The Toronto IBD Global Endoscopic Reporting [TIGER] Score: A Single, Easy to Use Endoscopic Score for Both Crohn's Disease and Ulcerative Colitis Patients.

BACKGROUND AND AIMS: We constructed the Toronto IBD Global Endoscopic Reporting [TIGER] score for inflammatory bowel disease [IBD]. The aim of our study was to develop and validate the TIGER score against faecal calprotectin [FC], C-reactive protein [CRP], and IBD Disk. METHODS: A cross-sectional study was performed among 113 adult patients (60 Crohn's disease [CD] and 53 ulcerative colitis [UC]). In the development and usability phase, blinded IBD experts reviewed and graded ileocolonoscopy videos. In the validity phase the TIGER score was compared with: [1] the Simple endoscopic Score for CD [SES-CD] and the Mayo endoscopic score in CD and UC, respectively; [2] FC and CRP; and [3] IBD Disk. RESULTS: Inter-observer reliability of the TIGER score per segment between reviewers was excellent: interclass correlation coefficient [ICC] = 0.94 [95% CI: 0.92-0.96]. For CD patients, overall agreement per segment between SES-CD and TIGER was 91% [95% CI: 84-95] with kappa coefficient 0.77 [95% CI: 0.63-0.91]. There was a significant correlation between TIGER and CRP [p <0.0083], and TIGER and FC [p <0.0001]. In addition, there was significant correlation between TIGER and IBD Disk [p <0.0001]. For UC patients, overall agreement per segment between Mayo endoscopic score and TIGER was 84% [95% CI: 74%-90%] and kappa coefficient 0.60 [95% CI: 0.42-0.808]. There was a significant correlation between TIGER and FC [p <0.0001]. There was a significant correlation between TIGER and IBD Disk [p <0.0001]. CONCLUSIONS: The TIGER score is a reliable and simple novel endoscopic score that can be used for both CD and UC patients and captures full endoscopic disease burden.

Higher Adalimumab Drug Levels are Associated with Mucosal Healing in Patients with Crohn's Disease.

BACKGROUND AND AIMS: The current approach to managing the loss of response to anti-tumour necrosis factor (TNF) agents is generally empirical. Prior studies have suggested that adalimumab levels of >4.9 µg/mL are required to achieve clinical remission. Our aim was to identify an optimal adalimumab level to achieve endoscopic healing in Crohn's disease (CD). METHODS: A cohort of 60 CD patients treated with adalimumab between 2005 and 2013 were reviewed for the study. Demographic and clinical information was obtained from chart review and patient interview. Disease activity was determined using the Harvey-Bradshaw index (HBI), ileocolonoscopy reports and C-reactive protein (CRP) levels. Clinical remission was defined as HBI <5. Endoscopic remission/mucosal healing (MH) was defined as the absence of any ulceration in all ileocolonic segments. Trough adalimumab levels and adalimumab antibody levels were tested using a liquid-phase mobility shift assay. RESULTS: Lower median CRP was significantly associated with MH 1.2mg/dl vs no MH 14.4mg/dl (p = 6.93×10(-6)). Higher adalimumab trough level was significantly associated with MH (median 14.7 µg/mL in those with MH vs 3.4 µg/mL in those without, p = 6.25×10(-5)). Higher adalimumab trough level was also significantly associated with the combined outcome of clinical and endoscopic remission (median 13.0 vs 4.8 µg/mL, p = 5.36×10(-3)). A cut-off of 8.14 µg/ml best discriminated subjects with MH from those without MH, with sensitivity and specificity of 91.4 and 76.0%, respectively (positive and negative predictive values 84.2 and 86.4%, respectively). CONCLUSIONS: Higher adalimumab levels were significantly associated with MH. This study suggests that attaining MH alone or a combined outcome of clinical and endoscopic remission is more likely to occur in those patients who achieve an adalimumab trough level of at least 8.14 µg/mL.

Characterization of Intestinal Microbiota in Ulcerative Colitis Patients with and without Primary Sclerosing Cholangitis.

