinical information is thus lacking. We established the Sapporo Medical University and Related Institutes Database for Investigation and Best Treatments of IgG4-related Disease (SMART) to clarify the clinical features of IgG4-RD and provide useful information for clinicians. Methods. Participants comprised 122 patients with IgG4-related dacryoadenitis and/or sialadenitis (IgG4-DS), representing lacrimal and/or salivary lesions of IgG4-RD, followed-up in December 2013. We analyzed the sex ratio, mean age at onset, organ dysfunction, history or complications of malignancy, treatments, rate of clinical remission, and relapse. Results. The sex ratio was roughly equal. Mean age at diagnosis was 59.0 years. Positron emission tomography revealed that the ratio of other organ involvements was 61.4%. Complications of malignancy were observed in 7.4% of cases. Glucocorticoid was used to treat 92.1% of cases, and the mean maintenance dose of prednisolone was 4.8 mg/day. Rituximab was added in three cases, and showed good steroid-sparing effect. The clinical remission rate was 73.8%, and the annual relapse rate was 11.5%. Half of the cases experienced relapses within 7 years of initial treatment. Conclusion. We analyzed the clinical features and treatments of IgG4-DS using SMART, providing useful information for everyday clinical practice.

Cytokine Profile in Predicting the Effectiveness of Advanced Therapy for Ulcerative Colitis: A Narrative Review.

Cytokine-targeted therapies have shown efficacy in treating patients with ulcerative colitis (UC), but responses to these advanced therapies can vary. This variability may be due to differences in cytokine profiles among patients with UC. While the etiology of UC is not fully understood, abnormalities of the cytokine profiles are deeply involved in its pathophysiology. Therefore, an approach focused on the cytokine profile of individual patients with UC is ideal. Recent studies have demonstrated that molecular analysis of cytokine profiles in UC can predict response to each advanced therapy. This narrative review summarizes the molecules involved in the efficacy of various advanced therapies for UC. Understanding these associations may be helpful in selecting optimal therapeutic agents.

Gut microbiota and metabolites in patients with COVID-19 are altered by the type of SARS-CoV-2 variant.

Introduction: Patients with COVID-19 have dysbiosis of the intestinal microbiota with altered metabolites in the stool. However, it remains unclear whether the differences among SARS-CoV-2 variants lead to differences in intestinal microbiota and metabolites. Thus, we compared the microbiome and metabolome changes for each SARS-CoV-2 variant in patients with COVID-19. Materials and methods: We conducted a multicenter observational study of patients with COVID-19 and performed fecal microbiome, metabolome, and calprotectin analyses and compared the results among the different SARS-CoV-2 variants. Results: Twenty-one patients with COVID-19 were enrolled and stratified according to the SARS-CoV-2 strain: six with the Alpha, 10 with the Delta, and five with the Omicron variant. Fecal microbiome analysis showed that α-diversity was reduced in the order of the Omicron, Delta, and Alpha variants (p = 0.07). Linear discriminant analysis revealed differences in the abundance of short-chain fatty acid-producing gut microbiota for each SARS-CoV-2 variant. Fecal metabolome analysis showed that the Omicron and Delta variants had markedly reduced propionic and lactic acid levels compared to the Alpha strain (p < 0.05). Conclusion: The intestinal microbiota of patients with COVID-19 varies depending on the SARS-CoV-2 variant. Dysbiosis of the intestinal microbiota due to differences in SARS-CoV-2 variants causes a decrease in intestinal short-chain fatty acids.

Clinical performance of fecal calprotectin, lactoferrin, and hemoglobin for evaluating the disease activity of IBD and detecting colorectal tumors.

Background and Aim: Recently, noninvasive fecal markers have been used as indicators of intestinal inflammation in patients with inflammatory bowel disease (IBD). We conducted a clinical validation study to measure fecal calprotectin (Cp), lactoferrin (Lf), and hemoglobin (Hb) levels using an all-in-one kit in patients with IBD and colorectal tumors and aimed to clarify the utility of these fecal markers. Methods: In this study, 104 patients were analyzed, including 25 patients with ulcerative colitis (UC), 20 with Crohn's disease (CD), 48 with colorectal tumors, and 13 healthy controls (HC). Of the 48 patients with colorectal tumors, 14 had invasive cancer. We validated the utility of fecal Cp, Lf, and Hb levels by simultaneously measuring fecal markers in patients with IBD and colorectal tumors. Results: Fecal Cp and Lf had almost equivalent abilities in detecting clinical remission in patients with UC; however, fecal Cp was slightly superior to Lf. Regarding colorectal tumors, fecal Cp and Lf levels tended to be higher in patients with adenomas and colorectal cancer than in HCs. Although fecal Hb alone had the best sensitivity and specificity for detecting colorectal cancer, it had relatively low sensitivity for detecting advanced neoplasms and colorectal cancer. Conclusion: Fecal Cp and Lf can be used as almost equivalent biomarkers to assess the clinical activity in patients with UC. Fecal Hb is the most useful marker for screening colorectal cancer; however, adding fecal Cp and Lf may compensate for the low sensitivity of detecting for advanced colorectal tumors based on Hb alone.

