Disease location, anti-Saccharomyces cerevisiae antibody, and NOD2/CARD15 genotype influence the progression of disease behavior in Crohn's disease

Personalized Treatment for Crohn's Disease: Current Approaches and Future Directions

Crohn's disease is a complex, relapsing and remitting inflammatory disorder of the gastrointestinal tract with a variable disease course. While the treatment options for Crohn's disease have dramatically increased over the past two decades, predicting individual patient response to treatment remains a challenge. As a result, patients often cycle through multiple different therapies before finding an effective treatment which can lead to disease complications, increased costs, and decreased quality of life. Recently, there has been increased emphasis on personalized medicine in Crohn's disease to identify individual patients who require early advanced therapy to prevent complications of their disease. In this review, we summarize our current approach to management of Crohn's disease by identifying risk factors for severe or disabling disease and tailoring individual treatments to patient-specific goals. Lastly, we outline our knowledge gaps in implementing personalized Crohn's disease treatment and describe the future directions in precision medicine.

Evaluation of a downstaging, bidirectional version of the Montreal classification of Crohn's disease: Analysis of 5-year follow-up data from the prospective BioCrohn study

OBJECTIVE

Under the assumption of irreversibility, the Montreal classification provides a unidirectional assessment of the complications and behaviour of Crohn's disease (CD) that does not allow for downstaging. We examined the use of a bidirectional Montreal classification system that can capture disease regression.

DESIGN

From the BioCrohn Registry, an inception cohort of patients with CD for ≤12 months duration was defined and followed up for 5-years. Cumulative probabilities for developing complications were estimated using the Kaplan-Meier method. Potential associations of explanatory variables with disease progression were estimated with Cox regression.

RESULTS

Among 393 incident CD patients (of whom 255 completed the entire follow-up), the 5-year cumulative probability of developing complications was 41.5% (15.6% and 25.9% for stricturing and penetrating complications respectively). Perianal disease (hazard ratio [95% confidence interval]: 8.45 [4.74-15.07]) and surgical resection of the intestine (2.71 [1.50-4.92]) in the very early phase of the disease were associated with a higher risk of developing a penetrating complication within the 5-year follow-up. The use of a bidirectional Montreal classification system which can account for disease regression demonstrated that 90% of patients exhibited inflammatory disease behaviour at 5 years, in contrast to 58%, if the hierarchical, unidirectional Montreal classification system was used.

CONCLUSION

An additional bidirectional disease behaviour assessment capturing reversed or fully controlled complications may provide a more realistic appraisal of the complexity and unmet needs of patients treated with advanced therapies.

Newly Diagnosed Crohn's Disease Patients in India and Israel Display Distinct Presentations and Serological Markers: Insights from Prospective Cohorts

Background: Crohn’s disease (CD) incidence is rising in India. However, features of newly diagnosed patients with CD in this population are largely unknown. The Indo-Israeli IBD GastroEnterology paRtnership (TiiiGER) aimed to investigate differences in presentation among patients with newly diagnosed CD in India and Israel, and to explore phenotype−serotype correlations. Methods: A prospective observational cohort study of consecutive adults (>18 years) conducted in two large referral centers in India and Israel (2014−2018). Clinical data, an antiglycan serological panel, and 20 CD-associated genetic variants were analyzed. Outcomes: complicated phenotype at diagnosis and early complicated course (hospitalizations/surgeries) within 2 years of diagnosis. Results: We included 260 patients (104, Indian (65.4%, male; age, 37.8); 156 Israeli (49.4%, male; 31.8, age)). Median lag time from symptoms onset to diagnosis was 10.5 (IQR 3−38) vs. 3 (IQR 1−8) months in Indian vs. Israeli patients (p < 0.001). Complicated phenotype at diagnosis was observed in 48% of Indian and 30% of Israeli patients (p = 0.003). Complicated phenotype was associated with higher anti-Saccharomyces cerevisiae antibody (ASCA) seropositivity rate among Israeli patients (p < 0.001), but not among Indian patients. Antiglycan serology did not correlate with the tested genetic variants. Early complicated course occurred in 28 (18%) Israeli and 13 (12.5%) Indian patients. The time from diagnosis to complication was comparable (log rank p = 0.152). Antiglycan serology did not correlate with a complicated early course in either cohort. Conclusions: There are significant differences in patients presenting with newly diagnosed CD in India and Israel, including phenotype and distinct biomarkers at diagnosis. These differences suggest different genetic and environmental disease modifiers.

Biomarkers for the Prediction and Diagnosis of Fibrostenosing Crohn's Disease: A Systematic Review

BACKGROUND AND AIMS

Intestinal strictures are a common complication of Crohn's disease (CD). Biomarkers of intestinal strictures would assist in their prediction, diagnosis, and monitoring. Herein we provide a comprehensive systematic review of studies assessing biomarkers that may predict or diagnose CD-associated strictures.

METHODS

We performed a systematic review of PubMed, EMBASE, ISI Web of Science, Cochrane Library, and Scopus to identify citations pertaining to biomarkers of intestinal fibrosis through July 6, 2020, that used a reference standard of full-thickness histopathology or cross-sectional imaging or endoscopy. Studies were categorized based on the type of biomarker they evaluated (serum, genetic, histopathologic, or fecal).

RESULTS

Thirty-five distinct biomarkers from 3 major groups were identified: serum (20 markers), genetic (9 markers), and histopathology (6 markers). Promising markers include cartilage oligomeric matrix protein, hepatocyte growth factor activator, and lower levels of microRNA-19-3p (area under the curves were 0.805, 0.738, and 0.67, respectively), and multiple anti-flagellin antibodies (A4-Fla2 [odds ratio, 3.41], anti Fla-X [odds ratio, 2.95], and anti-CBir1 [multiple]). Substantial heterogeneity was observed and none of the markers had undergone formal validation. Specific limitations to acceptance of these markers included failure to use a standardized definition of stricturing disease, lack of specificity, and insufficient relevance to the pathogenesis of intestinal strictures or incomplete knowledge regarding their operating properties.

CONCLUSIONS

There is a lack of well-defined studies on biomarkers of intestinal stricture. Development of reliable and accurate biomarkers of stricture is a research priority. Biomarkers can support the clinical management of CD patients and aid in the stratification and monitoring of patients during clinical trials of future antifibrotic drug candidates.

Increasing experience with the LIFT procedure in Crohn's disease patients with complex anal fistula

BACKGROUND

Surgical management of anal fistulas in Crohn's disease (CD) is associated with high failure rates, and treatment options are limited due to ongoing proctitis, multiple tracts, and concern for incontinence and non-healing wounds. The aim of this study was to investigate the healing rate of ligation of the inters-sphincteric fistula tract (LIFT) for anal fistulas in Crohn's disease and identify prognostic factors for healing.

METHODS

This prospective analysis compared long-term healing rates of CD patients undergoing LIFT for anal fistulas. Consecutive patients with CD who underwent LIFT procedure at our institution, in the period from March 2012 to September 2019 were included. The main outcome was anal fistula healing rate.

RESULTS

The study cohort of 46 patients (mean age of 34.2 ± 13.0 years, 18 (40%) males). After a mean follow-up time of 33 ± 28 months, fistula healing was seen in 30 (65%) patients. A total of 8 patients were noted to have inter-sphincteric recurrence and 8 patients had trans-sphincteric recurrence. Smoking at the time of surgery was significantly associated with LIFT failure (HR 3.18, 95% CI 1.18-8.61, p = 0.02). Other factors, such as age, sex, race, disease duration and location, type of fistula history of proctitis, preoperatively use of biologics or a seton, and previous repair attempts, did not appear to influence LIFT healing. Although not statistically significant, there was a trend toward increase in failure among patients with active proctitis at the time of surgery (HR 1.97, 95% CI 0.71-5.42, p = 0.19).

CONCLUSION

Our increasing experience with LIFT for anal fistula in CD demonstrates a higher rate of healing (65%) than previously reported (48%). Smoking appears to negatively influence healing of LIFT in CD.

Prognostic biomarkers to identify patients likely to develop severe Crohn's disease: a systematic review

BACKGROUND

Identification of biomarkers that predict severe Crohn's disease is an urgent unmet research need, but existing research is piecemeal and haphazard.

OBJECTIVE

To identify biomarkers that are potentially able to predict the development of subsequent severe Crohn's disease.

DESIGN

This was a prognostic systematic review with meta-analysis reserved for those potential predictors with sufficient existing research (defined as five or more primary studies).

DATA SOURCES

PubMed and EMBASE searched from inception to 1 January 2016, updated to 1 January 2018.

REVIEW METHODS

Eligible studies were studies that compared biomarkers in patients who did or did not subsequently develop severe Crohn's disease. We excluded biomarkers that had insufficient research evidence. A clinician and two statisticians independently extracted data relating to predictors, severe disease definitions, event numbers and outcomes, including odds/hazard ratios. We assessed risk of bias. We searched for associations with subsequent severe disease rather than precise estimates of strength. A random-effects meta-analysis was performed separately for odds ratios.