BACKGROUND AND AIMS: There is an unexplained association between ulcerative colitis [UC] and primary sclerosing cholangitis [PSC], with the intestinal microbiota implicated as an important factor. The study aim was to compare the structure of the intestinal microbiota of patients with UC with and without PSC. METHODS: UC patients with PSC [PSC-UC] and without PSC [UC] were identified from biobanks at Oslo University Hospital, Foothills Hospital Calgary and Mount Sinai Hospital Toronto. Microbial DNA was extracted from colonic tissue and sequencing performed of the V4 region of the 16S rRNA gene on Illumina MiSeq. Sequences were assigned to operational taxonomic units [OTUs] using Quantitative Insights Into Microbial Ecology [QIIME]. Microbial alpha diversity, beta diversity, and relative abundance were compared between PSC-UC and UC phenotypes. RESULTS: In all, 31 PSC-UC patients and 56 UC patients were included. Principal coordinate analysis [PCoA] demonstrated that city of sample collection was the strongest determinant of taxonomic profile. In the Oslo cohort, Chao 1 index was modestly decreased in PSC-UC compared with UC [p = 0.04] but did not differ significantly in the Calgary cohort. No clustering by PSC phenotype was observed using beta diversity measures. For multiple microbial genera there were nominally significant differences between UC and PSC-UC, but results were not robust to false-discovery rate correction. CONCLUSIONS: No strong PSC-specific microbial associations in UC patients consistent across different cohorts were identified. Recruitment centre had a strong effect on microbial composition. Future studies should include larger cohorts to increase power and the ability to control for confounding factors.

A validated web-based tool to display individualised Crohn's disease predicted outcomes based on clinical, serologic and genetic variables.

BACKGROUND: Early treatment for Crohn's disease (CD) with immunomodulators and/or anti-TNF agents improves outcomes in comparison to a slower 'step up' algorithm. However, there remains a limited ability to identify those who would benefit most from early intensive therapy. AIM: To develop a validated, individualised, web-based tool for patients and clinicians to visualise individualised risks for developing Crohn's disease complications. METHODS: A well-characterised cohort of adult patients with CD was analysed. Available data included: demographics; clinical characteristics; serologic immune responses; NOD2 status; time from diagnosis to complication; and medication exposure. Cox proportional analyses were performed to model the probability of developing a CD complication over time. The Cox model was validated externally in two independent CD cohorts. Using system dynamics analysis (SDA), these results were transformed into a simple graphical web-based display to show patients their individualised probability of developing a complication over a 3-year period. RESULTS: Two hundered and forty three CD patients were included in the final model of which 142 experienced a complication. Significant variables in the multivariate Cox model included small bowel disease (HR 2.12, CI 1.05-4.29), left colonic disease (HR 0.73, CI 0.49-1.09), perianal disease (HR 4.12, CI 1.01-16.88), ASCA (HR 1.35, CI 1.16-1.58), Cbir (HR 1.29, CI 1.07-1.55), ANCA (HR 0.77, CI 0.62-0.95), and the NOD2 frameshift mutation/SNP13 (HR 2.13, CI 1.33-3.40). The Harrell's C (concordance index for predictive accuracy of the model) = 0.73. When applied to the two external validation cohorts (adult n = 109, pediatric n = 392), the concordance index was 0.73 and 0.75, respectively, for adult and pediatric patients. CONCLUSIONS: A validated, web-based tool has been developed to display an individualised predicted outcome for adult patients with Crohn's disease based on clinical, serologic and genetic variables. This tool can be used to help providers and patients make personalised decisions about treatment options.

Selecting Therapeutic Targets in Inflammatory Bowel Disease (STRIDE): Determining Therapeutic Goals for Treat-to-Target.

OBJECTIVES: The Selecting Therapeutic Targets in Inflammatory Bowel Disease (STRIDE) program was initiated by the International Organization for the Study of Inflammatory Bowel Diseases (IOIBD). It examined potential treatment targets for inflammatory bowel disease (IBD) to be used for a "treat-to-target" clinical management strategy using an evidence-based expert consensus process. METHODS: A Steering Committee of 28 IBD specialists developed recommendations based on a systematic literature review and expert opinion. Consensus was gained if ≥75% of participants scored the recommendation as 7-10 on a 10-point rating scale (where 10=agree completely). RESULTS: The group agreed upon 12 recommendations for ulcerative colitis (UC) and Crohn's disease (CD). The agreed target for UC was clinical/patient-reported outcome (PRO) remission (defined as resolution of rectal bleeding and diarrhea/altered bowel habit) and endoscopic remission (defined as a Mayo endoscopic subscore of 0-1). Histological remission was considered as an adjunctive goal. Clinical/PRO remission was also agreed upon as a target for CD and defined as resolution of abdominal pain and diarrhea/altered bowel habit; and endoscopic remission, defined as resolution of ulceration at ileocolonoscopy, or resolution of findings of inflammation on cross-sectional imaging in patients who cannot be adequately assessed with ileocolonoscopy. Biomarker remission (normal C-reactive protein (CRP) and calprotectin) was considered as an adjunctive target. CONCLUSIONS: Evidence- and consensus-based recommendations for selecting the goals for treat-to-target strategies in patients with IBD are made available. Prospective studies are needed to determine how these targets will change disease course and patients' quality of life.

