Comparative evaluation of a language model and human specialists in the application of European guidelines for the management of inflammatory bowel diseases and malignancies.

BACKGROUND: Society guidelines on colorectal dysplasia screening, surveillance, and endoscopic management in inflammatory bowel disease (IBD) are complex, and physician adherence to them is suboptimal. We aimed to evaluate the use of ChatGPT, a large language model, in generating accurate guideline-based recommendations for colorectal dysplasia screening, surveillance, and endoscopic management in IBD in line with European Crohn's and Colitis Organization (ECCO) guidelines. METHODS: 30 clinical scenarios in the form of free text were prepared and presented to three separate sessions of ChatGPT and to eight gastroenterologists (four IBD specialists and four non-IBD gastroenterologists). Two additional IBD specialists subsequently assessed all responses provided by ChatGPT and the eight gastroenterologists, judging their accuracy according to ECCO guidelines. RESULTS: ChatGPT had a mean correct response rate of 87.8%. Among the eight gastroenterologists, the mean correct response rates were 85.8% for IBD experts and 89.2% for non-IBD experts. No statistically significant differences in accuracy were observed between ChatGPT and all gastroenterologists (P=0.95), or between ChatGPT and the IBD experts and non-IBD expert gastroenterologists, respectively (P=0.82). CONCLUSIONS: This study highlights the potential of language models in enhancing guideline adherence regarding colorectal dysplasia in IBD. Further investigation of additional resources and prospective evaluation in real-world settings are warranted.

Implementing electronic patient reported outcomes in inflammatory bowel disease: patient participation, score reliability and validity.

BACKGROUND: Patient-reported outcome measures (PROMs) are recommended for assessing patient-centered outcomes in inflammatory bowel disease (IBD). The main aims were to assess the level of participation in an electronic PROM (ePROM) data collection system among patients with IBD, and evaluate reliability and validity of the resulting scores. METHODS: Patients included in the IBD registry of Maccabi Healthcare Services, a state-mandated healthcare provider for over 2.6 million people in Israel, were invited to complete the IBD-Control measure and a general health item, with follow-up ePROMs at 3 and 6 months including a global rating of change item. Descriptive statistics were used to compare patient characteristics by participation rate, and assess survey completion time. Initial scores were assessed for internal consistency reliability using Cronbach's alpha. Test-retest reliability was assessed using the intraclass correlation coefficient from paired scores of patients identified as unchanged between the initial and first follow-up. Construct validity was assessed by the ability of IBD-control scores to discriminate between patient sub-groups in expected ways. Empirical validity was assessed using ePROM score correlations with laboratory markers of disease activity. Score coverage was also assessed. RESULTS: A total of 13,588 patients were invited to participate [Mean age = 49 years (SD = 17); females = 51%]. Participation rate was 31.5%. Participants compared to non-participants were slightly older, were more likely to be female, to have a history of biologic treatment, to have higher socio-economic status, and to be more experienced in the usage of the digital patient portal. Median survey completion time was approximately 1:30 min. Internal consistency and test-retest reliability were 0.86 and 0.98, respectively. Scores discriminated between patient sub-groups in clinically expected ways, with expected correlations to laboratory markers of disease activity. A notable ceiling effect was observed (> 15%) for IBD-Control scores. CONCLUSIONS: Feasibility, reliability, and validity of the ePROM system was supported for measuring the level of perceived disease control in patients diagnosed with IBD in Israel. Additional research is needed to identify ways to increase patient participation, assess clinical implications of the identified measurement ceiling of the IBD-control, and evaluate the added value of the derived scores in support of clinical decision making.

Trends in Biochemical Parameters, Healthcare Resource and Medication Use in the 5 Years Preceding IBD Diagnosis: A Health Maintenance Organization Cohort Study.