RESULTS

In total, 29,950 abstracts yielded just 71 individual studies, reporting 56 non-overlapping cohorts. Five clinical biomarkers (Montreal behaviour, age, disease duration, disease location and smoking), two serological biomarkers (anti-Saccharomyces cerevisiae antibodies and anti-flagellin antibodies) and one genetic biomarker (nucleotide-binding oligomerisation domain-containing protein 2) displayed statistically significant prognostic potential. Overall, the strongest association with subsequent severe disease was identified for Montreal B2 and B3 categories (odds ratio 4.09 and 6.25, respectively).

LIMITATIONS

Definitions of severe disease varied widely, and some studies confounded diagnosis and prognosis. Risk of bias was rated as 'high' in 92% of studies overall. Some biomarkers that are used regularly in daily practice, for example C-reactive protein, were studied too infrequently for meta-analysis.

CONCLUSIONS

Research for individual biomarkers to predict severe Crohn's disease is scant, heterogeneous and at a high risk of bias. Despite a large amount of potential research, we encountered relatively few biomarkers with data sufficient for meta-analysis, identifying only eight biomarkers with potential predictive capability.

FUTURE WORK

We will use existing data sets to develop and then validate a predictive model based on the potential predictors identified by this systematic review. Contingent on the outcome of that research, a prospective external validation may prove clinically desirable.

STUDY REGISTRATION

This study is registered as PROSPERO CRD42016029363.

FUNDING

This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 25, No. 45. See the NIHR Journals Library website for further project information.

A watchful waiting approach for newly diagnosed Crohn's disease patients with an inflammatory phenotype

BACKGROUND

An early treat-to-target approach in Crohn's disease (CD) patients is recommended to avoid complications. However, CD may not always progress despite lack of treatment, thus exposing some patients to unnecessary side effects. We aimed to examine whether newly diagnosed CD patients with an inflammatory phenotype can benefit from a watchful waiting approach.

METHODS

This retrospective cohort study followed CD patients with an inflammatory phenotype who were diagnosed between 2010 and 2015 and followed for at least 1 year. A watchful waiting approach was defined as maintenance therapy with 5-ASA medication only or no treatment during the first year of diagnosis or longer. Disease complications were defined as need for surgery or change in disease phenotype.

RESULTS

Eighty-six patients were included and followed-up for 57.0 ± 29.0 months. Thirty-seven patients were managed with a watchful waiting approach and 49 with an early therapeutic intervention. The majority of patients (83.8%) in the watchful waiting group did not develop disease complications. In this group, there was no difference in clinical disease severity (stools per day, 2.7 ± 1.7 vs 3.3 ± 1.0, P = 0.39; abdominal pain, 74.2 vs 50.0%, P = 0.24) between those who did not develop complications and those who did. Smoking was associated with a complicated course (multivariate analysis: OR = 1.98, 95% CI 1.06-3.71, P = 0.03).

CONCLUSIONS

A watchful waiting approach of newly diagnosed CD patients with an inflammatory phenotype may be a feasible option, with low long-term complication rate specifically in nonsmoking patients.

Intestinal stenosis in Crohn's disease shows a generalized upregulation of genes involved in collagen metabolism and recognition that could serve as novel anti-fibrotic drug targets

BACKGROUND AND AIMS

Crohn's disease (CD) can be complicated by intestinal fibrosis. Pharmacological therapies against intestinal fibrosis are not available. The aim of this study was to determine whether pathways involved in collagen metabolism are upregulated in intestinal fibrosis, and to discuss which drugs might be suitable to inhibit excessive extracellular matrix formation targeting these pathways.

METHODS

Human fibrotic and non-fibrotic terminal ileum was obtained from patients with CD undergoing ileocecal resection due to stenosis. Genes involved in collagen metabolism were analyzed using a microfluidic low-density TaqMan array. A literature search was performed to find potential anti-fibrotic drugs that target proteins/enzymes involved in collagen synthesis, its degradation and its recognition.

RESULTS

mRNA expression of collagen type I (COL1A1, 0.76 ± 0.28 versus 37.82 ± 49.85, p = 0.02) and III (COL3A1, 2.01 ± 2.61 versus 68.65 ± 84.07, p = 0.02) was increased in fibrotic CD compared with non-fibrotic CD. mRNA expression of proteins involved in both intra- and extracellular post-translational modification of collagens (prolyl- and lysyl hydroxylases, lysyl oxidases, chaperones), collagen-degrading enzymes (MMPs and cathepsin-K), and collagen receptors were upregulated in the fibrosis-affected part. A literature search on the upregulated genes revealed several potential anti-fibrotic drugs.

CONCLUSION

Expression of genes involved in collagen metabolism in intestinal fibrosis affected terminal ileum of patients with CD reveals a plethora of drug targets. Inhibition of post-translational modification and altering collagen metabolism might attenuate fibrosis formation in the intestine in CD. Which compound has the highest potential depends on a combination anti-fibrotic efficacy and safety, especially since some of the enzymes play key roles in the physiology of collagen.

Risk factors associated with progression to intestinal complications of Crohn disease

BACKGROUND

Crohn disease is a chronic bowel disease that causes serious complications. Prevalence of Crohn disease is increasing. Studies have shown that the behavior of the disease is not stable and severe complications secondary to behavior change over time have been shown. In this study, we aimed to evaluate the prognostic risk factors associated with phenotypic change in Crohn disease in a Turkish patient cohort.

METHODS

Patients followed up from March 1986 to August 2011 were evaluated for demographic and clinical characteristics to determine possible risk factors and initial clinical phenotype of the disease based on the Montreal classification. The cumulative probabilities of developing stricturing or penetrating intestinal complications were estimated using the Kaplan-Meier analysis. Univariate and multivariate Cox-proportional hazard models were used to assess associations between baseline clinical characteristics and intestinal complications.

RESULTS

Three hundred and thirty patients (mean age, 30.6 ± 11.1 years; 148 female) were included in the study. Mean follow-up duration was 7.4 ± 5.3 years (range: 1.0-25.0 years). At baseline 273 patients had inflammatory-type disease, 57 patients experienced stricturing/penetrating intestinal complications before or at the time of diagnosis. The cumulative probability of developing complicated disease was 37.4% at 5 years, 54.3% at 10 years, 78.8% at 25 years. Independent predictors associated with progression to intestinal complications were current smoking, perianal disease, extra-intestinal manifestations, and location of disease.

CONCLUSIONS

Location of disease is the most powerful indicator for the development of stenosis and penetrating complications in inflammatory-type disease. Patients with ileal involvement should be considered for more aggressive immunosuppressive therapy.

Effects of Perianal Involvement on Clinical Outcomes in Crohn's Disease over 10 Years

Background/Aims

There was the assumption that Crohn's disease (CD) patients with perianal lesions might have different clinical courses compared to those without. However, quantifiable data comparing the long-term outcomes between the two groups are scarce.

Methods

We retrospectively reviewed 221 consecutive patients newly diagnosed with CD and registered at the IBD clinic of Severance Hospital, in Seoul, Korea, between January 1990 and October 2005. We compared patients with perianal CD (PCD) and non-perianal CD (NPCD) in terms of clinical outcomes over 10 years.

Results

PCD progressed more frequently from inflammatory to complicated behavior than NPCD. Moreover, corticosteroids were prescribed in 102 patients with PCD and only 57 with NPCD (82.9% vs 58.2%, p＜0.001), immunosuppressants in 89 and 42 (72.4% vs 42.9%, p＜0.001), and anti-tumor necrosis factor α (TNF-α) in 37 and 12 (30.1% vs 12.2%, p=0.002). Cumulative hospitalization rates were 82.1% in PCD and 72.4% in NPCD (p=0.086), and surgical intervention rates were 39.8% and 51.0%, respectively (p=0.097).

Conclusions

Patients with PCD were more likely than those with NPCD to be administered corticosteroids, immunosuppressants, and anti-TNF-α. However, there is no significant difference in the cumulative rates of surgical interventions or hospitalizations.

Association of clinical and inflammatory markers with small bowel capsule endoscopy findings in Crohn's disease

BACKGROUND

Mucosal healing is an established treatment endpoint in Crohn's disease (CD). Still, clinical indices and inflammatory markers are used widely in CD surveillance.

AIM

The aim of this study was to investigate the diagnostic performance as well as the relationship of C-reactive protein (CRP) and Crohn's Disease Activity Index (CDAI) with small bowel capsule endoscopy's (SBCE) inflammation scoring index, the Lewis Score (LS).

PATIENTS AND METHODS

CDAI, CRP, and SBCE findings of 30 CD patients with isolated small bowel disease were retrieved from our academic institution patient records and were analyzed statistically.

