Exclusive Enteral Nutrition Mediates Beneficial Gut Microbiome Enrichment in Acute Severe Colitis.

BACKGROUND: Exclusive enteral nutrition (EEN) supplementation of the standard of care (SOC) augments steroid responsiveness in patients with acute severe ulcerative colitis (ASUC). EEN is known to alter gut microbial composition. The present study investigates EEN-driven gut microbial alterations in patients with ASUC and examines their correlations with clinical parameters. METHODS: Stool samples from patients with ASUC (n = 44) who received either EEN-supplemented SOC (EEN group; n = 20) or SOC alone (SOC group; n = 24) for 7 days were collected at baseline (day 0) and postintervention (day 7). Microbiome analysis was carried out using 16S ribosomal RNA gene sequencing followed by data processing using QIIME2 and R packages. RESULTS: Seven-day EEN-conjugated corticosteroid therapy in patients with ASUC enhanced the abundances of beneficial bacterial genera Faecalibacterium and Veillonella and reduced the abundance of Sphingomonas (generalized linear model fitted with Lasso regularization with robustness of 100%), while no such improvements in gut microbiota were observed in the SOC group. The EEN-associated taxa correlated with the patient's clinical parameters (serum albumin and C-reactive protein levels). Unlike the SOC group, which retained its preintervention core microbiota, EEN contributed Faecalibacterium prausnitzii, a beneficial gut bacterial taxon, to the gut microbial core. EEN responders showed enhancement of Ligilactobacillus and Veillonella and reduction in Prevotella and Granulicatella. Analysis of baseline gut microbiota showed relative enhancement of certain microbial genera being associated with corticosteroid response and baseline clinical parameters and that this signature could conceivably be used as a predictive tool. CONCLUSIONS: Augmentation of clinical response by EEN-conjugated corticosteroid therapy is accompanied by beneficial gut microbial changes in patients with ASUC.

Exclusive enteral nutrition­supplemented corticosteroid therapy in acute severe ulcerative colitis (ASUC) is accompanied by the enrichment of beneficial gut microbial genera, which correlate negatively with the disease activity scores and objective inflammatory markers in ASUC. The baseline gut microbiota in ASUC associates with and may predict corticosteroid response.

Inflammatory bowel disease (IBD) in rural and urban India: results from community colonoscopic evaluation of more than 30,000 symptomatic patients.

Background: Traditionally, infectious diarrhoea has been the major cause of lower GI symptoms across the developing world. Increasing urbanization has been implicated for the rising IBD cases despite very limited data in the rural setting. We aimed to assess the relative proportion of IBD and other intestinal diseases among symptomatic patients from rural and urban India. Methods: Patients with lower GI symptoms attending urban out-patient clinics and/or specially conducted mobile rural health camps were evaluated using basic laboratory parameters, abdominal ultrasound and colonoscopy. Data including patient demographics, symptom profile, rural/urban residence and final diagnosis were analyzed. Current data was compared with previous rural survey in 2006. Findings: Of 32,021 patients investigated, 30,835 with complete dataset [67% male; 21% (6362) rural median 44 years:6-78 years] were included. Predominant symptoms were chronic abdominal pain (55%), change in bowel habit (45%), rectal bleeding (16%), chronic diarrhoea (13%), un-intended weight loss (9%) and anaemia (3%). Final diagnoses included IBD: (1687; 5.4%; 2.2% ulcerative colitis (UC), 3.2% Crohn's disease, CD), intestinal tuberculosis (364; 1.2%), infective colitis (1427; 4.6%), colorectal cancer (488; 1.6%) and polyps (2372; 7.7%). Proportions of UC (2.1% rural, 2.3% urban, p = 0.66) and CD (3.5% rural, 3.1%,urban, p = 0.12) were similar in both groups. There was no rural-urban divide in the relative proportion of other intestinal diseases. Interpretation: IBD accounts for more than 5% of patients presenting with lower GI symptoms, a rate that is higher than that of infectious colitis. The proportion of IBD cases was not different between the rural and urban populations. These data appear to indicate the changing disease prevalence patterns in India that require further research. Funding: The study was funded by Leona M. and Harry B. Helmsley Charitable Trust.