BACKGROUND: Few data describing pre-diagnosis changes in patients with inflammatory bowel disease (IBD) exist. We aimed to determine if there is a pattern of change in use of health resources, medications and laboratory results in the years preceding diagnosis. METHODS: This retrospective study used electronic medical records of Maccabi Health Services (MHS). Patients with IBD ≥ 16 years of age and minimum of 5-years follow-up were identified by entry into the MHS IBD registry and included in the analysis. Demographic, clinical, medication and laboratory data were collected. Generalized estimating equation model was applied to study trends and compare between years. RESULTS: This study included 5643 patients with IBD. Of these, 3039 (53.8%) had Crohn's disease (CD), 2322 (41.1%) had ulcerative colitis (UC) and 282 (5%) had indeterminate colitis (IC). Laboratory parameters including white blood cells, platelets and C-reactive protein showed significant increases while haemoglobin and mean cell volume showed significant decreases in mean values in the 2 years prior to diagnosis with stable values prior to that (p < 0.0001). Parameters such as creatinine, total protein and albumin showed significant, progressive decreases in mean values starting 5 years prior to diagnosis (p < 0.0001). Patients with CD had distinct laboratory trends when compared with patients with UC. CONCLUSIONS: Changes in laboratory parameters, healthcare service and medication use occur during the 5-year period before IBD diagnosis. These data can have future clinical applicability by developing a composite score and referral algorithm introducing red flags into primary care visits and appropriate referral for specialist care.

COVID-19 in Patients with Inflammatory Bowel Disease: The Israeli Experience.

BACKGROUND: Crohn's disease (CD) and ulcerative colitis (UC) are chronic, immune-mediated inflammatory bowel diseases (IBD) affecting millions of people worldwide. IBD therapies, designed for continuous immune suppression, often render patients more susceptible to infections. The effect of the immune suppression on the risk of coronavirus disease-19 (COVID-19) is not fully determined yet. OBJECTIVE: To describe COVID-19 characteristics and outcomes and to evaluate the association between IBD phenotypes, infection outcomes and immunomodulatory therapies. METHODS: In this multi-center study, we prospectively followed IBD patients with proven COVID-19. De-identified data from medical charts were collected including age, gender, IBD type, IBD clinical activity, IBD treatments, comorbidities, symptoms and outcomes of COVID-19. A multivariable regression model was used to examine the effect of immunosuppressant drugs on the risk of infection by COVID-19 and the outcomes. RESULTS: Of 144 IBD patients, 104 (72%) were CD and 40 (28%) were UC. Mean age was 32.2 ± 12.6 years. No mortalities were reported. In total, 94 patients (65.3%) received biologic therapy. Of them, 51 (54%) at escalated doses, 10 (11%) in combination with immunomodulators and 9 (10%) with concomitant corticosteroids. Disease location, behavior and activity did not correlate with the severity of COVID-19. Biologics as monotherapy or with immunomodulators or corticosteroids were not associated with more severe infection. On the contrary, patients receiving biologics had significantly milder infection course (p = 0.001) and were less likely to be hospitalized (p = 0.001). Treatment was postponed in 34.7% of patients until recovery from COVID-19, without consequent exacerbation. CONCLUSION: We did not witness aggravated COVID-19 outcomes in patients with IBD. Patients treated with biologics had a favorable outcome.

Intermittent Appearance of Antibodies to Infliximab Is Not Associated With Reduced Efficacy in Patients With Inflammatory Bowel Diseases.

GOALS: To assess the clinical significance of antibodies to infliximab (ATI) formation in patients with inflammatory bowel disease (IBD). BACKGROUND: Infliximab therapy in patients with IBD is highly effective though up to 50% of patients lose response to infliximab. ATI formation occurs in 6% to 60% of patients on scheduled infliximab maintenance therapy. METHODS: Infliximab trough levels and ATI at trough were prospectively determined in patients with IBD on maintenance infliximab therapy. Patients on infliximab maintenance therapy with at least 3 ATI measurements were included. Patients were divided into 2 groups: sustained negative (<1 µg/mL) ATI levels, and fluctuating ATI levels (at least 1 sample with ATI <1 and at least one >1 µg/mL). RESULTS: Forty-eight patients with IBD with available clinical data and serum samples were included. 25 patients had sustained low ATI levels and 23 patients had fluctuating ATI levels. Both groups were similar in IBD subtype distribution (Crohn's disease in 73.9% and 60%), mean serum albumin levels (4.2 vs. 3.9 g/dL), and mean trough serum infliximab levels (3.3 vs. 4.6 µg/mL) in fluctuating ATI and low ATI groups, respectively. There were no significant differences in the rate of clinical response (64% vs. 76%) and mean serum C-reactive protein levels (9.4 vs. 8.5 mg/dL, ULN=5) in the fluctuating ATI and low ATI groups. Similar rates of clinical response in the fluctuating ATI and low ATI groups were observed in ulcerative colitis (33% vs. 40%) and Crohn's disease (76% vs. 100%). CONCLUSIONS: The fluctuating pattern of appearance of ATI in patients with IBD was not associated with loss of clinical response or a rise in C-reactive protein. The authors suggest that in clinical decision making, only sustained appearance of ATI should be considered as an adverse therapeutic factor.