RESULTS

SBCE showed significant mucosal inflammation [mean (SD) LS: 1599 (1380)], in nine (60.0%) of 15 patients who were in both clinical and biochemical remission. CDAI and CRP showed a weak and moderate correlation with LS (r=0.317, P=0.088 and r=0.516, P=0.004, respectively). The diagnostic performance of CDAI and CRP in predicting mucosal inflammation was as follows: sensitivity 23.8 and 52.4%; specificity 100 and 66.7%; positive predictive value 100 and 78.6%; and negative predictive value 36.0 and 37.5%. The area under the curve toward endoscopic activity prediction was 0.70 and 0.69, respectively.

CONCLUSION

Both CDAI and CRP underestimated endoscopic activity as expressed by the LS in a significant proportion of patients with quiescent disease.

Misbalance in type III collagen formation/degradation as a novel serological biomarker for penetrating (Montreal B3) Crohn's disease

BACKGROUND

Misbalances in extracellular matrix turnover are key factors in the development of stricturing (Montreal B2) and penetrating (Montreal B3) Crohn's disease.

AIM

To determine whether serological markers for collagen formation and degradation could serve as biomarkers for complications of Crohn's disease.

METHODS

Serum biomarkers for type I, III, V and VI collagen formation (P1NP, Pro-C3, Pro-C5, Pro-C6) and matrix metalloproteinase mediated degradation (C1M, C3M, C5M and C6M) were measured in a retrospective, single centre cohort of 112 patients with Crohn's disease in the terminal ileum (nonstricturing/nonpenetrating: n=40, stricturing: n=55, penetrating: n=17) and 24 healthy controls. Active inflammation was defined as CRP >5 mg/L.

RESULTS

C3M and Pro-C5 levels were higher in penetrating vs nonpenetrating/nonstricturing and stricturing disease (33.6±5 vs 25.8±2.2 [P=.004] and 27.2±2.3 [P=.018] nmol/L C3M, 1262.7±259.4 vs 902.9±109.9 [P=.005] and 953.0±106.4 [P=.015] nmol/L Pro-C5). C1M (71.2±26.1 vs 46.2±6.2 nmol/L [P<.001]), C3M (31.6±3.9 vs 26.1±1.6 nmol/L [P=.002] and Pro-C5 levels (1171.7±171.5 vs 909.6±80.4 nmol/L [P=.002]) were higher in patients with active inflammation vs without active inflammation. Pro-C3/C3M-ratios were best to differentiate between penetrating vs nonstricturing/nonpenetrating and stricturing disease with area under the curves of 0.815±0.109 (P<.001) and 0.746±0.114 (P=.002) respectively.

CONCLUSIONS

Serological biomarkers show that penetrating Crohn's disease is characterised by increased matrix metalloproteinase-9 degraded type III collagen and formation of type V collagen. Active inflammation in Crohn's disease is characterised by increased formation of type V collagen and increased matrix metalloproteinase mediated breakdown of type I, III collagen. Pro-C3/C3M ratios are superior in differentiating between penetrating Crohn's disease vs inflammatory and stricturing Crohn's disease.

Bowel Thickening in Crohn's Disease: Fibrosis or Inflammation? Diagnostic Ultrasound Imaging Tools

The high frequency of intestinal strictures in patients with Crohn's disease and the different treatment approaches specific for each type of stenosis make the differentiation between fibrotic and inflammatory strictures crucial in management of the disease. However, there is no standardized approach to evaluate and discriminate intestinal strictures, and until now, there was no established cross-sectional imaging modality to detect fibrosis. New techniques, such as contrast-enhanced ultrasound and sonoelastography allow the assessment of vascularization and mechanical properties of stenotic bowel tissue, respectively. These techniques have shown great potential to characterize strictures in Crohn's disease. The aim of this review is to sum up the current knowledge on bowel ultrasound tools to discriminate inflammatory from fibrotic stenosis in Crohn's disease considering the most recent published studies in the field.

Gut Bacterial DNA Translocation is an Independent Risk Factor of Flare at Short Term in Patients With Crohn's Disease

OBJECTIVES

We aimed at evaluating bacterial DNA (bactDNA) presence in blood of Crohn's disease (CD) patients in remission as an independent risk factor of flare at 6 months.

METHODS

This is a prospective, multicenter study on CD patients with Crohn's disease activity index (CDAI)<150. The primary end point was time-to-relapse as evaluated by CDAI>150 in the following 6 months. BactDNA in blood, the nucleotide-binding oligomerization domain containing 2 (NOD2) genotype, and serum cytokine levels were determined at baseline.

RESULTS

A total of 288 patients were included. BactDNA was detected in 98 patients (34.0%). A variant-NOD2 genotype was identified in 114 patients (39.6%). Forty patients (14%) relapsed during follow-up. Multivariate survival analysis identified bactDNA as an independent risk factor of flare (hazard ratio (HR) 8.75 (4.02-19.06) 95% confidence interval (CI)). Hospitalization, surgery, switch of treatment, initiation and escalation of anti-tumor necrosis factor (TNF) therapy, steroids initiation, and increased fecal calprotectin levels at 6 months were associated with bactDNA at baseline. A logistic regression analysis showed bactDNA as an independent and significant predictive factor of hospitalization (odds ratio (OR) 11.9 (3.4-42.3); P<0.001), steroids startup (OR 8.5 (2.7-27.1); P<0.001), and switch of treatment (OR 3.5 (1.6-7.7); P=0.002) at 6 months. No relationship was observed between bactDNA and mucosal lesions in patients with colonoscopy at admission. Serum pro-inflammatory cytokines were significantly increased in patients with bactDNA or a variant-NOD2 genotype. The combination of both factors induced decreased anti-TNF-α levels and a higher percentage of patients on intensified anti-TNF therapy.

CONCLUSIONS

BactDNA is an independent risk factor of relapse at 6 months in CD patients. BactDNA is also independently associated with an increased risk of hospitalization, switch of treatment, and steroids initiation.

Early Course of Inflammatory Bowel Disease in a Population-Based Inception Cohort Study From 8 Countries in Asia and Australia

BACKGROUND & AIMS

The incidence of inflammatory bowel disease (IBD) is increasing in Asia, but little is known about disease progression in this region. The Asia-Pacific Crohn's and Colitis Epidemiology Study was initiated in 2011, enrolling subjects from 8 countries in Asia (China, Hong Kong, Indonesia, Sri Lanka, Macau, Malaysia, Singapore, and Thailand) and Australia. We present data from this ongoing study.

METHODS

We collected data on 413 patients diagnosed with IBD (222 with ulcerative colitis [UC], 181 with Crohn's disease [CD], 10 with IBD unclassified; median age, 37 y) from 2011 through 2013. We analyzed the disease course and severity and mortality. Risks for medical and surgical therapies were assessed using Kaplan-Meier analysis.

RESULTS

The cumulative probability that CD would change from inflammatory to stricturing or penetrating disease was 19.6%. The cumulative probabilities for use of immunosuppressants or anti-tumor necrosis factor agents were 58.9% and 12.0% for patients with CD, and 12.7% and 0.9% for patients with UC, respectively. Perianal CD was associated with an increased risk of anti-tumor necrosis factor therapy within 1 year of its diagnosis (hazard ratio, 2.97; 95% confidence interval, 1.09-8.09). The cumulative probabilities for surgery 1 year after diagnosis were 9.1% for patients with CD and 0.9% for patients with UC. Patients with CD and penetrating disease had a 7-fold increase for risk of surgery, compared with patients with inflammatory disease (hazard ratio, 7.67; 95% confidence interval, 3.93-14.96). The overall mortality for patients with IBD was 0.7%.

CONCLUSIONS

In a prospective population-based study, we found that the early course of disease in patients with IBD in Asia was comparable with that of the West. Patients with CD frequently progress to complicated disease and have accelerated use of immunosuppressants. Few patients with early stage UC undergo surgery in Asia. Increasing our understanding of IBD progression in different populations can help optimize therapy and improve outcomes.

The Influence of Second-Hand Cigarette Smoke Exposure during Childhood and Active Cigarette Smoking on Crohn's Disease Phenotype Defined by the Montreal Classification Scheme in a Western Cape Population, South Africa

Background

Smoking may worsen the disease outcomes in patients with Crohn’s disease (CD), however the effect of exposure to second-hand cigarette smoke during childhood is unclear. In South Africa, no such literature exists. The aim of this study was to investigate whether disease phenotype, at time of diagnosis of CD, was associated with exposure to second-hand cigarette during childhood and active cigarette smoking habits.

Methods

A cross sectional examination of all consecutive CD patients seen during the period September 2011-January 2013 at 2 large inflammatory bowel disease centers in the Western Cape, South Africa was performed. Data were collected via review of patient case notes, interviewer-administered questionnaire and clinical examination by the attending gastroenterologist. Disease phenotype (behavior and location) was evaluated at time of diagnosis, according to the Montreal Classification scheme. In addition, disease behavior was stratified as ‘complicated’ or ‘uncomplicated’, using predefined definitions. Passive cigarette smoke exposure was evaluated during 3 age intervals: 0–5, 6–10, and 11–18 years.