Efficacy of oral prolonged-release mesalazine in moderately active ulcerative colitis.

New meta-analyses are presented that provide further evidence supporting the effectiveness of oral prolonged-release mesalazine compared to other oral mesalazines as induction therapy in patients with moderately active ulcerative colitis.

Development of the Escalation of Therapy or Intervention (ETI) Calculator for Patients with Ulcerative Colitis Using ePROMs.

BACKGROUND AND AIMS: Digital collection of patient-reported outcome measures [PROMs] is largely unexplored as a basis for follow-up for patients with ulcerative colitis [UC]. Our aim was to develop a model to predict the likelihood of escalation of therapy or intervention at an outpatient appointment that may be used to rationalize follow-up. METHODS: TrueColours-IBD is a web-based, real-time, remote monitoring software that allows longitudinal collection of ePROMs. Data for prediction modelling were derived from a Development Cohort, guided by the TRIPOD statement. Logistic regression modelling used ten candidate items to predict escalation of therapy or intervention. An Escalation of Therapy or Intervention [ETI] calculator was developed, and applied in a Validation Cohort at the same centre. RESULTS: The Development Cohort [n = 66] was recruited in 2016 and followed for 6 months [208 appointments]. From ten items, four significant predictors of ETI were identified: SCCAI, IBD Control-8, faecal calprotectin, and platelets. For practicality, a model with only SCCAI and IBD Control-8, both entered remotely by the patient, without the need for faecal calprotectin or blood tests was selected. Between 2018 and 2020, a Validation Cohort of 538 patients [1188 appointments] was examined. A 5% threshold on the ETI calculator correctly identified 343/388 [88%] escalations and 274/484 [57%] non-escalations. CONCLUSIONS: A calculator based on digital, patient-entered data on symptoms and quality of life can predict whether a patient with UC requires escalation of therapy or intervention at an outpatient appointment. This may be used to streamline outpatient appointments for patients with UC.

Clinical Effect of Mirikizumab Treatment on Bowel Urgency in Patients with Moderately to Severely Active Ulcerative Colitis and the Clinical Relevance of Bowel Urgency Improvement for Disease Remission.

Background: Bowel urgency reduces ulcerative colitis patients' quality of life. Mirikizumab, a p19-directed anti-IL-23 antibody, demonstrates ulcerative colitis efficacy. Mirikizumab efficacy to reduce bowel urgency and bowel urgency association with other endpoints were analyzed in 2 Phase 3 trials. Methods: LUCENT-1 (Induction): 1162 patients randomized 3:1 to intravenous 300 mg mirikizumab or placebo every 4 weeks for 12 weeks. LUCENT-2 (Maintenance): 544 mirikizumab responders during induction were re-randomized 2:1 to subcutaneous mirikizumab 200 mg or placebo every 4 weeks for 40 weeks (52 weeks of continuous treatment). Bowel urgency was measured using the Urgency Numeric Rating Scale (0-10); for patients with LUCENT-1 baseline score ≥3, bowel urgency clinically meaningful improvement (≥3-point decrease) and remission (score ≤1) rates in mirikizumab versus placebo groups were compared at Weeks 12 and 52. Associations between bowel urgency and other efficacy endpoints were assessed at Weeks 12 and 52. Results: A significantly higher proportion of mirikizumab patients versus placebo achieved clinically meaningful improvement in bowel urgency and remission at Weeks 12 and 52. Significantly higher percentages of patients achieving bowel urgency clinically meaningful improvement or remission, compared with those who did not, also achieved endpoints for clinical, corticosteroid-free, endoscopic, and symptomatic remission; clinical response; normalized fecal calprotectin and C-reactive protein; and improved quality of life. Conclusions: In patients with ulcerative colitis, bowel urgency improvement was associated with better clinical outcomes than in patients without improvement during induction and maintenance. A greater proportion of mirikizumab patients achieved sustainable bowel urgency improvement and remission compared to placebo patients.