Risk of Cancer in Paediatric onset Inflammatory Bowel Diseases: A Nation-wide Study From the epi-IIRN.

BACKGROUND: Paediatric onset IBD [PIBD] is characterised by a more extensive phenotype than adult-onset IBD and a higher utilisation of immunosuppressive medications; both may be associated with malignancy. We aimed to assess the risk of cancer in a nationwide cohort of PIBD and to explore the risks associated with medical treatments. METHODS: PIBD patients [<18 years old] were included from the epi-IIRN cohort, covering 98% of the Israeli population from 2005, linked to the national cancer registry. We matched PIBD children to non-IBD children for calculating the cumulative incidence of cancer. RESULTS: In all, 3944 PIBD cases were included (2642 [67%] Crohn's disease, 1302 [33%] ulcerative colitis) translating into 23 635 person-years of follow-up, individually matched to 13 005 non-IBD children. By 30 years of age, 14 IBD patients [0.35%, 5.9/10 000 patient-years] were diagnosed with cancer and one [0.03%] with haemophagocytic-lymphohistiocytosis [HLH], compared with 14 [0.11%, 1.9/10 000 patient-years] cases of cancer {relative risk (RR) 2.5 (95% confidence interval [CI] 1.05-6.2); p = 0.04} and no HLH in the comparison-group. There were no cases of hepatosplenic T cell lymphoma, adenocarcinoma, or cholangiocarcinoma. Cancer risk was 15.6 cases/10 000 person-years in those treated with thiopurines alone (RR compared with IBD patients never exposed to either thiopurines or anti-tumuor necrosis factor [TNF] 1.8 [95% CI 0.6-6.1]; p = 0.2), 11.1/10 000 in those treated with anti-TNF alone (RR 1.3 [95% CI 0.3-6.6]; p = 0.5), and 23.1/10 000 treated with combination therapy of anti-TNF and thiopurines (RR 2.8 [95% CI 0.6-13.8]; p = 0.2). CONCLUSIONS: PIBD confers an increased risk for malignancy compared with non-IBD in children. However, the absolute risk is very low and no differences in risk with specific therapies were apparent in our data.

Differential Serum-intestinal Dynamics of Infliximab and Adalimumab in Inflammatory Bowel Disease Patients.

BACKGROUND AND AIMS: Therapeutic drug monitoring is used to guide anti-tumour necrosis factor [TNF] therapy. However, the associations between serum drug levels [SDL], TNF-bound, and free anti-TNF in the target tissue are incompletely defined. We aimed to assess the interactions between these parameters in inflammatory bowel disease [IBD] patients. METHODS: ENZYME-LINKED IMMUNOSORBENT: assays [ELISA assays] were used to detect free drug and TNF-drug complexes in intestinal tissues. Concurrent SDL, anti-drug antibodies [ADA], pharmacotherapy, clinical response, endoscopic appearance, and histological severity were determined. Comparisons between anti-TNFs and paired inflamed/non-inflamed tissue were performed. Variables were correlated and potential interactions detected using multivariate analysis. RESULTS: A total of 95 biopsies taken from 49 anti-TNF treated IBD patients [26 receiving infliximab and 23 adalimumab] were studied. Free drug levels were higher in inflamed compared with non-inflamed paired specimens. Tissue free-drug and TNF-drug complexes levels were higher in adalimumab-treated patients. In adalimumab-treated patients, SDL were correlated with free drug, but not TNF-drug complex levels, in both inflamed and non-inflamed segments. In infliximab-treated patients, higher SDL were associated with the presence of tissue free drug in both inflamed and non-inflamed segments, whereas TNF-drug complexes were mostly detected in non-inflamed but not in inflamed tissue. In the presence of ADA, neither free drug nor TNF-infliximab complexes were measured in the tissue. Tissue levels did not correlate well with clinical, endoscopic, or histological scores. CONCLUSIONS: SDL correlated with tissue free drug levels; however, different dynamics were observed for TNF-drug complex levels. Infliximab and adalimumab tissue drug dynamics differ. Better understanding of these interactions may allow future therapeutic optimisation.

Early Indolent Course of Crohn's Disease in Newly Diagnosed Patients Is Not Rare and Possibly Predictable.