Review article: a clinician's guide for therapeutic drug monitoring of infliximab in inflammatory bowel disease.

BACKGROUND: Tumour necrosis factor (TNF)-antagonists have an established role in the treatment of inflammatory bowel diseases (IBDs), however, subtherapeutic drug levels and the formation of anti-drug antibodies (ADAs) may decrease their efficacy. AIM: The evidence supporting the use of therapeutic drug monitoring (TDM) based clinical algorithms for infliximab (IFX) and their role in clinical practice will be discussed. METHODS: The literature was reviewed to identify relevant articles on the measurement of IFX levels and antibodies-to-infliximab. RESULTS: Treatment algorithms for IBD have evolved from episodic monotherapy used in patients refractory to all other treatments, to long-term combination therapy initiated early in the disease course. Improved remission rates have been observed with this paradigm shift, nevertheless many patients ultimately lose response to therapy. Although empiric dose optimization or switching agents constitute the current standard of care for secondary failure, these interventions have not been applied in an evidence-based manner and are probably not cost-effective. Multiple TDM-based algorithms have been developed to identify patients that may benefit from measurement of IFX and ADA levels to guide adjustments to therapy. CONCLUSIONS: Therapeutic drug monitoring offers a rational approach to the management of secondary failure to IFX. This concept has gained momentum based on evidence from case series, cohort studies and post-hoc analyses of randomised controlled trials.

Predicting complicated Crohn's disease and surgery: phenotypes, genetics, serology and psychological characteristics of a population-based cohort.

BACKGROUND: Predictors of complicated Crohn's disease (CD), defined as stricturing or penetrating behaviour, and surgery have largely been derived from referral centre populations. AIM: To investigate whether serological markers, susceptibility genes or psychological characteristics are associated with complicated CD or surgery in a population-based cohort. METHODS: One hundred and eighty-two members of the Manitoba IBD Cohort with CD phenotyped using the Montreal classification underwent genetic and serological analysis at enrolment and after 5 years. One hundred and twenty-seven had paired sera at baseline and 5 years later and their data were used to predict outcomes at a median of 9.3 years. Serological analysis consisted of a seven antibody panel, and DNA was tested for CD-associated NOD2 variants (rs2066845,rs2076756,rs2066847), ATG16L1 (rs3828309, rs2241880) and IL23R (rs11465804). Psychological characteristics were assessed using semi-structured interviews and validated survey measures. RESULTS: Sixty-five per cent had complicated CD and 42% underwent surgery. Multivariate analysis indicated that only ASCA IgG-positive serology was predictive of stricturing/penetrating behaviour (OR = 3.01; 95% CI: 1.28-7.09; P = 0.01) and ileal CD (OR = 2.2; 95% CI: 1.07-4.54, P = 0.03). Complicated CD behaviour was strongly associated with surgery (OR = 5.6; 95% CI: 2.43-12.91; P < 0.0001), whereas in multivariate analysis, only ASCA IgG was associated (OR = 2.66; 95% CI, 1.40-5.06, P = 0.003). ASCA titre results were similar at baseline and follow-up. Psychological characteristics were not significantly associated with disease behaviour, serological profile or genotype. CONCLUSIONS: ASCA IgG at baseline was significantly associated with stricturing/penetrating disease at 9-10 years from diagnosis. Stricturing/penetrating disease was significantly associated with surgery. In a model including serology, the genotypes assessed did not significantly associate with complicated disease or surgery.

Extended haplotype association study in Crohn's disease identifies a novel, Ashkenazi Jewish-specific missense mutation in the NF-κB pathway gene, HEATR3.