Results

One hundred and ninety four CD patients were identified. Cigarette smoking during the 6 months prior to, or at time of diagnosis was significantly associated with ileo-colonic (L3) disease (RRR = 3.63; 95%CI, 1.32–9.98, p = 0.012) and ileal (L1) disease (RRR = 3.54; 95%CI, 1.06–11.83, p = 0.040) compared with colonic disease. In smokers, childhood passive cigarette smoke exposure during the 0–5 years age interval was significantly associated with ileo-colonic CD location (RRR = 21.3; 95%CI, 1.16–391.55, p = 0.040). No significant association between smoking habits and disease behavior at diagnosis, whether defined by the Montreal scheme, or stratified as ‘complicated’ vs ‘uncomplicated’, was observed.

Conclusion

Smoking habits were associated with ileo-colonic (L3) and ileal (L1) disease at time of diagnosis in a South African cohort.

Differential response to microbial antigens by age of diagnosis in patients with Crohn's disease

PURPOSE

Fifteen percent of incident Crohn's disease (CD) cases are diagnosed at older ages and demonstrate colonic location and inflammatory behavior. Serologic responses to gut microbial antigens are associated with specific phenotypes, and may differ by age at diagnosis. Our aim was to identify an association between age at diagnosis of CD and responses to gut microbial antigens.

PATIENTS AND METHODS

Levels of anti-Saccharomyces cerevisiae antibodies (ASCA) immunoglobulins A and G (IgA and IgG), antibodies to Escherichia coli outer membrane porin-C (anti-Omp-C), antibodies to clostridial flagellin (anti-CBir-1), and perinuclear anti-neutrophil cytoplasmic antibodies (p-ANCA) were compared in patients by age in three diagnosis groups: patients diagnosed at ages of <40, ≥40-59, and ≥60 years. For each antigen, patients with antibody levels in the first, second, third, and fourth quartile were assigned a score of 1, 2, 3, or 4, respectively. Individual scores were added to create a quartile sum score representing cumulative quantitative immune response.

RESULTS

Eighteen, 17, and 12 patients were diagnosed at ages <40, 40-59, and ≥60 years, respectively. The majority (71%) had ileocolonic disease in the youngest group, compared to 36% in the oldest group (P=0.001). Mean ASCA IgA and IgG titers were increased in the youngest age group compared to the older groups (P=0.19 and P=0.13, respectively). Mean quartile sum scores for antibody levels were 7.2±2.8 in those patients diagnosed at ages <40 years, 4.9±2.9 in the 40-59-year-old age group, and 5.6±2.6 in the ≥60-year-old age group (P=0.06).

CONCLUSION

A trend toward decreased cumulative immune responses to CD-associated gut antigens was observed in CD patients diagnosed at older ages compared to younger patients. Host responses to microbial antigens may be less important in older onset IBD and may contribute to the distinct phenotype in this group.

Opioid use is associated with decreased quality of life in patients with Crohn's disease

BACKGROUND/AIMS

Quality of life is an important consideration in the management of patients with Crohn's disease. Previous studies suggest that Crohn's disease patients using opioids may have decreased quality of life and increased risk of mortality. Our aim was to determine the association between health-related quality of life (HRQoL) and opioid use in patients with Crohn's disease while controlling for disease severity.

PATIENTS AND METHODS

We conducted a cross-sectional study recruiting Crohn's disease patients at our center. Disease activity was measured using the Harvey-Bradshaw Index (HBI), and HRQoL was measured using the Inflammatory Bowel Disease Questionnaire (IBDQ).

RESULTS

We enrolled 38 Crohn's disease patients using opioids and 62 patients not using opioids. Patients using opioids had an increased duration of disease (median 18.5 vs. 9 years, P = 0.005), increased surgeries related to Crohn's disease (median 3 vs. 0, P < 0.001), and increased prednisone use (29% vs. 11.3%, P = 0.03). Patients using opioids had increased disease activity (median HBI score 9.0 vs. 3.0, P < 0.001). Quality of life was lower in patients using opioids (mean IBDQ score 109.3 vs. 162.9, P < 0.001). This finding was significant when controlling for HBI scores, number of previous surgeries, and prednisone use (P = 0.003).

CONCLUSIONS

Opioid use in Crohn's disease patients appears to be associated with disease activity and severity. HRQoL is markedly decreased in patients using opioids and this association is significant even when controlling for variables reflecting disease severity. Our findings suggest that Crohn's disease patients using opioids are likely to be significantly impacted by their disease.

The clinical significance of antimicrobial serologic responses within an Irish Crohn's disease population

INTRODUCTION

A hyper-responsive adaptive immunologic response to a variety of microbial antigens has been described in Crohn's disease (CD) patients and elevated levels of a number of antibodies have been identified in the sera of CD patients. To date, the serological profiles of an Irish CD population have not been characterized.

OBJECTIVES

The aim of this study is to determine the serological profile of Irish patients with CD. Second, we aim to assess the correlation, if any, between serological profile and disease phenotype within this cohort.

METHODS

A total of 179 consecutive adults with CD attending a specialist inflammatory bowel disease clinic at a university hospital were recruited. Blood samples were taken and sera were analysed for the expression of pANCA and Crohn's related antibodies.

RESULTS

pANCA was present in 47/179 (26.3%), anti-OmpC antibodies were present in 49/179 (27.4%), anti-Saccharomyces cervisiae (ASCA) in 64/179 (35.75%), ASCA IgA in 56/179 (31.28%) and ASCA IgG in 37/179 (20.67%), and anti-CBir antibodies in 97/179 (54.18%). The presence of ASCA IgA (P=0.031), ASCA IgG (P=0.007) and anti-CBir antibodies (P=0.003) were all significantly associated with small bowel involvement. Anti-OmpC, ASCA IgA and anti-CBir antibodies' positivity were all associated with complicated disease behaviour, whereas ANCA positivity was associated with inflammatory disease.

CONCLUSION

Our study supports previous findings of an association between serological profiles and disease behaviour and a corresponding association with increased need for surgery. In this genetically homogenous Irish CD study group, the levels of specific antibody responses to commensal gut flora are lower than reported previously in other European and American populations.

Isolated active ileitis: is it a mild subtype of Crohn's disease?

BACKGROUND

Ileal intubation is being increasingly performed at colonoscopy and has in turn lead to an increasingly recognized subgroup of patients-those with mild terminal ileal inflammation, an entity that we have coined isolated active ileitis (IAI). The aims of this study were to define the natural history of IAI and determine if IAI shares a similar genetic and serologic profile with Crohn's disease (CD).

METHODS

Patients with IAI were identified from our institution's histopathology and endoscopy databases. Cases attended for repeat colonoscopy and blood were analyzed for the expression of antineutrophil cytoplasmic antibody, anti-OmpC, anti-Saccharomyces cerevisiae antigen (ASCA) IgA, ASCA IgG, and anti-CBir antibodies and NOD2 genotyping. Age and sex-matched healthy controls, CD, and UC cases were also recruited.

RESULTS

Sixty-three patients with IAI were recruited. There was no significant difference in the prevalence of antibodies between IAI cases and healthy controls for antineutrophil cytoplasmic antibody, OmpC, ASCA IgA, or ASCA IgG. The presence of all 5 antibodies was significantly higher in the CD group than the IAI group, P < 0.05. There were 28.6% of CD cases that carried one or more NOD2 variants, compared to 26.2% of the IAI cohort and 6.1% of healthy controls. Forty-three cases underwent follow-up ileocolonoscopy. Six of 43 cases (14%) had definite CD.

CONCLUSIONS

A majority of IAI cases developed persistent symptoms and terminal ileal abnormalities; however, only 14% developed classical, histological, or radiological features of CD. Although patients with IAI have a low level of seropositivity, similar to healthy controls, they do share an excess of NOD2 mutations with CD cases.

Serum antibodies associated with complex inflammatory bowel disease

BACKGROUND

Antibodies to microbial antigens have been associated with specific diagnoses and phenotypes of inflammatory bowel disease. We evaluated the prevalence of pANCA, IgA and IgG anti-Saccharomyces cerevisiae antibodies, anti-OmpC, and anti-flagellin in a large well-defined population of patients with Crohn's disease (CD) and ulcerative colitis (UC) and analyzed for various clinical outcomes.

METHODS

Samples were collected from 391 patients with CD, 207 patients with UC, and 62 healthy controls. Patients were phenotyped using the Montreal classification. Blinded serological analyses were performed for pANCA, IgA and IgG anti-Saccharomyces cerevisiae antibodies, anti-OmpC, and anti-flagellin.

RESULTS

In CD, increasing quantitative levels for antibodies were associated with a younger age of diagnosis, longer disease duration, increased surgeries, ileocolonic and perianal disease, and internal perforating behavior. In UC, they were associated with colectomy. An increasing number of seropositive antibodies in CD was associated with a younger age at diagnosis, increased disease duration, ileocolonic and perianal disease, internal penetrating and stricturing behavior, and increased surgeries. Multivariate analysis confirmed the association of antimicrobial antibodies with features of complicated CD and UC.