BACKGROUND & AIMS: The early stages of Crohn's disease (CD) course are heterogeneous, and it is a challenge to predict the course of disease in patients with new diagnosis. METHODS: We performed an observational longitudinal study of 156 adults (79 male; median age, 27.7 years; 57 treatment naïve) with newly diagnosed CD (within 6 months of enrollment), referred from medical centers and community clinics in Israel from 2013 through 2017. Study participants each received semi-annual scheduled evaluations. Indolent disease was defined as a disease course without need for strict interventions to control complicated course of CD (hospitalization or surgery, or decision to start steroid, immunomodulator, or biologic therapy). Cox regression and receiver operating characteristic analyses were used to identify factors associated with early indolent or complicated course of CD. We validated our findings in an independent cohort of patients with CD from a separate medical center in Israel in 2018. RESULTS: Over a median follow-up period of 17.2 months (interquartile range, 8.8-23.8 months), 52 patients (33.3%) had an indolent course of CD, 29 (18.5%) required hospitalizations, and 75 (48%) were recommended to start steroid, immunomodulator, or biologic therapies. The median time to first intervention was 3.4 months (95% CI, 2.4-4.4). We developed a model based on clinical factors that identified 4 factors associated with complicated course in treatment-naïve patients: body mass index <25 kg/m2 (hazard ratio [HR], 2.45; 95% CI, 1.07-5.43; P = .033), serum level of vitamin B12 <350 pg/mL (HR, 2.78; 95% CI, 1.21-6.41; P = .016), white blood cells ≥7 × 103/µL (HR, 2.419; 95% CI, 1.026-5.703; P = .044), and serum level of ALT ≥25 IU/L (HR, 2.680; 95% CI, 1.186-6.058; P = .018). This model discriminated between patients with vs without a complicated course of disease with 90% and 89% accuracy at 6 and 12 months after diagnosis, respectively. A validation cohort demonstrated a discriminatory ability of 79% at 3 months after diagnosis, and a nomogram was constructed. CONCLUSIONS: In an observational longitudinal study of 156 patients with newly diagnosed CD, we found that one third have an early indolent course of disease. We identified factors that can be measured at diagnosis to identify patients at risk for an early complicated course-these might be used in patient management and selection of treatment.

Physician adherence to societal guidelines following colonoscopy with polypectomy.

BACKGROUND: Colorectal cancer is a significant cause of mortality and morbidity in western countries. Polypectomy reduces the incidence and mortality of colorectal cancer. Following polypectomy, recommendations regarding the frequency and duration of surveillance rely mostly on features of the resected polyps and are summarized in various gastroenterological societal guidelines. In this study, we aimed to delineate the accuracy of current post-polypectomy surveillance recommendations and to check whether active intervention would lead to an improvement in accuracy and consistency with societal guidelines. METHODS: We prospectively collected polypectomy reports over a 3-month period in 2 tertiary medical centers. We then performed an intervention that included: 1) presentation of results from 1st phase; 2) re-affirming the guidelines in a departmental meeting; 3) addition of a dedicated reporting form for post-polypectomy surveillance recommendations in the patients' electronic medical file. Finally, we conducted a second prospective collection of post-polypectomy recommendations, over a second 3-month period. RESULTS: Prior to the intervention, 76% of the colonoscopies with polypectomy had a recommendation for surveillance, compared to 85% after the intervention (P=0.003). Prior to the intervention, 65% of patients received a recommendation consistent with societal guidelines, compared with 78% after the intervention (P=0.001). CONCLUSION: Intervention, including re-affirmation of the current guidelines and creation of a dedicated reporting platform, significantly increases the number of follow-up recommendations after polypectomy and their consistency with societal guidelines.

Safety and effectiveness of ustekinumab for induction of remission in patients with Crohn's disease: A multicenter Israeli study.