Early management of acute severe UC in the biologics era: development and international validation of a prognostic clinical index to predict steroid response.

OBJECTIVES: We aimed to determine whether changes in acute severe colitis (ASC) management have translated to improved outcomes and to develop a simple model predicting steroid non-response on admission. DESIGN: Outcomes of 131 adult ASC admissions (117 patients) in Oxford, UK between 2015 and 2019 were compared with data from 1992 to 1993. All patients received standard treatment with intravenous corticosteroids and endoscopic disease activity scoring (Ulcerative Colitis Endoscopic Index of Severity (UCEIS)). Steroid non-response was defined as receiving medical rescue therapy or surgery. A predictive model developed in the Oxford cohort was validated in Australia and India (Gold Coast University Hospital 2015-2020, n=110; All India Institute of Medical Sciences, New Delhi 2018-2020, n=62). RESULTS: In the 2015-2019 Oxford cohort, 15% required colectomy during admission vs 29% in 1992-1993 (p=0.033), while 71 (54%) patients received medical rescue therapy (27% ciclosporin, 27% anti-tumour necrosis factor, compared with 27% ciclosporin in 1992-1993 (p=0.0015). Admission C reactive protein (CRP) (false discovery rate, p=0.00066), albumin (0.0066) and UCEIS scores (0.015) predicted steroid non-response. A four-point model was developed involving CRP of ≥100 mg/L (one point), albumin of ≤25 g/L (one point), and UCEIS score of ≥4 (1 point) or ≥7 (2 points). Patients scoring 0, 1, 2, 3 and 4 in the validation cohorts had steroid response rates of 100, 75.0%, 54.9%, 18.2% and 0%, respectively. Scoring of ≥3 was 84% (95% CI 0.70 to 0.98) predictive of steroid failure (OR 11.9, 95% CI 10.8 to 13.0). Colectomy rates in the validation cohorts were were 8%-11%. CONCLUSIONS: Emergency colectomy rates for ASC have halved in 25 years to 8%-15% worldwide. Patients who will not respond to corticosteroids are readily identified on admission and may be prioritised for early intensification of therapy.

Patient-reported Outcomes: the ICHOM Standard Set for Inflammatory Bowel Disease in Real-life Practice Helps Quantify Deficits in Current Care.

BACKGROUND: Patient-reported outcome measures [PROMs] are key to documenting outcomes that matter most to patients and are increasingly important to commissioners of health care seeking value. We report the first series of the ICHOM Standard Set for Inflammatory Bowel Disease [IBD]. METHODS: Patients treated for ulcerative colitis [UC] or Crohn's disease [CD] in our centre were offered enrolment into the web-based TrueColours-IBD programme. Through this programme, e-mail prompts linking to validated questionnaires were sent for symptoms, quality of life, and ICHOM IBD outcomes. RESULTS: The first 1299 consecutive patients enrolled [779 UC, 520 CD] were studied with median 270 days of follow-up (interquartile range [IQR] 116, 504). 671 [52%] were female, mean age 42 years (standard deviation [sd] 16), mean body mass index [BMI] 26 [sd 5.3]. At registration, 483 [37%] were using advanced therapies. Median adherence to fortnightly quality of life reporting and quarterly outcomes was 100% [IQR 48, 100%] and 100% [IQR 75, 100%], respectively. In the previous 12 months, prednisolone use was reported by 229 [29%] patients with UC vs 81 [16%] with CD, p <0.001; 202 [16%] for <3 months; and 108 [8%] for >3 months. An IBD-related intervention was reported by 174 [13%] patients, and 80 [6%] reported an unplanned hospital admission. There were high rates of fatigue [50%] and mood disturbance [23%]. CONCLUSIONS: Outcomes reported by patients illustrate the scale of the therapeutic deficit in current care. Proof of principle is demonstrated that PROM data can be collected continuously with little burden on health care professionals. This may become a metric for quality improvement programmes or to compare outcomes.