The Ashkenazi Jewish population has a several-fold higher prevalence of Crohn's disease (CD) compared with non-Jewish European ancestry populations and has a unique genetic history. Haplotype association is critical to CD etiology in this population, most notably at NOD2, in which three causal, uncommon and conditionally independent NOD2 variants reside on a shared background haplotype. We present an analysis of extended haplotypes that showed significantly greater association to CD in the Ashkenazi Jewish population compared with a non-Jewish population (145 haplotypes and no haplotypes with P-value <10(-3), respectively). Two haplotype regions, one each on chromosomes 16 and 21, conferred increased disease risk within established CD loci. We performed exome sequencing of 55 Ashkenazi Jewish individuals and follow-up genotyping focused on variants in these two regions. We observed Ashkenazi Jewish-specific nominal association at R755C in TRPM2 on chromosome 21. Within the chromosome 16 region, R642S of HEATR3 and rs9922362 of BRD7 showed genome-wide significance. Expression studies of HEATR3 demonstrated a positive role in NOD2-mediated NF-κB signaling. The BRD7 signal showed conditional dependence with only the downstream rare CD-causal variants in NOD2, but not with the background haplotype; this elaborates NOD2 as a key illustration of synthetic association.

Characterisation of complementary and alternative medicine use and its impact on medication adherence in inflammatory bowel disease.

BACKGROUND: Complementary and alternative medicine (CAM) use among inflammatory bowel disease (IBD) patients is common. We characterised CAM utilisation and assessed its impact on medical adherence in the IBD population. AIM: To characterise CAM utilisation and assess its impact on medical adherence in the IBD population. METHODS: Inflammatory bowel disease patients recruited from an out-patient clinic at a tertiary centre were asked to complete a questionnaire on CAM utilisation, conventional IBD therapy, demographics and communication with their gastroenterologist. Adherence was measured using the self-reported Morisky scale. Demographics, clinical characteristics and self-reported adherence among CAM and non-CAM users were compared. RESULTS: We recruited prospectively 380 IBD subjects (57% Crohn's disease; 35% ulcerative colitis, and 8% indeterminate colitis). The prevalence of CAM use was 56% and did not significantly vary by type of IBD. The most common reason cited for using CAM was ineffectiveness of conventional IBD therapy (40%). The most popular form of CAM was probiotics (53%). CAM users were younger than non-CAM users at diagnosis (21.2 vs. 26.2, P < 0.0001) and more likely than non-CAM users to have a University-level education or higher (75% vs. 62% P = 0.006). There was no overall difference in adherence between CAM and non-CAM users (Morisky score: 1.0 vs. 0.9, P = 0.26). CONCLUSIONS: The use of complementary and alternative medicine is widely prevalent among IBD patients, and is more frequent among those with experience of adverse effects of conventional medications. From this cross-sectional analysis, complementary and alternative medicine use does not appear to be associated with reduced overall adherence to medical therapy.

Trough serum infliximab: a predictive factor of clinical outcome for infliximab treatment in acute ulcerative colitis.

BACKGROUND AND AIMS: Antibodies to infliximab reduce serum infliximab with loss of clinical benefit, but undetectable trough serum concentrations of infliximab may occur without antibody formation. The relationship between trough serum infliximab and clinical outcomes was evaluated in acute ulcerative colitis. METHODS: In a cohort of 115 patients with ulcerative colitis treated with three-dose induction followed by scheduled maintenance infliximab, rates of clinical remission, colectomy, antibodies to infliximab and trough serum infliximab were determined. RESULTS: Rates of remission were 32% at week 10 and 37% at week 54. Colectomy occurred in 40% of patients, at a median of 5.3 (IQR 1.9-12.1) months. Detectable trough serum infliximab was present in 39% of patients and, among patients with undetectable infliximab, 41% were antibody positive and 20% were antibody negative. For antibody-positive and antibody-negative patients, rates of remission (18% vs 14%), endoscopic improvement (25% vs 35%) and colectomy (52% vs 59%) were not different. A detectable serum infliximab was associated with higher rates of remission (69% vs 15%; p<0.001) and endoscopic improvement (76% vs 28%, p<0.001). An undetectable serum infliximab predicted an increased risk for colectomy (55% vs 7%, OR 9.3; 95% CI 2.9 to 29.9; p<0.001). Concurrent immunosuppression was not associated with clinical outcomes. CONCLUSIONS: For patients with ulcerative colitis treated with infliximab, a detectable trough serum infliximab predicts clinical remission, endoscopic improvement and a lower risk for colectomy. An undetectable trough serum infliximab, irrespective of antibody status, is associated with less favourable outcomes.