Effectiveness and Persistency of Ustekinumab Treatment for Ulcerative Colitis: A Phoenix retrospective Cohort Study.

Background: Real-world data regarding ustekinumab (UST) for ulcerative colitis (UC) particularly in biologics-naïve patients is currently limited. This study aimed to elucidate the real-world effectiveness and safety of UST for UC. Methods: Overall, 150 patients with UC treated with UST from March 2020 to January 2023 were enrolled across 7 referral hospitals. To assess the clinical efficacy and persistence of UST, retrospective analyses were conducted from weeks 8 to 56. Predictive factors concerning the response and persistence of UST were examined through univariate and multivariate analyses. Results: Of the 150 patients, 125 received UST for remission induction, including 36% biologics-naïve. The response and remission rates were 72.8% and 56.0% at week 8 and 73.2% and 63.4% at week 56, respectively. Biologics-naïve patients represented higher response and remission rates at week 8 (84.4% and 73.3%) than those with biologics exposure (66.2% and 46.2%). Patients with prior antitumor necrosis factor (anti-TNF) and vedolizumab (VDZ) exposure had relatively lower response and remission rates (34.5% and 24.1%, respectively). The 1-year cumulative persistence rate was 84.0%. Multivariate analysis revealed that the chronic continuous type and prior anti-TNF and VDZ exposure were negative predictive factors for week 8 responsiveness. Clinical response at week 8 was a predictor of 1-year persistence. Adverse event incidence remained notably low at 6.4%. Conclusions: This study highlights the safety and effectiveness of UST as an induction and maintenance therapy for UC. Chronic continuous type and previous anti-TNF and VDZ exposure negatively contributed to short-term effectiveness, whereas short-term effectiveness provided good persistency.

Application of plasma alternative to serum for measuring leucine-rich α2-glycoprotein as a biomarker of inflammatory bowel disease.

BACKGROUND: Inflammatory bowel disease (IBD) is a chronic intestinal disorder characterized by recurrent flare-ups and remission. Leucine-rich α2-glycoprotein (LRG) has been developed as a new serum biomarker of disease activity in patients with IBD. However, there have been no reports on whether plasma LRG can be used as an alternative to serum LRG. Therefore, in this retrospective study, we evaluated the usefulness of plasma LRG compared to serum LRG. METHODS: We conducted a single-center retrospective observational study. A total of 108 IBD patients (ulcerative colitis [UC], 56; Crohn's disease [CD], 52) who received treatment at Sapporo Medical University Hospital between August 2020 and September 2021 were enrolled. Serum and plasma LRG levels were measured using the NANOPIA LRG kit. Disease activity was assessed using the Crohn's Disease Activity Index (CDAI) for CD and partial Mayo (pMayo) score for UC. Endoscopic activity was evaluated using the Mayo Endoscopic Subscore (MES) and Ulcerative Colitis Endoscopic Index of Severity (UCEIS) in patients with UC and the Simple Endoscopic Score for Crohn's Disease (SES-CD) score in patients with CD. RESULTS: Serum LRG levels significantly correlated with plasma LRG levels (r = 0.990, p<0.0001). Plasma LRG levels were significantly associated with SES-CD (r = 0.992, p<0.0001), indicating that plasma LRG levels may predict endoscopic activity in CD. In UC patients, the cutoff values of plasma LRG for remission were 12.7 µg/mL for MES ≤1 and 10.0 µg/mL for UCEIS of = 0. CONCLUSION: The present study showed that plasma LRG levels correlate well with serum LRG levels. Therefore, plasma LRG can be clinically applied as a biomarker for assessing endoscopic disease activity in patients with IBD.

Red blood cell distribution width as a novel marker for predicting bleeding after endoscopic resection for early gastric cancer.