CONCLUSIONS

Increased serological markers are associated with a more aggressive CD phenotype and an increased need for colectomy in UC. This raises the possibility for use of these markers in patients at risk of complex disease.

Does active smoking really influence the course of Crohn's disease? A retrospective observational study

BACKGROUND

Active smoking has been associated with a higher risk of developing Crohn's disease (CD). However, its impact on clinical outcomes has been controversial among studies.

AIMS

To evaluate the influence of active smoking on initial manifestations of CD, the development of disease-related complications, and therapeutic requirements.

METHODS

Patients diagnosed with CD within a ten-year period (1994-2003) were identified. Clinical and therapeutic features until October 2008 or loss of follow-up were recorded. Smoking status was assessed at each major disease-related event (e.g. penetrating and stricturing complications, perianal disease, intestinal resection, introduction of immunomodulators or biological agents).

RESULTS

A total of 259 patients were included in the study with a median follow-up period of 91 months. At diagnosis, 50.5% were active smokers and only 12% of them quit smoking during follow-up, mostly after a major disease-related event occurred. Smoking at diagnosis was not associated with a particular CD presentation. Active smoking did not influence the development of strictures, intraabdominal and perianal penetrating complications, or increased resectional surgery, biological therapy or immunomodulators requirements.

CONCLUSIONS

Patients who develop CD while smoking seem to have a similar disease course to those who never smoked.

Childhood onset of Crohn disease: experience from a university teaching hospital in Saudi Arabia

BACKGROUND AND OBJECTIVES

Crohn disease (CD) is an increasingly recognized problem in Saudi Arabia. The aim of this study was to describe the clinical pattern in children and adolescents with CD seen at King Abdulaziz University Hospital (KAUH), Jeddah, Saudi Arabia.

DESIGN AND SETTING

Retrospective hospital-based study conducted on data collected for the period between January 2001 and March 2010.

PATIENTS AND METHODS

Data for all children and adolescents diagnosed at KAUH with CD in the period were retrieved and analyzed.

RESULTS

Ninety-six patients were identified. The median age at diagnosis was 11.3 years (range, 0.12-17.6 years). Fifty (52.1%) were males. Sixty-four (66.7%) were Saudis. Nine (9.4%) had a first degree relative with inflammatory bowel disease. The most common presenting symptoms were diarrhea (88.5%), weight loss (84.2%) and anorexia (80.2%). At least one extraintestinal manifestation occurred in 24% of patients. Forty-two percent were underweight and 19% had short stature. The most common distribution was ileocolonic (37.5%), followed by colonic in 31.2%. Twenty-five (26%) patients had perianal disease, 13 (13.5%) had strictures and 15 (15.6%) had penetrating disease. Laboratory investigations revealed anemia in 84.4%, thrombocytosis in 50%, hypoalbuminemia in 64.6%, elevated erythrocyte sedimentation rate (ESR) in 50% and elevated C-reactive protein in 58.3%. Induction of remission was achieved with enteral nutrition in 20% of patients and with corticosteroids in the remaining.

CONCLUSIONS

The clinical pattern of CD in children from the Western Province of Saudi Arabia was found to be similar to reports from the West. Pediatricians should be aware of the varying presentations of CD. Early referral to specialized centers is crucial.

Anti-Saccharomyces cerevisiae antibodies associate with phenotypes and higher risk for surgery in Crohn's disease: a meta-analysis

BACKGROUND

Recent studies suggested that anti-Saccharomyces cerevisiae antibody (ASCA) status was associated with diagnostic findings, stratified classification phenotypes, disease activity and clinical course of Crohn's disease (CD). However, the relationship between ASCA status and phenotypes of CD remains controversial in these studies.

AIMS

The purpose of this study was to evaluate whether ASCA status is associated with the phenotypes and the risk of surgery in diverse populations in CD.

METHODS

We conducted a meta-analysis of studies assessing the association of ASCA status with phenotypes and risk of surgery in CD. Three independent reviewers undertook data extraction. We pooled odds ratios separately for the cohort and case-control studies.

RESULTS

We identified ten cohort studies (n = 2,365) and 14 case-control studies (n = 1,887) that investigated the association of ASCA status with phenotypes and risk of surgery in CD. The meta-analysis of the cohort studies showed significant association between the ASCA-positive status and higher risk of early-onset age (OR 2.25, 95 % CI 1.41-3.57, P < 0.001), ileal involvement disease (1.70, 1.05-2.77, P = 0.03), complicated disease behavior (2.09, 1.71-2.57, P < 0.001), perianal disease (1.49, 1.14-1.94, P = 0.004), and risk for surgery (1.61, 1.29-2.01, P < 0.001). Meta-analysis of the case-control studies also showed a significantly higher risk in ileal involvement disease (1.77, 1.25-2.49, P = 0.001), complicated disease behavior (2.13, 1.70-2.68, P < 0.001), perianal disease (1.96, 1.38-2.78, P < 0.001), and risk for surgery (1.71, 1.17-2.49, P = 0.005), except for the early-onset age (1.16, 0.80-1.69, P = 0.44).

CONCLUSIONS

This meta-analysis indicated that positive ASCA status is a risk factor for early-onset age, ileal involvement, complicated behavior, perianal disease and requirement for surgery in CD.

Effects of family history on inflammatory bowel disease characteristics in Japanese patients

BACKGROUND

Although the prevalence of inflammatory bowel disease (IBD) is reported to have reached a plateau in Western countries, it is increasing in Asia. The etiology of IBD is still under investigation. We performed an epidemiological study to clarify the characteristics of IBD in Japan, focusing on patients' family history.

METHODS

We obtained clinical data on ulcerative colitis (UC) (46,114 cases) and Crohn's disease (CD) (11,305 cases) in 2007 from an electronic database maintained under the Japanese Ministry of Health, Labour and Welfare's nationwide registry system, and analyzed the differences in disease characteristics between patients with IBD who had a family history of the disease and those who did not.

RESULTS

A total of 2.7% of the patients with UC and 2.6% of those with CD had a family history. The present age and age at disease onset were lower among the patients with UC who had a family history than among those without (present age: p < 0.001; age at disease onset: p < 0.001; Mann-Whitney U-test), but no similar trend was observed in the patients with CD. Disease severity was worse among both the UC and CD patients with a family history. The clinical course of patients with UC was not affected by family history. Levels of independence in daily life were associated with family history among CD patients, whereas age was associated with levels of independence in daily life among UC patients.

CONCLUSION

Disease characteristics of IBD vary in some aspects according to the presence or absence of a family history.

Serological antibodies in inflammatory bowel disease: a systematic review

The diagnosis of inflammatory bowel disease (IBD) is traditionally based on a combination of clinical, endoscopic, histological, and radiological criteria. However, further testing is needed in cases of diagnostic uncertainty and in predicting disease course. This systematic review focuses on the potential for 10 serological antibodies to fill these roles: pANCA, ASCA, anti-OmpC, anti-CBir1, anti-I2, ALCA, ACCA, AMCA, anti-L, and anti-C. We discuss their prevalence in IBD and health; their role in disease diagnosis and risk stratification; their stability over time; their presence in unaffected relatives; their association with genetic variants; and differences across ethnic groups. Serological antibodies have some role in primary diagnosis and in differentiating between Crohn's disease and ulcerative colitis. In indeterminate colitis, preoperative measurement of serological antibodies can help to predict the likelihood of complications among patients undergoing pouch surgery. The combined presence and magnitude of a large panel of antibodies appear to be of value in predicting disease progression. There is currently insufficient evidence to recommend the use of antibody testing to predict responses to treatment or surgery in patients with IBD.

Does capsule endoscopy have an added value in patients with perianal disease and a negative work up for Crohn's disease?

AIM: To investigate the role of capsule endoscopy in patients with persistent perianal disease and negative conventional work up for Crohn’s disease (CD).

METHODS: Patients with perianal disease (abscesses, fistulas, recurrent fissures) were evaluated for underlying CD. Patients who had a negative work up, defined as a negative colonoscopy with a normal ileoscopy or a normal small bowel series or a normal CT/MR enterography, underwent a Pillcam study of the small bowel after signing informed consent. Patients using nonsteroidal anti-inflammatory drugs or who had a history of inflammatory bowel disease or rheumatic disease were excluded.

RESULTS: We recruited 26 patients aged 21-61 years (average 35.6 years), 17 males and 9 females. One case could not be evaluated since the capsule did not leave the stomach. In 6 of 25 (24%) patients with a negative standard work up for Crohn's disease, capsule endoscopy (CE) findings were consistent with Crohn's disease of the small bowel. Family history of CD, white blood cell, hemoglobin, erythrocyte sedimentation rate or C-reactive protein did not predict a diagnosis of CD. Capsule endoscopy findings led to a change in treatment.