Emerging inflammatory bowel disease demographics, phenotype, and treatment in South Asia, South-East Asia, and Middle East: Preliminary findings from the Inflammatory Bowel Disease-Emerging Nations' Consortium.

BACKGROUND AND AIM: Inflammatory bowel disease (IBD) is emerging in the newly industrialized countries of South Asia, South-East Asia, and the Middle East, yet epidemiological data are scarce. METHODS: We performed a cross-sectional study of IBD demographics, disease phenotype, and treatment across 38 centers in 15 countries of South Asia, South-East Asia, and Middle East. Intergroup comparisons included gross national income (GNI) per capita. RESULTS: Among 10 400 patients, ulcerative colitis (UC) was twice as common as Crohn's disease (CD), with a male predominance (UC 6678, CD 3495, IBD unclassified 227, and 58% male). Peak age of onset was in the third decade, with a low proportion of elderly-onset IBD (5% age > 60). Familial IBD was rare (5%). The extent of UC was predominantly distal (proctitis/left sided 67%), with most being treated with mesalamine (94%), steroids (54%), or immunomodulators (31%). Ileocolic CD (43%) was the commonest, with low rates of perianal disease (8%) and only 6% smokers. Diagnostic delay for CD was common (median 12 months; interquartile range 5-30). Treatment of CD included mesalamine, steroids, and immunomodulators (61%, 51%, and 56%, respectively), but a fifth received empirical antitubercular therapy. Treatment with biologics was uncommon (4% UC and 13% CD), which increased in countries with higher GNI per capita. Surgery rates were 0.1 (UC) and 2 (CD) per 100 patients per year. CONCLUSIONS: The IBD-ENC cohort provides insight into IBD in South-East Asia and the Middle East, but is not yet population based. UC is twice as common as CD, familial disease is uncommon, and rates of surgery are low. Biologic use correlates with per capita GNI.

An Integrated Taxonomy for Monogenic Inflammatory Bowel Disease.

BACKGROUND & AIMS: Monogenic forms of inflammatory bowel disease (IBD) illustrate the essential roles of individual genes in pathways and networks safeguarding immune tolerance and gut homeostasis. METHODS: To build a taxonomy model, we assessed 165 disorders. Genes were prioritized based on penetrance of IBD and disease phenotypes were integrated with multi-omics datasets. Monogenic IBD genes were classified by (1) overlapping syndromic features, (2) response to hematopoietic stem cell transplantation, (3) bulk RNA-sequencing of 32 tissues, (4) single-cell RNA-sequencing of >50 cell subsets from the intestine of healthy individuals and patients with IBD (pediatric and adult), and (5) proteomes of 43 immune subsets. The model was validated by addition of newly identified monogenic IBD defects. As a proof-of-concept, we explore the intersection between immunometabolism and antimicrobial activity for a group of disorders (G6PC3/SLC37A4). RESULTS: Our quantitative integrated taxonomy defines the cellular landscape of monogenic IBD gene expression across 102 genes with high and moderate penetrance (81 in the model set and 21 genes in the validation set). We illustrate distinct cellular networks, highlight expression profiles across understudied cell types (e.g., CD8+ T cells, neutrophils, epithelial subsets, and endothelial cells) and define genotype-phenotype associations (perianal disease and defective antimicrobial activity). We illustrate processes and pathways shared across cellular compartments and phenotypic groups and highlight cellular immunometabolism with mammalian target of rapamycin activation as one of the converging pathways. There is an overlap of genes and enriched cell-specific expression between monogenic and polygenic IBD. CONCLUSION: Our taxonomy integrates genetic, clinical and multi-omic data; providing a basis for genomic diagnostics and testable hypotheses for disease functions and treatment responses.

Multinational evaluation of clinical decision-making in the treatment and management of mild-to-moderate ulcerative colitis.