Polymorphisms in E-cadherin (CDH1) result in a mis-localised cytoplasmic protein that is associated with Crohn's disease.

BACKGROUND: Patients with Crohn's disease have defects in intestinal epithelial permeability that are inadequately explained by known inflammatory bowel disease (IBD) susceptibility genes. E-cadherin (CDH1) plays a vital role in maintaining the integrity of the intestinal barrier and its cellular localisation is disrupted in patients with Crohn's disease. AIM: To determine if polymorphisms in the CDH1 gene are associated with Crohn's disease and to determine the function associated with these polymorphisms. METHODS: The hypothesis was tested using a candidate gene approach using 20 Tag SNPs derived from the HapMap and Crohn's disease trios. Functional studies were carried out using HapMap cell lines and polarised epithelial cell lines (MDCK-1 and Caco2). RESULTS: Here we show that CDH1 is associated with Crohn's disease in 327 trios (rs10431923 excess transmission of "TT" genotype; p = 0.0020) and is replicated in the Wellcome Trust Case Control Consortium CD data set (TT risk allele; OR 1.2, p = 0.005). Patients with the Crohn's disease risk haplotype (rs12597188, rs10431923 and rs9935563; GTC allelic frequency 21%; p = 0.000016) exhibited increased E-cadherin cytoplasmic accumulation in their intestinal epithelium which may be explained by the presence of a novel truncated form of E-cadherin. Accordingly, expression of this truncated E-cadherin in cultured polarised epithelial cells resulted in abnormal intracellular accumulation and impaired plasma membrane localisation of both E-cadherin and beta-catenin. CONCLUSION: The mis-localisation of E-cadherin and beta-catenin may explain the increased permeability seen in some patients with Crohn's disease. Thus, the polymorphisms identified in CDH1 are important for understanding the pathogenesis of Crohn's disease and point to a defect in barrier defence.

Genetic variants in the region harbouring IL2/IL21 associated with ulcerative colitis.

OBJECTIVES: Genetic susceptibility is known to play a large part in the predisposition to the inflammatory bowel diseases (IBDs) known as Crohn's disease (CD) and ulcerative colitis (UC). The IL2/IL21 locus on 4q27 is known to be a common risk locus for inflammatory disease (shown in coeliac disease, type 1 diabetes, rheumatoid arthritis, systemic lupus erythematosus and psoriasis), while the roles that interleukin 2 (IL2) and IL21 play in the immune response also make them attractive candidates for IBD. The objective of this study was to test for association between the IL2/IL21 locus and the IBDs. METHODS: The four single nucleotide polymorphisms (SNPs) in the IL2/IL21 locus most associated with coeliac disease were genotyped in 1590 subjects with IBD and 929 controls from The Netherlands, and then replicated in a North American cohort (2387 cases and 1266 controls) and an Italian cohort (805 cases and 421 controls), yielding a total of 4782 cases (3194 UC, 1588 CD) and 2616 controls. Allelic association testing and a pooled analysis using a Cochran-Mantel-Haenszel test were performed. RESULTS: All four SNPs were strongly associated with UC in all three cohorts and reached genome-wide significance in the pooled analysis (rs13151961 p = 1.35 x 10(-10), rs13119723 p = 8.60 x 10(-8), rs6840978 p = 3.0 7x 10(-8), rs6822844 p = 2.77 x 10(-9)). A moderate association with CD was also found in the pooled analysis (p value range 0.0016-9.86 x 10(-5)). CONCLUSIONS: A strong association for the IL2/IL21 locus with UC was found, which also confirms it as a general susceptibility locus for inflammatory disease.

Gene-centric association mapping of chromosome 3p implicates MST1 in IBD pathogenesis.