CONCLUSION: In patients with perianal disease and a negative conventional work up to exclude CD, CE leads to incremental diagnostic yield of 24%.

Clinical and genetic risk factors for perianal Crohn's disease in a population-based cohort

OBJECTIVES

Perianal Crohn's disease (CD) affects around one-quarter of CD patients and represents a distinct disease phenotype. The objective of this study was to investigate a large population-based cohort of inflammatory bowel disease (IBD) patients to identify clinical and genetic risk factors for perianal CD.

METHODS

Data were collected in the Canterbury IBD database, estimated to include 91% of all patients with IBD in Canterbury, New Zealand. Genotyping was performed for selected loci previously demonstrated to be associated with CD. Patients with perianal disease were then compared with both CD patients without perianal disease and healthy controls to assess the presence of potential phenotypic, environmental, and genetic risk factors.

RESULTS

Of the 715 CD patients in the database, 190 (26.5%) had perianal disease. In all, 507 patients with genotype data available were analyzed. Perianal disease was associated with younger age at diagnosis (P < 0.0001), complicated intestinal disease (P < 0.0001), and ileal disease location (P = 0.002). There was no association with gender, ethnicity, smoking, or breast feeding. Genotype analysis revealed an association with the neutrophil cytosolic factor 4 (NCF4) gene compared with both non-perianal CD patients (odds ratio (OR): 1.47; 95% confidence interval (CI): 1.08-1.99) and healthy controls (OR: 1.47; 95% CI: 1.10-1.95). There was no association identified with other genes, including IBD5 (OR: 0.91; 95% CI: 0.69-1.20), tumor necrosis factor α (OR: 1.04; 95% CI: 0.56-1.85), and IRGM (immunity-related guanosine triphosphatase protein type M) (OR: 1.21; 95% CI: 0.80-1.82).

CONCLUSIONS

This study suggests that younger age at diagnosis, complicated disease behavior, and ileal disease location are risk factors for perianal CD. In addition, this paper represents the first report of an association of the NCF4 gene with perianal disease.

Clinical and pathological analysis of colonic Crohn's disease, including a subgroup with ulcerative colitis-like features

Little is known regarding the clinical and, in particular, pathological manifestations of patients with isolated colonic Crohn's disease. The purpose of this study was to evaluate the clinical and pathological features of patients with Crohn's disease limited to the colon at initial presentation, and to determine whether there are any histological features that are predictive of outcome after surgery. The clinical features, outcome after surgery, and pathological features of colonic resection specimens of 73 patients who presented initially with isolated colonic Crohn's disease were evaluated and compared with 45 Crohn's disease patients who presented initially with both ileal and colonic involvement. Clinically, patients with isolated colonic Crohn's disease presented at a significantly older age at the time of diagnosis, and had a significantly shorter duration of colitis before surgical resection, than did patients with ileocolonic Crohn's disease at disease onset. Pathologically, patients with isolated colonic Crohn's disease showed a significantly higher proportion of cases with subtotal, total, or left-sided colitis, and significantly fewer strictures/stenosis, pericolonic adhesions, pyloric metaplasia, and cases with proximal worse than distal colonic disease. Overall, patients with isolated colonic Crohn's disease showed a trend toward a lower number of major microscopic Crohn's disease features. A small proportion of patients from both Crohn's disease groups (14% and 13%, respectively) showed inflammatory disease limited to the mucosa, without mural involvement, reminiscent of ulcerative colitis, and these were termed 'ulcerative colitis-like Crohn's disease'. These patients were significantly younger than those with mural involvement. Overall, 44% of patients from both Crohn's disease groups developed at least one adverse outcome, and neither the number nor the type of major Crohn's disease features correlated with adverse outcome. Patients with isolated colonic involvement have distinctive clinical and pathological features. A small subgroup of Crohn's patients shows only mucosal involvement reminiscent of ulcerative colitis.

Are inherited thrombotic risk factors associated with fibrostenosis in Crohn's disease?

BACKGROUND

Fibrostenotic lesions are common complications in Crohn's disease (CD) often requiring surgery. Inherited thrombotic risk factors are associated with fibrosis in other chronic inflammatory diseases. The aim of the study was to assess whether inherited thrombotic risk factors are associated with fibrostenosis in CD.

METHODS

Clinical data on 529 CD patients were collected retrospectively. Subjects were tested for and grouped according to the presence of factor V Leiden (FVL), the prothrombin G20210A, and the methylenetetrahydrofolate reductase C677T mutation (MTHFR). Patients who underwent CD-related intestinal surgery were assessed for the presence of fibrostenosis, which was the primary endpoint. The diagnosis of fibrostenosis was based on surgical, pathological, and histopathological reports. A Cox proportional hazards model was used for statistical analysis.

RESULTS

Thirty-two (6.1%, heterozygous 30, homozygous 2) patients were carriers of FVL, 19 (3.6%, all heterozygous) carried the prothrombin variant, and 318 (60.1%) the MTHFR variant (243 heterozygous, 75 homozygous). In all, 303 (57.3%) patients underwent intestinal surgery. Fibrostenosis was identified in 219 (72.3%) surgical specimens. The rate of first intestinal surgeries with fibrostenosis tended to be more frequent in patients with the homozygous 677TT MTHFR mutation (hazard ratio, HR 1.39; 95% confidence interval [CI]: 0.98-1.97; P = 0.067). After adjustment for potential confounders homozygous 677TT MTHFR mutation did not remain a risk factor for intestinal surgery with fibrostenosis (HR 1.23; 95% CI: 0.77-1.98; P = 0.387). FVL and the prothrombin variant had no influence on the primary endpoint.

CONCLUSIONS

The MTHFR 677TT mutation, factor V Leiden, and the prothrombin G20210A mutation are not associated with fibrostenosis in CD.

The Montreal classification for Crohn's disease: clinical application to a Brazilian single-center cohort of 90 consecutive patients

CONTEXT

Crohn's disease presents very heterogeneous features from a clinical point of view, and classifying Crohn's disease patients in homogeneous subgroups in the light of genetic, molecular and clinical aspects is challenging. The Montreal Classification for Crohn's disease was proposed in 2005 as an effort to characterize Crohn's disease patients according to recent clinical and research advances in the field of inflammatory bowel disease. Since its proposition, the Montreal Classification needs an ample validation and application among different populations around the world. To date, there are no known studies applying the Montreal Classification to a Brazilian cohort of Crohn's disease patients.

OBJECTIVES

To apply the Montreal Classification to a Brazilian cohort of Crohn's disease patients at a referral center for inflammatory bowel disease in Northwestern São Paulo State, Brazil.

METHODS

We selected 90 consecutive well-characterized Crohn's disease patients assisted at Inflammatory Bowel Disease Outpatient Clinic between January 1992 and January 2007, with a minimum follow-up of 2 years; data concerning demographic characteristics, clinical onset of disease, age at diagnosis, time of disease, location and behavior of disease, presence of extraintestinal manifestations, familial occurrence, perianal involvement, treatment with biological drugs, and history of surgical treatment were evaluated.

RESULTS

Male patients were predominant (54%), with a mean age at diagnosis of 33 ± 14 years old, and a median followup of 5.5 years. Most of the patients were diagnosed between 17 and 40 years old (59%), and had disease located in terminal ileum 46%), with a nonstricturing, nonpenetrating behavior (71%). Time of disease was correlated with necessity of biological treatment, disease behavior, and surgical treatment (P<0.05).

CONCLUSIONS

These study findings are consistent with results from other studies conducted among different populations, although a further multicentric study with a larger number of patients would be necessary to validate the Montreal Classification among Brazilian population.

The prognostic power of the NOD2 genotype for complicated Crohn's disease: a meta-analysis

OBJECTIVES

Crohn's disease is often purely inflammatory at presentation, but most patients develop strictures and fistulae over time (complicated disease). Many studies have suggested that nucleotide-binding oligomerization domain 2 (NOD2) mutations are associated with a varying but increased risk of complicated disease. An accurate and sufficiently powerful predictor of complicated disease could justify the early use of biological therapy in high-risk individuals. We performed a systematic review and meta-analysis to obtain accurate estimates of the predictive power of the identified mutations (such as p.R702W, P.G908R, and p.Leu1007fsX1008) in NOD2 for the risk of complicated disease.

METHODS

An electronic search of MEDLINE, Embase, and Web of Science identified 917 relevant papers. Inclusion required specification of genetic mutations at the individual level and disease phenotypes by Vienna classification (inflammatory (B1), stricturing (B2), and fistulizing (B3)). A total of 49 studies met these criteria, which included 8,893 subjects, 2,897 of whom had NOD2 mutations. Studies were weighted by median disease duration. Studies not providing duration data were weighted at the level of the study with the shortest disease duration (3.9 years).