OBJECTIVES: To understand current thinking and clinical decision-making in the treatment and management of patients with mild-to-moderate ulcerative colitis (UC). METHODS: This multinational, survey-based study was conducted in 2021. Two meetings were held, involving 11 IBD specialists, that used a series of questions and discussion to identify all factors possibly related to the management of UC. The importance of identified factors was assessed using an online questionnaire covering three scenarios - active disease, remission and patient empowerment. Each factor was scored on a scale of 0 (very-unimportant) to 100 (very-important) within each scenario, by a separate group of healthcare professionals working in IBD. RESULTS: A total of 157 individual factors were identified by the 11 IBD specialists and scored in the three scenarios by 56 respondents (52; 93% specialist gastroenterologists) from Europe and North America (25; 45%), South America (19; 34%) and the Middle East, Asia and Australia (12; 21%). For all scenarios, factors related to educating patients regarding UC and its treatment and understanding of patient goals ranked highest, ahead of clinical considerations regarding disease activity and treatment history. Setting realistic short-term treatment targets was a key consideration. 5-ASA optimisation and use of faecal calprotectin monitoring were core strategies across the three scenarios tested. Support for patients during longer-term management of their disease, starting from initial flare, was an important recurring theme. CONCLUSION: The current management approach for mild-to-moderate UC was found to be guided primarily by the patient's perspectives and goals, alongside assessment of their medical and disease history.

Defactinib inhibits PYK2 phosphorylation of IRF5 and reduces intestinal inflammation.

Interferon regulating factor 5 (IRF5) is a multifunctional regulator of immune responses, and has a key pathogenic function in gut inflammation, but how IRF5 is modulated is still unclear. Having performed a kinase inhibitor library screening in macrophages, here we identify protein-tyrosine kinase 2-beta (PTK2B/PYK2) as a putative IRF5 kinase. PYK2-deficient macrophages display impaired endogenous IRF5 activation, leading to reduction of inflammatory gene expression. Meanwhile, a PYK2 inhibitor, defactinib, has a similar effect on IRF5 activation in vitro, and induces a transcriptomic signature in macrophages similar to that caused by IRF5 deficiency. Finally, defactinib reduces pro-inflammatory cytokines in human colon biopsies from patients with ulcerative colitis, as well as in a mouse colitis model. Our results thus implicate a function of PYK2 in regulating the inflammatory response in the gut via the IRF5 innate sensing pathway, thereby opening opportunities for related therapeutic interventions for inflammatory bowel diseases and other inflammatory conditions.

Efficacy and safety of oral Pentasa (prolonged-release mesalazine) in mild-to-moderate ulcerative colitis: a systematic review and meta-analysis.

BACKGROUND: Pentasa (prolonged-release mesalazine [5-ASA]) has been available for >30 years as an effective treatment for mild-to-moderate ulcerative colitis (UC). A systematic literature review and meta-analysis was undertaken to provide an up-to-date evaluation of oral Pentasa efficacy and safety for induction and maintenance of remission. METHODS: Literature searches were conducted in PubMed, Embase and Cochrane databases, from inception to 02 December 2020. Unpublished studies were also sourced. Meta-analyses using a random-effects model and Bayesian inference compared Pentasa (tablets, granules, capsules) against placebo and other 5-ASAs. RESULTS: Twelve studies involving 3674 patients treated with Pentasa were identified. Pentasa 2-4 g/day was superior to placebo at inducing (absolute risk difference [ARD] at 8 weeks 0.14, 95% CI 0.07‒0.21; p < .001) and maintaining (ARD 6-12 months 0.18, 95% CI 0.04‒0.33; p < .05) remission (clinical/endoscopic). Against other 5-ASAs, Pentasa had similar efficacy for induction (ARD <0.001, 95% CI -0.05‒0.05) and maintenance (ARD 0.01, 95% CI -0.07‒0.08) treatment using randomized controlled trial data. Upon inclusion of real-world study data, Pentasa was significantly better at maintaining remission compared both to Eudragit-S mesalazine and sulfasalazine (ARD 0.04, 95% CI 0.02‒0.06; p < .001). Pentasa (1-4 g/day) had similar treatment-related adverse event rates to placebo (ARD 0.02, 95% CI -0.03‒0.06) and Eudragit-L/S mesalazines (2.25-3 vs 2.4-3 g/day, respectively; ARD -0.03, 95% CI -0.12‒0.05), but was better tolerated than sulfasalazine (3 g/day) (ARD 0.07, 95% CI 0.003‒0.14; p < .05). CONCLUSION: This study confirms oral Pentasa is efficacious and well-tolerated in treating active UC and maintaining remission. The availability of multiple forms of Pentasa supports physicians' ability to individualize treatment and optimize dosing to improve outcomes.

