Ian D. Arnott

Toward an Integrated Clinical, Molecular and Serological Classification of Inflammatory Bowel Disease: Report of a Working Party of the 2005 Montreal World Congress of Gastroenterology

The discovery of a series of genetic and serological markers associated with disease susceptibility and phenotype in inflammatory bowel disease has led to the prospect of an integrated classification system involving clinical, serological and genetic parameters. The Working Party has reviewed current clinical classification systems in Crohns disease, ulcerative colitis and indeterminate colitis, and provided recommendations for clinical classification in practice. Progress with respect to integrating serological and genetic markers has been examined in detail, and the implications are discussed. While an integrated system is not proposed for clinical use at present, the introduction of a widely acceptable clinical subclassification is strongly advocated, which would allow detailed correlations among serotype, genotype and clinical phenotype to be examined and confirmed in independent cohorts of patients and, thereby, provide a vital foundation for future work.

Guidelines for the management of inflammatory bowel disease in adults

The management of inflammatory bowel disease represents a key component of clinical practice for members of the British Society of Gastroenterology (BSG). There has been considerable progress in management strategies affecting all aspects of clinical care since the publication of previous BSG guidelines in 2004, necessitating the present revision. Key components of the present document worthy of attention as having been subject to re-assessment, and revision, and having direct impact on practice include: The data generated by the nationwide audits of inflammatory bowel disease (IBD) management in the UK in 2006, and 2008. The publication of ‘Quality Care: service standards for the healthcare of people with IBD’ in 2009. The introduction of the Montreal classification for Crohns disease and ulcerative colitis. The revision of recommendations for the use of immunosuppressive therapy. The detailed analysis, guidelines and recommendations for the safe and appropriate use of biological therapies in Crohns disease and ulcerative colitis. The reassessment of the role of surgery in disease management, with emphasis on the importance of multi-disciplinary decision-making in complex cases. The availablity of new data on the role of reconstructive surgery in ulcerative colitis. The cross-referencing to revised guidelines for colonoscopic surveillance, for the management of metabolic bone disease, and for the care of children with inflammatory bowel disease. Use of the BSG discussion forum available on the BSG website to enable ongoing feedback on the published document http://www.bsg.org.uk/forum (accessed Oct 2010). The present document is intended primarily for the use of clinicians in the United Kingdom, and serves to replace the previous BSG guidelines in IBD, while complementing recent consensus statements published by the European Crohns and Colitis Organisation (ECCO) https://www.ecco-ibd.eu/index.php (accessed Oct 2010).

Infliximab in moderately severe glucocorticoid resistant ulcerative colitis: a randomised controlled trial

Background: Tumour necrosis factor production is increased in the mucosa of patients with active ulcerative colitis. The benefits of infliximab in Crohn’s disease are established. We investigated its efficacy in ulcerative colitis. Methods: We conducted a randomised placebo controlled trial of infliximab (5 mg/kg) in the treatment of glucocorticoid resistant ulcerative colitis. Infusions were given at weeks 0 and 2. Disease activity and quality of life were recorded over eight weeks of follow up. Remission was defined as an ulcerative colitis symptom score (UCSS) of ⩽2 and/or Baron score of 0 at week 6. Patients not in remission were offered open label infliximab 10 mg/kg and reviewed two weeks later. Results: After two weeks, there was no statistically significant difference between the infliximab and placebo groups in the proportion of patients with a Baron score of 0 (13% (3/23) v 5% (1/19) (95% confidence interval (CI) −9% to 24%); p=0.74). After six weeks, remission (UCSS ⩽2) rates were 39% (9/23) versus 30% (6/20) (95% CI −19 to 34%; p=0.76). The median improvement in UCSS was 3 for the infliximab group and 2.5 for the placebo group (p=0.82, Mann-Whitney U test). A Baron score of 0 was likely in either group (26% (6/23) v 30% (6/20) (95% CI −30% to 23%); p=0.96). Improvement in the IBDQ and EuroQol was not significantly different between the groups (p=0.22 and 0.3, respectively, Mann-Whitney U test). Twenty eligible patients were given open labelled infusions. Remission was achieved in 3/11 (27%) patients initially treated with infliximab and in 1/9 (11%) patients treated with placebo. Conclusion: These data do not support the use of infliximab in the management of moderately active glucocorticoid resistant ulcerative colitis.