INTRODUCTION: Ustekinumab is an effective treatment of Crohn's disease (CD). Real-world data addressing the efficacy and safety of ustekinumab are scarce. AIM: Our aim was to assess the safety and efficacy of ustekinumab in a large national patient cohort. METHODS: A prospective multicenter study, in which we followed patients with active CD treated with ustekinumab for 24 weeks. Induction dose was intravenous ranging from 260 to 520 mg, according to body weight, followed by 90 mg doses given subcutaneously every 8 weeks. Clinical response was defined as a reduction of at least 1 severity category, as defined by Harvey-Bradshaw index (HBI). Patients with HBI < 5 were considered to be in clinical remission. Patients who stopped needing steroids at week 24 were defined as being in steroid-free clinical remission. RESULTS: A total of 106 CD patients from eight Israeli centers were included. All patients were previously exposed to at least one biological agent. Our cohort consisted of 65 (61.3%) females. Mean age was 41 ± 14 years with an average disease duration of 12.2 ± 8 years. A total of 96 (90.5%) patients continued treatment throughout week 24. Clinical response was observed in 52% of these patients with mean HBI reduction from 8.34 ± 3.8 to 6.8 ± 4.4 at week 24 (p = 0.001). Clinical remission was achieved in 33 patients (31.1%). Moreover, the number of patients requiring steroid treatment was reduced by 66% at week 24. Out of 106 patients, 11 patients (10.4%) discontinued treatment: 3 due to adverse events (2.8%), 7 due to a lack of response, and 1 who was lost to follow-up. Following 24 weeks of treatment, 15 patients reported minor adverse events. CONCLUSIONS: In a large real-world Israeli cohort of non-naïve-to-biological-treatment CD patients, ustekinumab was effective and safe in induction of clinical remission with a significant reduction in the number of patients requiring steroid treatment.

Does early corticosteroid therapy affect prognosis in IBD patients hospitalized with Clostridioides difficile infection?

BACKGROUND: Corticosteroids (CS) therapy to Clostridioides difficile infection (CDI) in inflammatory bowel disease (IBD) flares may worsen CDI outcomes. AIM: Assess the impact of early CS exposure on outcomes of IBD patients diagnosed with CDI. METHODS: Retrospective study of IBD patients admitted with first-time CDI between 2002 and 2018. Comparisons were made based on CS exposure 48 h from admission. Patients were further subdivided to 5 groups based on CS-antibiotics temporal exposure. The primary outcome was all-cause mortality or colectomy within 3 months. Secondary outcomes were colectomy and mortality rates at 1 year, length of stay, readmissions, bacteremia, and diarrhea improvement by day 7/discharge. Cox proportional hazard model and Kaplan-Meier curves were used to assess the effects on survival. Logistic and ordinal regressions were used to assess primary and secondary outcomes. RESULTS: One hundred thirteen patients (64 CD, 46 UC, and 3 IBDU) were included, 82 (72.5%) received early CS. At baseline, CRP was significantly lower and albumin was higher in the group not exposed to early CS. At 3 months, 4 (4.8%) patients required colectomy and 6 (5.8%) died (p = NS). Length of stay was significantly reduced among patients not exposed to early CS. All other endpoints were not associated with CS exposure. In subgroup analysis, the primary outcome was not significantly different among the sub-groups. Mortality rate at 1 year was significantly lower in patients who did not receive antibiotics for CDI. CONCLUSION: Early CS therapy in IBD patients hospitalized with CDI is not associated with worse clinical outcomes. However, additional prospective research is required.

Cell-centred meta-analysis reveals baseline predictors of anti-TNFα non-response in biopsy and blood of patients with IBD.

OBJECTIVE: Although anti-tumour necrosis factor alpha (anti-TNFα) therapies represent a major breakthrough in IBD therapy, their cost-benefit ratio is hampered by an overall 30% non-response rate, adverse side effects and high costs. Thus, finding predictive biomarkers of non-response prior to commencing anti-TNFα therapy is of high value. DESIGN: We analysed publicly available whole-genome expression profiles of colon biopsies obtained from multiple cohorts of patients with IBD using a combined computational deconvolution-meta-analysis paradigm which allows to estimate immune cell contribution to the measured expression and capture differential regulatory programmes otherwise masked due to variation in cellular composition. Insights from this in silico approach were experimentally validated in biopsies and blood samples of three independent test cohorts. RESULTS: We found the proportion of plasma cells as a robust pretreatment biomarker of non-response to therapy, which we validated in two independent cohorts of immune-stained colon biopsies, where a plasma cellular score from inflamed biopsies was predictive of non-response with an area under the curve (AUC) of 82%. Meta-analysis of the cell proportion-adjusted gene expression data suggested that an increase in inflammatory macrophages in anti-TNFα non-responding individuals is associated with the upregulation of the triggering receptor expressed on myeloid cells 1 (TREM-1) and chemokine receptor type 2 (CCR2)-chemokine ligand 7 (CCL7) -axes. Blood gene expression analysis of an independent cohort, identified TREM-1 downregulation in non-responders at baseline, which was predictive of response with an AUC of 94%. CONCLUSIONS: Our study proposes two clinically feasible assays, one in biopsy and one in blood, for predicting non-response to anti-TNFα therapy prior to initiation of treatment. Moreover, it suggests that mechanism-driven novel drugs for non-responders should be developed.