Interferon-Gamma-Producing CD8+ Tissue Resident Memory T Cells Are a Targetable Hallmark of Immune Checkpoint Inhibitor-Colitis.

BACKGROUND & AIMS: The pathogenesis of immune checkpoint inhibitor (ICI)-colitis remains incompletely understood. We sought to identify key cellular drivers of ICI-colitis and their similarities to idiopathic ulcerative colitis, and to determine potential novel therapeutic targets. METHODS: We used a cross-sectional approach to study patients with ICI-colitis, those receiving ICI without the development of colitis, idiopathic ulcerative colitis, and healthy controls. A subset of patients with ICI-colitis were studied longitudinally. We applied a range of methods, including multiparameter and spectral flow cytometry, spectral immunofluorescence microscopy, targeted gene panels, and bulk and single-cell RNA sequencing. RESULTS: We demonstrate CD8+ tissue resident memory T (TRM) cells are the dominant activated T cell subset in ICI-colitis. The pattern of gastrointestinal immunopathology is distinct from ulcerative colitis at both the immune and epithelial-signaling levels. CD8+ TRM cell activation correlates with clinical and endoscopic ICI-colitis severity. Single-cell RNA sequencing analysis confirms activated CD8+ TRM cells express high levels of transcripts for checkpoint inhibitors and interferon-gamma in ICI-colitis. We demonstrate similar findings in both anti-CTLA-4/PD-1 combination therapy and in anti-PD-1 inhibitor-associated colitis. On the basis of our data, we successfully targeted this pathway in a patient with refractory ICI-colitis, using the JAK inhibitor tofacitinib. CONCLUSIONS: Interferon gamma-producing CD8+ TRM cells are a pathological hallmark of ICI-colitis and a novel target for therapy.

Randomised clinical trial: exclusive enteral nutrition versus standard of care for acute severe ulcerative colitis.

BACKGROUND: Intravenous corticosteroids are the mainstay of therapy for acute severe ulcerative colitis (ASUC), but 30%-40% of patients fail to respond. AIM: To investigate the effectiveness of exclusive enteral nutrition (EEN) as adjunctive therapy to intravenous corticosteroids in patients with ASUC. METHODS: This was an open-label randomised controlled trial, in which patients who were admitted with ASUC between August 2018 and May 2020 were randomised 1:1 to EEN or standard of care (SOC). Patients on EEN received a semi-elemental formula for 7 days along with SOC. The primary outcome was corticosteroid failure, defined by the need for salvage medical therapy or colectomy. Faecal microbial analysis was performed on day 1 and day 7 by 16s ribosomal RNA sequencing in some patients. RESULTS: Of 62 patients (mean age 35.3 ± 12.1 years, 40% male), 32 were randomised to EEN and 30 to SOC. Corticosteroid failure was lower on EEN compared to SOC (intention-to-treat analysis 25% vs 43%, P = 0.051; per protocol analysis 19% vs 43%, P = 0.04), without any difference in colectomy rate (9% vs 13%; P = 0.41). Patients on EEN had a shorter hospital stay [median (range) 10 (8-17) vs 13 (8-24) days; P = 0.04], higher day 7 albumin level (34 ± 4 vs 29 ± 3 g/L, P < 0.01), greater reduction in serum C-reactive protein and faecal calprotectin levels (both P = 0.04) and a lower composite outcome of colectomy/hospitalisation at 6 months (16% vs 39%; P = 0.045) compared to SOC. Patients on EEN showed increased abundance of Erysipelotrichaceae on day 7, with reduced Bifidobacterium and Veillonellaceae compared to SOC. CONCLUSIONS: EEN for 7 days may augment corticosteroid responsiveness in patients with ASUC. (REF/2018/05/019844; CTRI/2020/06/025989).