Sero-reactivity to microbial components in Crohn's disease is associated with disease severity and progression, but not NOD2/CARD15 genotype

BACKGROUND AND AIMS:Antibodies directed against the porin protein C of Escherichia coli (anti-OmpC) and Pseudomonas fluorescens (anti-I2) have recently been described in Crohns disease (CD). Those directed against Saccharomyces cerevisiae (ASCA) and the perinuclear component of neutrophils (pANCA) have been more widely studied and may be of diagnostic importance. We aimed to assess the frequency of anti-OmpC, anti-I2, ASCA, and pANCA, in an independent Scottish CD cohort, establish phenotypic associations, and compare with a U.S. cohort.METHODS:One hundred and forty-two well-characterized CD patients (76 females, median age 39 yr (17–88)) were studied. CD was classified by the Vienna classification. Sera were assayed for anti-OmpC, anti-I2, ASCA, and pANCA. Allele specific primers were used for NOD2/CARD15 genotyping.RESULTS:Anti-OmpC, anti-I2, ASCA, and pANCA were present in sera from 37%, 52%, 39%, and 14% of CD patients, respectively. Multivariate analysis demonstrated independent associations of anti-OmpC to be progression of disease type (p= 0.005) and long disease duration (p= 0.002), and those of anti-I2 to be long disease duration (p= 0.002) and the need for surgery (p= 0.033). ASCA were associated with disease progression (p < 0.001). When the presence and magnitude of all antibody responses were considered, reactivity to microbial components was associated with long disease duration (p < 0.001), progression of disease type (p < 0.001), penetrating disease (p= 0.008), small bowel disease (p < 0.02), and the need for surgery (p < 0.001). There was no association of antibody status to NOD2/CARD15 genotype.CONCLUSION:Reactivity to microbial components is associated with severe CD characterized by small bowel involvement, frequent disease progression, longer disease duration, and greater need for intestinal surgery.

NOD2/CARD15, TLR4 and CD14 mutations in Scottish and Irish Crohn's disease patients: evidence for genetic heterogeneity within Europe?

NOD2/caspase recruitment domain (CARD)15 variants are identified in up to 50% of Crohns disease (CD) patients. Functional variants of toll-like receptor-4 (TLR4) and CD14 genes may also be relevant to disease pathophysiology. We aimed to assess the contribution of NOD2/CARD15, TLR4 and CD14 variants in Scottish and Irish CD patients. In all, 612 patients with well-characterised inflammatory bowel disease (252 Scottish CD, 247 Scottish UC, 113 Irish CD) and 304 controls were genotyped for variants of NOD2/CARD15 (1007fsinsC, G908R, R702W, P268S), TLR4 (A299G) and CD14 (T-159C). Genotype–phenotype analyses were performed. Variant 1007fsinsC (P=0.003) and G908R (P=0.008) but not R702W (P=0.269) alleles were more prevalent in Scottish CD (4.7, 1.8 and 7.1%, respectively) than Scottish control (2.3, 0.3 and 5.4%). CD allelic frequencies were lower than the series from Europe (P<0.00001) and North America (P<0.00001) but not Scandinavia (P<0.7). Associations were identified with age at diagnosis (P=0.002), ileal disease (P<0.02), penetrating disease (P=0.04) and inflammatory joint disease (P<0.02). TLR4 and CD14 variants did not differ between CD and controls. In conclusion, we present compelling evidence for genetic heterogeneity within Europe. These NOD2/CARD15 variants have a minor contribution in Scottish and Irish CD patients, consistent with an emerging pattern from Northern Europe.

An analysis of factors influencing short‐term and sustained response to infliximab treatment for Crohn's disease

Background: 59–81% of patients given infliximab for Crohns disease will respond. Although now in widespread use, little consensus exists regarding the optimal place in patient care. Recently developed guidelines have identified need for markers that predict response.

The efficacy of corticosteroid therapy in inflammatory bowel disease: analysis of a 5‐year UK inception cohort

Corticosteroids remain the mainstay of first‐line therapy in active inflammatory bowel disease.