Effectiveness and safety of vedolizumab for maintenance treatment in inflammatory bowel disease-The Israeli real world experience.

INTRODUCTION: Several real-world experience (RWE) studies with vedolizumab (VDZ) for induction of remission in inflammatory bowel diseases (IBD) have been published; however, long-term RWE data is scarce. AIMS: To describe the effectiveness and safety of VDZ in maintenance treatment of IBD. METHODS: A multicenter retrospective national study. The primary outcome of was clinical response at week 52; main secondary aims included clinical remission at week 52, rates of secondary loss of response and treatment discontinuation. RESULTS: We included 193 (133-CD; 60-UC) patients from 9 Israeli IBD centers. At week 52, response was observed in 62/133 (46.7%) CD patients, including 28 (21%) in clinical remission; 71 (53.3%) discontinued treatment or did not respond. For UC, response at week 52 was observed in 27/60 (45%), including 20 (33%) in clinical remission; 33 (55%) discontinued treatment or did not respond. Secondary non-response by week 52 occurred in 19.4% and 23.5% of week 14 responders in CD and UC, respectively. Week 14 response was associated with treatment continuation at week 52: no predictors of secondary loss of response were identified. SUMMARY: VDZ is safe and effective for maintenance of response and remission in IBD; week 14 response is positively associated with long-term response in both UC and CD.

Association of Vedolizumab Level, Anti-Drug Antibodies, and α4ß7 Occupancy With Response in Patients With Inflammatory Bowel Diseases.

BACKGROUND & AIMS: There are few data available on the real-life pharmacokinetic and pharmacodynamics features of vedolizumab, a monoclonal antibody against integrin α4ß7. We performed a prospective study of patients with inflammatory bowel diseases (IBDs) treated with vedolizumab to determine serum drug concentrations, formation of antivedolizumab antibodies (AVAs), and integrin α4ß7 saturation. METHODS: We performed a prospective study of 106 patients with IBD (67 with Crohn's disease and 39 with ulcerative colitis) treated with vedolizumab from September 2014 through March 2017 at 2 tertiary medical centers in Israel. Clinical data and serum samples were collected before and during induction and maintenance therapy. Clinical remission was defined as Harvey-Bradshaw index scores below 5 or as Simple Clinical Colitis Activity Index scores of 3 or less. We measured serum levels of vedolizumab, AVAs, and markers of inflammation. Peripheral blood mononuclear cells were obtained from some patients at designated trough time points and CD3+ CD45RO+ T cells were isolated from 36 samples. Cells were incubated with fluorescent-conjugated vedolizumab and flow cytometry was used to quantify α4ß7 integrin saturation. We also performed flow cytometry analyses of CD3+ CD45RO+ lamina propria T cells isolated from intestinal mucosa of patients without IBD (non-IBD controls, n = 6), patients with IBD not treated with vedolizumab (untreated IBD controls, n = 8), and patients with IBD treated with vedolizumab (n = 15). RESULTS: Clinical remission was achieved by 48 of 106 patients (45%) by week 6 and 50 of 106 patients (48%) by week 14 of treatment. The median level of vedolizumab at week 6 was higher in patients in clinical remission (40.2 µg/mL) than in patients with active disease (29.7 µg/mL; P = .05). The median serum level of vedolizumab was significantly higher in patients with a normal level of C-reactive protein (21.8 µg/mL vedolizumab) vs the level in those with a high level of C-reactive protein (11.9 µg/mL vedolizumab) during maintenance treatment (P = .0006). The other clinical outcomes measured were not associated with median serum level of vedolizumab at any time point examined. AVAs were detected in 17% of patients during induction therapy and 3% of patients during maintenance therapy, but did not correlate with clinical outcomes. Flow-cytometry analysis of peripheral blood memory T cells (n = 36) showed near-complete occupancy of α4ß7 integrin at weeks 2 and 14 and during the maintenance phase, regardless of response status or drug levels. Most intestinal CD3+CD45RO+ memory T cells of healthy and IBD controls expressed α4ß7 (72%; interquartile range, 56%-81%). In contrast, free α4ß7 was detectable on only 5.6% of intestinal memory cells (interquartile range, 4.4%-11.2%) (P < .0001) from vedolizumab-treated patients, regardless of response. CONCLUSIONS: In a prospective study of real-life patients with IBD, we associated vedolizumab drug levels with remission and inflammatory marker level. Integrin α4ß7 was blocked in almost all T cells from patients treated with vedolizumab, regardless of serum level of the drug or response to treatment. These findings indicate a need to explore alternative mechanisms that prevent response to vedolizumab.