RESULTS

The relative risk (RR) of the presence of any NOD2 mutant allele for complicated disease (B2 or B3) was 1.17 (95% confidence interval (95% CI) 1.10-1.24; P<0.001). P.G908R was associated with an RR of complicated disease of 1.33 (95% CI 1.11-1.60; P=0.002). NOD2 did not predict perianal disease (P=0.4). The RR of surgery was 1.58 (95% CI 1.38-1.80; P<0.001). There was substantial heterogeneity across all studies (I(2)=66.7%). On the basis of logistic regression of these data, the sensitivity of any mutation in predicting complicated disease was 36% and specificity was 73%, with the area under the receiver operating characteristic curve 0.56.

CONCLUSIONS

The presence of a single NOD2 mutation predicted an 8% increase in the risk for complicated disease (B2 or B3), and a 41% increase with 2 mutations. Surgery risk is increased by 58% with any NOD2 mutation, whereas perianal disease was unchanged. The predictive power associated with a single NOD2 mutation is weak. The RR of any NOD2 mutations for complicated disease was only 17% across 36 studies. However, the presence of two NOD2 mutations had 98% specificity for complicated disease. These data provide insufficient evidence to support top-down therapy based solely on single NOD2 mutations, but suggest that targeted early-intensive therapy for high-risk patients with two NOD2 mutations might be beneficial, if prospective trials can demonstrate changes in the natural history in this subset of patients.

Risk factors associated with progression to intestinal complications of Crohn's disease in a population-based cohort

BACKGROUND AND AIMS

We sought to assess the evolution of Crohn's disease behavior in an American population-based cohort.

METHODS

Medical records of all Olmsted County, Minnesota residents who were diagnosed with Crohn's disease from 1970 to 2004 were evaluated for their initial clinical phenotype, based on the Montreal Classification. The cumulative probabilities of developing structuring and/or penetrating complications were estimated using the Kaplan-Meier method. Proportional hazards regression was used to assess associations between baseline risk factors and changes in behavior.

RESULTS

Among 306 patients, 56.2% were diagnosed between the ages of 17 and 40 years. Disease extent was ileal in 45.1%, colonic in 32.0%, and ileocolonic in 18.6%. At baseline, 81.4% had nonstricturing nonpenetrating disease, 4.6% had stricturing disease, and 14.0% had penetrating disease. The cumulative risk of developing either complication was 18.6% at 90 days, 22.0% at 1 year, 33.7% at 5 years, and 50.8% at 20 years after diagnosis. Among 249 patients with nonstricturing, nonpenetrating disease at baseline, 66 changed their behavior after the first 90 days from diagnosis. Relative to colonic extent, ileal, ileocolonic, and upper GI extent were significantly associated with changes in behavior, whereas the association with perianal disease was barely significant.

CONCLUSIONS

In a population-based cohort study, 18.6% of patients with Crohn's disease experienced penetrating or stricturing complications within 90 days after diagnosis; 50% experienced intestinal complications 20 years after diagnosis. Factors associated with development of complications were the presence of ileal involvement and perianal disease.

The impact of smoking in Crohn's disease: no smoke without fire

Smoking habit is the most widely accepted environmental factor affecting the incidence and disease progression in the inflammatory bowel diseases. The contrasting effects in Crohn's disease (CD) and ulcerative colitis are unexplained. The purpose of this review is to summarise the existing data on the effects of smoking in CD on disease history, recurrence after surgery, effects on drug responses and to review available evidence that carriage of some of the known susceptibility genes may be disproportionate in smokers with CD. The review also highlights potential mechanisms involved and factors that might affect patients' smoking habits. The clinical and scientific implications of the data are discussed.

Ileal disease is associated with surgery for perianal disease in a population-based Crohn's disease cohort

BACKGROUND

The aim of this study was describe the frequency and characteristics of perianal surgical intervention (PSI) for Crohn's disease in a population-based cohort of patients with inflammatory bowel disease (IBD).

METHODS

A total of 1421 patients with IBD were recruited, representing approximately 91 per cent of people with IBD in Canterbury, New Zealand. The clinical notes were screened to confirm the diagnosis and extract clinical data, including details of PSIs.

RESULTS

Some 649 patients with Crohn's disease were included in the analysis, of whom 119 (18.3 per cent) had at least one PSI. Of these, 61 (51.3 per cent) required further procedures. Operations for perianal abscess and fistula accounted for 72.4 per cent of interventions. PSI rates did not differ between the sexes (P = 0.218). Age less than 17 years (adjusted odds ratio (OR) 1.89 (95 per cent confidence interval 1.08 to 3.28)) and ileal disease (OR 1.76 (1.06 to 2.92)) were identified as predictors of PSI. As disease duration increased, so did the proportion of patients with complicated intestinal disease among those who had undergone PSI. The median time to first PSI from diagnosis of Crohn's disease was 28 (interquartile range 7-82) months. Sex, age at diagnosis and disease location did not influence the time to first PSI.

CONCLUSION

PSIs are frequent in patients with Crohn's disease, particularly those with ileal disease and those diagnosed at a young age.

Dissecting genetic predisposition to inflammatory bowel disease: current progress and prospective application

Over the last 10 years, sensitive advancement has been made in the study of genetic susceptibility to inflammatory bowel disease (IBD). Complementary methodologies of linkage, fine-mapping and candidate-gene studies have led to the identification of a number of susceptibility genes and loci, including caspase activation and recruitment domain 15 (CARD15), major histocompatibility complex (MHC) and IBD5, whereas many other genes (nucleotide oligomerization domain 1 [NOD1], tumor-upregulated CARD-containing antagonist of caspase-9 [TUCAN], Toll-like receptors [TLR], interleukin 23 receptor [IL23R], multidrug resistance 1 [MDR1], myosin IXb [MYO9B], chemokine [C-Cmotif] ligand 20 [CCL20], human beta-defensin 2 [HBD-2], autophagy-related 16-like 1 [ATG16L1]) are still awaiting confirmation. The CARD15 gene is currently the most widely replicated and investigated gene. The exact sequence of events that link CARD15 variants to early pathogenetic changes is unknown. However, the role of the encoded protein confirms the relevance of appropriate responses by the innate immune system to intestinal bacteria, including the production of antimicrobial peptides (defensins). With the implementation of new genomics and proteomics methodologies, genetic research will advance our further understanding of the clinical heterogeneity of IBD and tackle the complex interactions between genetic and environmental risk factors.

Genetic dissection of inflammatory bowel disease: unravelling etiology and improving diagnostics

Over the past 10 years, remarkable advances in the mapping and identification of genes involved in susceptibility to inflammatory bowel disease have been witnessed. Most notable among these advances has been the discovery of variants in the CARD15, DLG5, SLC22A4 and SLC22A5 genes, which are associated with increased risk of inflammatory bowel disease or specifically Crohn's disease. These discoveries have provided critical new insights into the molecular pathophysiology of inflammatory bowel disease and the pathways wherein genetic and environmental factors such as enteric bacterial flora may interact to trigger immune dysregulation and intestinal inflammation. This review will outline the discovery of these inflammatory bowel disease-related genes, describe future prospects for further inflammatory bowel disease gene identification, and consider the impact of a genetic understanding of inflammatory bowel disease on future clinical practice.

Incidence of stricturing and penetrating complications of Crohn's disease diagnosed in pediatric patients

BACKGROUND

The development of disease complications is poorly characterized in pediatric patients with Crohn's disease (CD).

METHODS

We retrospectively determined the cumulative incidence of stricturing and penetrating complications of CD prior to first surgery utilizing data from 989 consecutively enrolled CD patients (age 0-17 years at diagnosis) collected between January 2000 and November 2003 and stored in the Pediatric IBD Consortium Registry.

RESULTS

Mean age at diagnosis was 11.5 +/- 3.8 (standard deviation) years. Median follow-up time was 2.8 years. Prior to first surgery, the cumulative incidence of stricturing or penetrating complications was 27% at 5 years and 38% at 10 years from the diagnosis of inflammatory bowel disease. The cumulative incidence of complicated disease was lowest in isolated colonic disease (P = 0.009). Penetrating complications that followed stricturing complications prior to first surgery occurred within 2 years of stricturing complications (cumulative incidence was 13% at 2 years from diagnosis of stricturing disease). Stricturing complications that followed penetrating complications prior to first surgery occurred within 8 years of penetrating complications (cumulative incidence was 26% at 8 years from diagnosis of penetrating complications).

CONCLUSIONS

Strictures, abscesses, and fistulas are common in pediatric CD. Earlier aggressive management may be indicated. Prospective study is required to identify genetic and serologic markers that predict a patient's risk for the development of complicated disease and to determine optimal treatment regimens.

Association of the novel serologic anti-glycan antibodies anti-laminarin and anti-chitin with complicated Crohn's disease behavior

BACKGROUND

We tested a panel of novel serological anti-glycan antibodies including the previously unpublished anti-laminarin IgA (Anti-L) and anti-chitin IgA (Anti-C) carbohydrate antibodies for the presence in Crohn's disease (CD) patients, diagnosis and differentiation of CD, association with complicated disease behavior, and marker stability over time.