Fecal Calprotectin Predicts the Clinical Course of Acute Severe Ulcerative Colitis

OBJECTIVES:Calprotectin is a granulocyte neutrophil-predominant cytosolic protein. Fecal concentrations are elevated in intestinal inflammation and may predict relapse in quiescent inflammatory bowel disease. We aim to investigate fecal calprotectin (FC) as a biomarker in predicting the clinical course of acute severe ulcerative colitis (ASUC).METHODS:In 90 patients with ASUC requiring intensive in-patient medical therapy (January 2005–September 2007), we investigated the discriminant ability of FC to predict colectomy and corticosteroid and infliximab nonresponse. All patients received parenteral corticosteroids as first-line treatment; 21 (23.3%) were also treated with infliximab (5 mg/kg), after failure of corticosteroid therapy.RESULTS:Of 90 patients, 31 (34.4%) required colectomy, including 11 (52.4%) of those treated with infliximab. Overall FC was high (1,020.0 μg/g interquartile range: 601.5–1,617.5). FC was significantly higher in patients requiring colectomy (1,200.0 vs. 887.0; P=0.04), with a trend toward significance when comparing corticosteroid nonresponders and responders (1,100.0 vs. 863.5; P=0.08), as well as between infliximab nonresponders and responders (1,795.0 vs. 920.5; P=0.06). Receiver–operator characteristic curve analysis yielded an area under the curve of 0.65 to predict colectomy (P=0.04), with a maximum likelihood ratio of 9.23, specificity 97.4%, and sensitivity 24.0% at a cutoff point of 1,922.5 μg/g. Kaplan–Meier analyses showed that using 1,922.5 μg/g over a median follow-up of 1.10 years, 87% of patients will need subsequent colectomy.CONCLUSIONS:This is the first data set to demonstrate that FC levels are dramatically elevated in severe UC. These data raise the possibility that this biomarker can predict response to first or second-line medical therapy in this setting.

Regional Variation in Gene Expression in the Healthy Colon is Dysregulated in Ulcerative Colitis

Objective: To investigate differential intestinal gene expression in patients with ulcerative colitis and in controls. Design: Genome-wide expression study (41 058 expression sequence tags, 215 biopsies). Setting: Western General Hospital, Edinburgh, UK, and Genentech, San Francisco, USA. Patients: 67 patients with ulcerative colitis and 31 control subjects (23 normal subjects and 8 patients with inflamed non-inflammatory bowel disease biopsies). Interventions: Paired endoscopic biopsies were taken from 5 specific anatomical locations for RNA extraction and histology. The Agilent microarray platform was used and confirmation of results was undertaken by real time polymerase chain reaction and immunohistochemistry. Results: In healthy control biopsies, cluster analysis showed differences in gene expression between the right and left colon. (χ2 = 25.1, p<0.0001). Developmental genes, homeobox protein A13 (HOXA13), (p = 2.3×10−16), HOXB13 (p<1×10−45), glioma-associated oncogene 1 (GLI1) (p = 4.0×10−24), and GLI3 (p = 2.1×10−28) primarily drove this separation. When all ulcerative colitis biopsies and control biopsies were compared, 143 sequences had a fold change of >1.5 in the ulcerative colitis biopsies (0.01>p>10−45) and 54 sequences had a fold change of <−1.5 (0.01>p>10−20). Differentially upregulated genes in ulcerative colitis included serum amyloid A1 (SAA1) (p<10−45) the alpha defensins 5 and 6 (DEFA5 and 6) (p = 0.00003 and p = 6.95×10−7, respectively), matrix metalloproteinase 3 (MMP3) (p = 5.6×10−10) and MMP7 (p = 2.3×10−7). Increased DEFA5 and 6 expression was further characterised to Paneth cell metaplasia by immunohistochemistry and in situ hybridisation. Sub-analysis of the inflammatory bowel disease 2 (IBD2) and IBD5 loci, and the ATP-binding cassette (ABC) transporter genes revealed a number of differentially regulated genes in the ulcerative colitis biopsies. Conclusions: Key findings are the expression gradient in the healthy adult colon and the involvement of novel gene families, as well as established candidate genes in the pathogenesis of ulcerative colitis.

A retrospective analysis of the efficacy and safety of infliximab as rescue therapy in acute severe ulcerative colitis

Background  Forty per cent of patients with acute severe ulcerative colitis will not respond to intravenous corticosteroids and require second‐line medical therapy or colectomy. A recent controlled trial has suggested that infliximab may be effective as rescue therapy.