Association mapping and candidate gene studies within inflammatory bowel diseases (IBD) linkage regions, as well as genome-wide association studies in Crohn's disease (CD) have led to the discovery of multiple risk genes, but these explain only a fraction of the genetic susceptibility observed in IBD. We have thus been pursuing a region on chromosome 3p21-22 showing linkage to CD and ulcerative colitis (UC) using a gene-centric association mapping approach. We identified 12 functional candidate genes by searching for literature cocitations with relevant keywords and for gene expression patterns consistent with immune/intestinal function. We then performed an association study composed of a screening phase, where tagging single nucleotide polymorphisms (SNPs) were evaluated in 1,020 IBD patients, and an independent replication phase in 745 IBD patients. These analyses identified and replicated significant association with IBD for four SNPs within a 1.2 Mb linkage disequilibrium region. We then identified a non-synonymous coding variant (rs3197999, R689C) in the macrophage-stimulating 1 (MST1) gene (P-value 3.62 x 10(-6)) that accounts for the association signal, and shows association with both CD and UC. MST1 encodes macrophage-stimulating protein (MSP), a protein regulating the innate immune responses to bacterial ligands. R689C is predicted to interfere with MSP binding to its receptor, suggesting a role for this gene in the pathogenesis of IBD.

MAST3: a novel IBD risk factor that modulates TLR4 signaling.

Inflammatory bowel disease (IBD) is a chronic disorder caused by multiple factors in a genetically susceptible host. Significant advances in the study of genetic susceptibility have highlighted the importance of the innate immune system in this disease. We previously completed a genome-wide linkage study and found a significant locus (IBD6) on chromosome 19p. We were interested in identifying the causal variant in IBD6. We performed a two-stage association mapping study. In stage 1, 1530 single-nucleotide polymorphisms (SNPs) were selected from the HapMap database and genotyped in 761 patients with IBD. Among the SNPs that passed the threshold for replication, 26 were successfully genotyped in 754 additional patients (stage 2). One intronic variant, rs273506, located in the microtubule-associated serine/threonine-protein kinase gene-3 (MAST3), was found to be associated in both stages (pooled P=1.8 x 10(-4)). We identified four MAST3 coding variants, including a non-synonymous SNP rs8108738, correlated to rs273506 and associated with IBD. To test whether MAST3 was expressed in cells of interest, we performed expression assays, which showed abundant expression of MAST3 in antigen-presenting cells and in lymphocytes. The knockdown of MAST3 specifically decreased Toll-like receptor-4-dependent NF-kappaB activity. Our findings are additional proofs of the pivotal role played by modulators of NF-kappaB activity in IBD pathogenesis.

An SNP linkage scan identifies significant Crohn's disease loci on chromosomes 13q13.3 and, in Jewish families, on 1p35.2 and 3q29.

Inflammatory bowel disease (IBD) is a complex genetic disorder of two major phenotypes, Crohn's disease (CD) and ulcerative colitis (UC), with increased risk in Ashkenazi Jews. Twelve genome-wide linkage screens have identified multiple loci, but these screens have been of modest size and have used low-density microsatellite markers. We, therefore, performed a high-density single-nucleotide polymorphism (SNP) genome-wide linkage study of 993 IBD multiply affected pedigrees (25% Jewish ancestry) that contained 1709 IBD-affected relative pairs, including 919 CD-CD pairs and 312 UC-UC pairs. We identified a significant novel CD locus on chromosome 13p13.3 (peak logarithm of the odds (LOD) score=3.98) in all pedigrees, significant linkage evidence on chromosomes 1p35.1 (peak LOD score=3.5) and 3q29 (peak LOD score=3.19) in Jewish CD pedigrees, and suggestive loci for Jewish IBD on chromosome 10q22 (peak LOD score=2.57) and Jewish UC on chromosome 2q24 (peak LOD score=2.69). Nominal or greater linkage evidence was present for most previously designated IBD loci (IBD1-9), notably, IBD1 for CD families at chromosome 16q12.1 (peak LOD score=4.86) and IBD6 in non-Jewish UC families at chromosome 19p12 (peak LOD score=2.67). This study demonstrates the ability of high information content adequately powered SNP genome-wide linkage studies to identify loci not observed in multiple microsatellite-based studies in smaller cohorts.

The impact of ulcerative colitis is greater in unmarried and young patients.

GOALS: To determine whether the perceived impact of ulcerative colitis (UC) on activities of living (illness intrusiveness) is greater for people who are not living in a married or common-law relationship. BACKGROUND: In general, social and occupational achievement is not greatly impaired by UC, yet patients, especially young adults, often have interpersonal concerns. METHODS: One hundred fifty-five outpatients with UC were assessed for disease activity, and completed self-reports of marital status, income, social support and illness intrusiveness. RESULTS: Fifty-one patients (32.9%) were single, separated or divorced, and 104 patients (67.1%) were married or in common-law relationships. Compared with those who were married or in common-law relationships, single or separated patients were younger, had a lower household income, had lived with UC for fewer years and were less satisfied with social support. Among 135 patients in remission, marital status was significantly associated with illness intrusiveness, controlling for age, income and perceived social support (F=5.73; P=0.02). Low social support (F=4.94; P=0.03) and younger age (F=7.24; P=0.008) were independently associated with illness intrusiveness. Single patients in remission reported illness intrusiveness of similar severity to that reported by patients with active disease. CONCLUSIONS: The perceived impact of UC on the lives of patients is greater in those who are not married or living in common-law relationships. Youth, single status and lower social support commonly coexist, and exert additive effects on the functional impact of UC. Resources to improve social support should be directed toward this group of patients.