Impact of Infliximab and Cyclosporine on the Risk of Colectomy in Hospitalized Patients with Ulcerative Colitis Complicated by Cytomegalovirus-A Multicenter Retrospective Study.

BACKGROUND: Cytomegalovirus (CMV) is frequently detected in patients with ulcerative colitis (UC). The impact of CMV infection on the outcome of UC exacerbation remains unclear. The benefit of combining antiviral with anti-inflammatory treatment has not been evaluated yet. The aim of this study was to compare the outcome of CMV-positive hospitalized patients with UC treated with antiviral therapy either alone or combined with salvage anti-inflammatory therapy (infliximab [IFX] or cyclosporine A [CsA]). METHODS: This was a multicenter retrospective study of hospitalized CMV-positive patients with UC. The patients were classified into 2 groups: antiviral-if treated with antivirals alone; combined-if treated with both antiviral and anti-inflammatory therapy. The outcomes included the rate of colectomy in both arms during the course of hospitalization and after 3/12 months. RESULTS: A total of 110 patients were included; 47 (42.7%) patients did not receive IFX nor CsA; 36 (32.7%) received IFX during hospitalization or within 1 month before hospitalization; 20 (18.1%) patients received CsA during hospitalization; 7 (6.4%) were exposed to both IFX and CsA. The rate of colectomy was 14.5% at 30 days, 20.0% at 3 months, and 34.8% at 12 months. Colectomy rates were similar across treatment groups. No clinical and demographic variables were independently associated with the risk of colectomy. CONCLUSIONS: IFX or cyclosporine therapy is not associated with additional risk for colectomy over antiviral therapy alone in hospitalized CMV-positive patients with UC.

Efficacy and Safety of Vedolizumab for Induction of Remission in Inflammatory Bowel Disease-the Israeli Real-World Experience.

BACKGROUND: Vedolizumab (VDZ) is an anti-integrin monoclonal antibody effective in ulcerative colitis (UC) and Crohn's disease (CD). The aim of this study was to examine the "real world" efficacy and safety of VDZ in a large national patient cohort. METHODS: Patients with inflammatory bowel disease treated with VDZ were prospectively followed for 14 weeks. Patients who completed the induction protocol (week 0/2/6/14) or discontinued the treatment before week 14 for adverse events (AEs) or primary nonresponse were included. The primary outcome was induction of clinical remission at week 14; secondary outcomes included clinical response and corticosteroid-free clinical remission. RESULTS: A total of 204 patients (CD-130, UC-69, inflammatory bowel disease-unclassified-5) from 8 centers in Israel were included. Fifteen (7.4%) of the patients were anti-tumor necrosis factor naive and 46 (35.4%) had a previous surgery. For patients with CD, 69/130 (53.1%) responded to treatment; 45 (34.6%) achieved clinical remission; and 38 (29.2%) achieved corticosteroid-free remission at week 14. Fourteen (10.7%) patients discontinued VDZ before week 14 due to primary nonresponse or AEs. For UC, 32/74 (43.2%) responded to treatment; 20 (28.4%) achieved clinical remission, and 18 (24.3%) achieved corticosteroid-free remission at week 14. Fifteen (20.3%) patients with UC did not complete the induction due to primary nonresponse or AEs. AEs were reported by 29 (14.2%) patients (CD and UC combined), most common being nasopharyngitis and skin eruptions. CONCLUSIONS: In a large real-world Israeli cohort of anti-tumor necrosis factor-experienced patients with inflammatory bowel disease, VDZ was effective and safe in induction of clinical remission and steroid-free clinical remission.

Prevention of Antidrug Antibody Formation to Infliximab in Crohn's Patients With Prior Failure of Thiopurines.