Objectives: Endoscopic resection (ER) is a minimally invasive treatment for early gastric cancer (EGC); however, there is a high occurrence of bleeding. This study aimed to clarify the significance of red blood cell distribution width (RDW) as a predictive risk factor for bleeding after ER for EGC. Methods: We conducted a retrospective study based on data for patients who underwent ER for EGC from 2019 to 2021. This study included 79 lesions in 54 patients who underwent ER for EGC. The primary outcome was the association between RDW before ER and bleeding within 28 days of treatment. Receiver operating characteristic (ROC) curves were constructed, wherein areas under the curve (AUCs) and 95% confidence intervals were calculated to compare the discriminatory power of RDW for predicting bleeding. Results: Endoscopic submucosal dissection was used as the resection method for 73 lesions, whereas endoscopic mucosal resection was used for six lesions. En bloc resection was performed in all cases. There were no cases of perforation; however, bleeding after ER occurred in five cases (9.3%). ROC curve analysis of bleeding after ER showed that the AUC was 0.843 with a good diagnostic performance. When the cut-off value of RDW was set at 14.4%, sensitivity and specificity were 80% and 85.7%, respectively. There was a bleeding rate of 36.4% (4/11) at an RDW of ≥14.4%, which was significantly higher than that of 2.3% (1/43) at an RDW of <14.4%. Conclusion: RDW can be a predictor of bleeding risk after ER for EGC.

Immune-related colitis and pancreatitis treated with infliximab.

Patients with various cancers benefit from immune checkpoint inhibitors. However, immune checkpoint inhibitor-induced adverse events have also been reported, such as colitis. Prednisolone is the first-line treatment for immune-related adverse events, but second-line therapy for patients refractory to steroids has not been established. Furthermore, the inflammatory cytokine expression pattern in the intestinal mucosa of patients with steroid-refractory immune-related colitis remains unclear. We present the case of a 48-year-old man diagnosed with immune-related colitis and pancreatitis induced by pembrolizumab for advanced lung cancer. First, we administered 50 mg/day of prednisolone, and the patient's abdominal symptoms improved. However, the pancreatic enzyme levels did not return to normal. Furthermore, the patient's diarrhea worsened and hematochezia appeared at a 40 mg/day prednisolone dose. A mucosal cytokine analysis identified a low interleukin-10 messenger RNA level, which has been associated with a poor response to prednisolone. Thus, we administered 5 mg/kg of infliximab; the patient's diarrhea and hematochezia immediately improved, and the pancreatic enzyme levels returned to normal. Infliximab was administered three times every 2 weeks. After, the patient's colitis and pancreatitis did not recur. To our knowledge, this is the first report demonstrating the effectiveness of infliximab for immune-related colitis and pancreatitis.

Final Analysis of COVID-19 Patients With Inflammatory Bowel Disease in Japan (J-COSMOS): A Multicenter Registry Cohort Study.

Background and Aims: Japan has experienced 8 waves of the coronavirus disease 2019 (COVID-19) outbreak over the past 3 years, resulting in an increasing number of deaths and incidence of severe infections. This study aimed to analyze the data from the Japanese inflammatory bowel disease (IBD) patients with COVID-19 registry (J-COSMOS) up to the eighth wave to investigate the clinical course of IBD patients with COVID-19 and factors contributing to disease severity. Methods: In this multicenter, observational, cohort study, we analyzed a cohort of 1308 IBD patients diagnosed with COVID-19, enrolled across 77 participating facilities in the J-COSMOS registry from June 2020 to December 2022. Data on age, sex, IBD (classification, treatment, and activity), and COVID-19 (symptoms, severity, and treatment) were analyzed. Results: The majority of patients (76%) were in clinical remission. According to the World Health Organization classification of COVID-19 severity, 98.4% of IBD patients had nonsevere disease, while 1.6% of patients had severe or critical disease. COVID-19 did not affect disease activity in most IBD patients. Stepwise logistic regression analysis revealed that high body mass index, and cerebrovascular disease were risk factors for severe COVID-19. Corticosteroids could affect COVID-19 severity, whereas anti-tumor necrosis factor α antibodies and thiopurines were associated with a reduced risk of severe COVID-19. No deaths were observed among IBD patients with COVID-19 registered in this cohort. Conclusion: The impact of COVID-19 on IBD disease activity and factors associated with COVID-19 severity were consistent with findings of previous reports. No deaths in Japanese patients with IBD were observed.