The role of the Toll receptor pathway in susceptibility to inflammatory bowel diseases.

The intestinal flora has long been thought to play a role either in initiating or in exacerbating the inflammatory bowel diseases (IBD). Host defenses, such as those mediated by the Toll-like receptors (TLR), are critical to the host/pathogen interaction and have been implicated in IBD pathophysiology. To explore the association of genetic variation in TLR pathways with susceptibility to IBD, we performed a replication study and pooled analyses of the putative IBD risk alleles in NFKB1 and TLR4, and we performed a haplotype-based screen for association to IBD in the TLR genes and a selection of their adaptor and signaling molecules. Our genotyping of 1539 cases of IBD and pooled analysis of 4805 cases of IBD validates the published association of a TLR4 allele with risk of IBD (odds ratio (OR): 1.30, 95% confidence interval (CI): 1.15-1.48; P=0.00017) and Crohn's disease (OR: 1.33, 95% CI: 1.16-1.54; P=0.000035) but not ulcerative colitis. We also describe novel suggestive evidence that TIRAP (OR: 1.16, 95% CI: 1.04-1.30; P=0.007) has a modest effect on risk of IBD. Our analysis, therefore, offers additional evidence that the TLR4 pathway - in this case, TLR4 and its signaling molecule TIRAP - plays a role in susceptibility to IBD.

The Montreal classification of inflammatory bowel disease: controversies, consensus, and implications.

In recent years, investigators have readdressed the complex issues involved in the classification of inflammatory bowel diseases. In 2003, a Working Party of investigators with an interest in the issues involved in disease subclassification was formed with the aim of summarising recent developments in disease classification and establishing an integrated clinical, molecular, and serological classification of inflammatory bowel disease. The results of the Working Party were reported at the 2005 Montreal World Congress of Gastroenterology. Here we highlight the key issues that have emerged from discussions of the Montreal Working Party and the relevance to clinical practice and research activities.

Diagnostic misclassification reduces the ability to detect linkage in inflammatory bowel disease genetic studies.

BACKGROUND: Linkage data have now identified several inflammatory bowel disease (IBD) susceptibility loci but these data have not been consistently replicated in independent studies. One potential explanation for this is the possibility that patients enrolled in such studies may have been erroneously classified with respect to their diagnosis. AIMS: To determine the rate and type of misclassification in a large population of individuals referred for participation in an IBD genetics study and to examine the effect of diagnostic misclassification on the power to detect linkage. METHODS: The medical records of 1096 patients entered into an IBD genetics programme were reviewed using standardised diagnostic criteria. The original patient reported diagnoses were changed, if necessary, based on review, and the reasons for the change in diagnosis were recorded. To evaluate the effect of misclassification on linkage results, simulations were created with Gensim and analysed using Genehunter to evaluate a model for IBD inheritance. RESULTS: Sixty eight of 1096 (6.2%) individuals had a change in diagnosis from that originally reported. The majority of changes were patients with either Crohn's disease or ulcerative colitis who were determined not to have IBD at all. The principal reasons for changes to the original diagnosis were discordance between the patients' subjective reports of diagnosis and actual clinical history, endoscopic, or pathological results; a change in disease pattern over time; and insufficient information available to confirm the original diagnosis. A 10% misclassification rate resulted in 28.4% and 40.2% loss of power to detect a true linkage when using a statistical model for a presumed IBD locus with lambda(s) values of 1.8 and 1.3, respectively. CONCLUSIONS: Diagnostic misclassification occurs in patients enrolled in IBD genetic studies and frequently involves assigning the diagnosis of IBD to non-affected individuals. Even low rates of diagnostic misclassification can lead to significant loss of power to detect a true linkage, particularly for loci with modest effects as are likely to be found in IBD.