Gut microbiome diversity in acute severe colitis is distinct from mild to moderate ulcerative colitis.

BACKGROUND AND AIM: Although the gut microbiome of patients with ulcerative colitis (UC) has been characterized, no study has characterized the gut microbiome in acute severe colitis (ASC). We compared the gut microbiome of patients with UC, ASC, and healthy controls (HCs). METHODS: Patients with mild to moderate UC (n = 24), ASC (n = 19 with 21 episodes) and HCs (n = 50) were recruited prospectively. A 16SrDNA amplicon approach was used to explore gut microbial diversity and taxonomic repertoires. UC was diagnosed using European Crohn's and Colitis Organization guidelines, and ASC was diagnosed using Truelove and Witts' criteria. RESULTS: The normalized alpha diversity was significantly lower in ASC than mild-moderately active UC (P < 0.05) or HC (P < 0.001). The gut microbiome in ASC was highly unstable, as characterized by high intracohort variation (analyzed using J-divergence measure), which was significantly greater than in UC or HC. On principal coordinate analysis, the microbiome of HC and UC were similar, with the ASC cohort being distinct from both. Comparison of ranked abundances identified four distinct clusters of genera (G1, G2, G3, and G4), with specific trends in their abundance across three groups: G1/G2A clusters had the least, whereas G3 had the highest abundance in the ASC cohort. CONCLUSIONS: Gut microbial diversity is lower in ASC than mild-moderate UC or HCs. Gut microbiome composition is increasingly unstable in ASC, with a distinct abundance of specific genera varying between HCs and ASC. Mild-moderate UC lies within the spectrum.

Targeted versus universal tuberculosis chemoprophylaxis in 1968 patients with inflammatory bowel disease receiving anti-TNF therapy in a tuberculosis endemic region.

BACKGROUND: Anti-tumour necrosis factor (anti-TNF) therapy increases the risk of tuberculosis (TB). Given limitations of screening techniques, it remains uncertain if patients receiving anti-TNF in TB endemic regions should be screened for latent infection with chemoprophylaxis restricted to those with proven infection, or if all patients should receive chemoprophylaxis. AIMS: To compare the incidence of active TB with infliximab (IFX) following targeted and universal TB chemoprophylaxis, and to determine the rates of adverse events (AE) related to TB chemoprophylaxis METHODS: A multi-centre retrospective cohort study was performed at 18 hospitals in China of 1968 adult patients with IBD receiving IFX from 2009 to 2017. TB screening prior to IFX was performed with chest X-ray and/or computed tomography [CT] and immune reactivity testing (interferon-γ release assay and/or tuberculin skin test). Patients were followed-up for a minimum of 3 months after IFX discontinuation, or until last hospital visit if IFX therapy was ongoing. Targeted strategy was defined as TB chemoprophylaxis only for patients with a positive latent TB screen, with universal strategy defined as TB chemoprophylaxis for all patients. RESULTS: Mean follow-up was 1.07 ± 0.87 years with a total follow-up of 2102 patient-years. There were 1433 patients in the targeted and 483 patients in the universal TB chemoprophylaxis groups, with no significant difference in the incidence rates of active TB between groups (673.3 per 100 000 population per year vs 891.5 per 100 000 population per year, P = 0.60). In the targeted group, 55/1433 patients received TB chemoprophylaxis compared with 483/483 in the universal group, with significantly fewer AEs related to TB chemoprophylaxis in the targeted compared to the universal group (0.35% (5/1433) vs 6.8% (33/483), P < 0.05). CONCLUSIONS: In this study of patients receiving IFX in a TB endemic area, universal chemoprophylaxis was not associated with a reduced risk of active TB when compared to a targeted chemoprophylaxis strategy, and AEs were more common. This supports the use of targeted TB chemoprophylaxis when anti-TNF therapy is initiated in TB endemic regions.