BACKGROUND & AIMS: Combination thiopurine-infliximab (IFX) therapy is associated with reduced generation of antidrug antibodies (ADA) compared with IFX monotherapy. Whether past clinical response to thiopurine therapy bears an effect on ADA prevention is unknown. METHODS: This was a retrospective observational multicenter study of patients with Crohn's disease (CD) treated by IFX and thiopurines who had serial ADA measurements. Therapy was classified into past thiopurine response or its lack of, de novo combination, or IFX monotherapy. The primary endpoint was risk of ADA appearance. RESULTS: Out of 494 patients with serial ADA measurements 207 eligible patients were included in the final analysis. The 1-year cumulative risk of ADA development was similar in past thiopurine responders (19.3%) compared with past thiopurine failures (16.1%) (log rank P = .54). ADA was found in 46.6% of the monotherapy group and was significantly different compared with past thiopurine responders (P = .007) and past thiopurine failures (P = .007). The adjusted hazards for ADA development were significantly lower in past responders and past failures compared with the monotherapy group (hazard ratio, 0.47 [95% CI, 0.22-1.00] and 0.32 [95% CI, 0.11-0.93], respectively). CONCLUSIONS: Thiopurines-IFX cotherapy in patients with Crohn's disease is associated with reduced ADA formation compared with IFX monotherapy. This is probably regardless of initial thiopurine therapeutic effect.

The association of the MTHFR C677T polymorphism with inflammatory bowel diseases in the Israeli Jewish population: An example of genetic heterogeneity.

MTHFR C677T is a common gene polymorphism that has been shown to be associated with hyperhomocysteinemia. Studies on the role of MTHFR in inflammatory bowel diseases (IBD) have yielded conflicting results, perhaps due in part to genetic heterogeneity. The prevalence of the MTHFR C677T variant allele varies according to Jewish subpopulations: Ashkenazi vs non-Ashkenazi. The aim of this study was to examine the association between MTHFR C677T genotype and IBD in the different Jewish populations.DNA samples were assessed for the presence of the MTHFR C677T variant allele in 445 Jewish Israeli IBD patients: 338 with Crohn's disease [CD] (214 Ashkenazi and 124 non-Ashkenazi Jews) and 107 with ulcerative colitis [UC] (73 Ashkenazi and 34 non-Ashkenazi Jews), and in 347 healthy controls: 173 Ashkenazi and 174 Non-Ashkenazi Jews. Possible genotype-phenotype associations were investigated.We showed a significantly higher frequency of MTHFR 677T variant genotypes in non-Ashkenazi CD patients: Odds ratio of 1.86 for heterozygotes (CT) and 2.89 for homozygotes (TT) compared to non-Ashkenazi healthy controls. No significant association was found for UC in non-Ashkenazi patients or for CD or UC in Ashkenazi patients.Our findings suggest that the MTHFR 677T variant may contribute to the risk of CD in non-Ashkenazi but not Ashkenazi Jews. This may result from genetic heterogeneity and highlights the complexity of the genetic etiology of IBD.

Genetic Predictors of Benign Course of Ulcerative Colitis-A North American Inflammatory Bowel Disease Genetics Consortium Study.

BACKGROUND: A subset of patients with ulcerative colitis (UC) have a benign course and an overall favorable prognosis. Early identification of these low-risk patients may allow for a less aggressive therapeutic approach and possible reduction of therapy-associated risks. The aim of this project was to identify the genetic predictors of benign UC phenotype. METHODS: UC patients were selected from the National Institute of Diabetes and Digestive and Kidney Diseases Inflammatory Bowel Disease Genetics Consortium. Benign phenotype was defined as no need for immunomodulatory or biological therapy, hospitalizations, or colectomy. The association between benign UC phenotype and known loci linked to the risk of inflammatory bowel disease (IBD) was evaluated. The results for 156 index single-nucleotide polymorphisms (SNPs) from the known IBD loci were extracted for the main analysis. The association of the benign phenotype to a genetic burden score was also evaluated. RESULTS: None of the index SNPs from the IBD loci reached the predefined threshold of 1 × 10. In the exploratory analysis of the remaining Immunochip SNPs and imputed major histocompatibility complex data, 5 distinct suggestive association signals are identified (rs1697950, rs2523639, rs17836409, rs11742854, and rs75001121). CONCLUSIONS: No SNPs from IBD susceptibility loci were found to be associated (at our predefined threshold of 1 × 10) with a benign UC disease course. The rs11742570 variant on chromosome 5 was the one with the greatest association to benign disease although the association did not reach the predefined significant threshold. Given the modest power of our study, the findings suggested on the exploratory analysis merit extension to larger discovery cohorts.