METHODS

The presence of Anti-L, Anti-C, anti-chitobioside IgA (ACCA), anti-laminaribioside IgG (ALCA), anti-mannobioside IgG (AMCA), and anti-Saccaromyces cervisiae IgG (gASCA) carbohydrate antibodies were tested in serum samples from 824 participants (363 CD, 130 ulcerative colitis [UC], 74 other gastrointestinal diseases, and 257 noninflammatory bowel/gastrointestinal disease controls) of the German IBD-network by enzyme-linked immunosorbent assay (ELISA; Glycominds, Lod, Israel) and for perinuclear antineutrophil cytoplasmic antibody (pANCA) by immunofluorescence.

RESULTS

In all, 77.4% of the CD patients were positive for at least 1 of the anti-glycan antibodies. gASCA or the combination of gASCA/pANCA remained most accurate for the diagnosis of CD, but the combined use of the antibodies improved differentiation of CD from UC. Several single markers as well as an increasing antibody response were independently linked to a severe disease phenotype, as shown for the occurrence of complications, CD-related surgery, early disease onset, and ileal disease location. This was observed for both quantitative and qualitative antibody responses. The antibody status remained stable over time in most IBD patients.

CONCLUSIONS

A panel of anti-glycan antibodies including the novel Anti-L and Anti-C may aid in differentiation of CD from UC, is associated with complicated CD behavior and IBD-related surgery, and is stable over time in a large patient cohort.

NOD2 mutations and anti-Saccharomyces cerevisiae antibodies are risk factors for Crohn's disease in African Americans

OBJECTIVES

NOD2 mutations and anti-Saccharomyces cerevisiae antibodies (ASCAs) are established risk factors of Crohn's disease (CD) in whites but have not been assessed in African-American (AA) adults with CD.

METHODS

AAs with CD and controls were recruited by the Mid-Atlantic African-American IBD Study as part of the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) IBD Genetics Consortium. Genotyping for the three common CD NOD2 mutations (Leu1007fsinsC, G908R/2722g>c, and R702W/2104c>t) and ASCA enzyme-linked immunosorbent assays were performed in 183 AA CD patients and in 143 controls. Logistic regression was used to calculate adjusted odds ratios (ORs) for the association between ASCA and disease phenotype.

RESULTS

ASCA sensitivity and specificity values were 70.5 and 70.4%, respectively. On univariate analysis, ASCA was significantly associated with younger age at diagnosis, ileal involvement, and complicated (stricturing/penetrating) behavior. On multivariate analysis, ASCA titer (per 25 Units) was associated with ileal involvement (OR 1.18, 95% confidence interval (CI): 1.04-1.34), complicated behavior (OR 1.13, 95% CI: 1.01-1.28), and surgery (hazard ratio: 1.11, 95% CI: 1.02-1.21). Cigarette smoking and CD family history were also significantly associated with surgery. NOD2 carriers (all heterozygotes) were more common among CD cases than controls (8.2 vs. 2.1%; OR 4.17%, 95% CI: 1.18-14.69). The NOD2 mutation population attributable risk was 6.2%.

CONCLUSIONS

In comparison with whites, ASCA in AAs has a similar sensitivity but a lower specificity for CD. ASCA is associated with ileal involvement, complicated behavior, and surgery in AAs with CD. NOD2 is a risk gene for AA CD, although mutation frequency and population attributable risk are much lower than in whites.

Anti-Saccharomyces cerevisiae antibodies status is associated with oral involvement and disease severity in Crohn disease

OBJECTIVES

To determine anti-Saccharomyces cerevisiae antibodies (ASCA) status and its relation to disease phenotype in patients with inflammatory bowel disease (IBD).

PATIENTS AND METHODS

A total of 301 Scottish patients with early-onset IBD-197 Crohn disease (CD), 76 ulcerative colitis (UC), 28 indeterminate colitis (IC)-and 78 healthy control individuals were studied. ASCA status (IgA, IgG) was determined by enzyme-linked immunosorbent assay. ASCA status was then analyzed in relation to CD phenotype.

RESULTS

Patients with CD had a higher prevalence of ASCA than patients with UC and healthy controls: 82/197 versus 12/76, odds ratio (OR) 3.80 (1.93-7.50) and 82/197 versus 6/78, OR 8.56 (3.55-20.62), respectively. Univariate analysis showed that positive ASCA status was associated with oral CD (17/25 vs 59/153, OR 3.39 [1.38-8.34]), perianal CD (39/77 vs 38/108, OR 1.89 [1.04-3.44]) and the presence of granulomata (63/132 vs 15/52, OR 2.25 [1.13-4.48]) and also with markers of disease severity: raised C-reactive protein (44/90 vs 12/49, OR 2.95[1.36-6.37]), hypoalbuminemia (44/85 vs 20/74, OR 2.28[1.19-4.37]), and surgery (27/49 vs 54/147, OR 2.11 [1.10-4.06]). From multivariate analysis, the presence of oral disease (adjusted P = 0.001, OR 22.22 [3.41-142.86]) and hypoalbuminemia (adjusted P = 0.01, OR 4.78 [1.40-16.39]) was found to be independently associated with ASCA status. No association was demonstrated between ASCA and IBD candidate genes.

CONCLUSIONS

Patients with CD had a higher prevalence of ASCA than did other patients with IBD. ASCA status described patients with CD who had a specific phenotype, showing an association with markers of disease severity and oral CD involvement.

Disease behavior in children with Crohn's disease: the effect of disease duration, ethnicity, genotype, and phenotype

BACKGROUND

Disease behavior in Crohn's disease (CD) may be modified by disease location and genotype. Disease behavior may change over time, and thus analysis requires follow-up. To date, there have been few pediatric studies that have evaluated the association between disease behavior and genotype with prolonged follow-up. The aim of our study was to evaluate the effect of genotype, phenotype, and ethnicity on disease behavior in pediatric CD.

METHODS

Evaluation of 128 pediatric CD was followed by analysis of 232 pediatric and adult-onset CD patients. Inclusion required at least 2 years of follow-up. Phenotype, ethnicity, and disease duration were recorded. Patients were genotyped for polymorphisms in the NOD2/CARD15 gene.

RESULTS

Colonic involvement was more frequent in younger patients. Pediatric disease at end of follow-up was classified as inflammatory (78%), penetrating (7%), and stricturing (17%). Duration of follow-up (mean 4.9 pediatric and 6.4 years mixed) was associated with more stricturing and penetrating disease. There was no association between mean age of onset and NOD2/CARD15, or either of these with disease behavior. These observations were replicated in the mixed cohort. Sephardic Jewish origin was inversely correlated with inflammatory behavior (P = 0.006), independent of NOD2/CARD15 genotype.

CONCLUSIONS

Duration of disease and ethnicity, irrespective of NOD2/CARD15 genotype and age of onset, were the only predictors for penetrating or stricturing disease.

Clinical and molecular characteristics of isolated colonic Crohn's disease

BACKGROUND

Clinical, serological, and molecular data support the existence of discrete subsets of Crohn's disease (CD) defined by location of disease. Little is known about the epidemiology and natural history of isolated CD of the colon (Montreal Classification L2) because most studies have not accurately distinguished it from ileocolonic disease. Our objectives were to describe the clinical features and natural history of isolated colonic CD in a rigorously characterized patient cohort and to investigate the association of polymorphisms in a number of genes with colonic location of disease and disease behavior.

METHODS

Patients with L2 disease were identified from a database of 675 CD patients. Only patients with a normal small bowel enema (70%), ileoscopy alone (30%), or both (20%) were included. Genotyping was performed using PCR-SSP or the iPLEX platform.

RESULTS

In all, 135 patients were classified with L2 disease. L2 disease was more common in women (74.0% versus 58.0%; P = 0.0004; odds ratio [OR] = 2.11, 95% confidence interval [CI] 1.36-3.26) and in never smokers (48.9% versus 36.9%; P = 0.008; OR = 1.64, 95% CI 1.09-2.45); 20.7% underwent colonic resection for severe disease. We confirmed that carriage of the HLA-DRB1*0103 allele is strongly associated with isolated colonic CD (14.9% versus 4.0%; P = 0.000016; OR 4.6, 95% CI 2.25-9.47) and report the novel association of this allele with time to first surgical event (log rank P = 0.001). There was no association with any of the known CD susceptibility loci (NOD2, IBD5, NOD1, IL23R, ATG16L1) and isolated colonic CD. A nonsynonymous polymorphism in MEKK1 (rs832582) was associated with CD susceptibility overall (15% versus 19%; P = 0.0083; OR = 1.28, 95% CI 1.07-1.54). The association was strongest in those patients not carrying a NOD2 mutation and had no effect on disease location.

CONCLUSIONS

This study describes the clinical features of isolated colonic CD and demonstrates the importance of the HLA region in determining the molecular basis of colonic inflammation.

Recognition of luminal bacterial antigens in inflammatory bowel disease

The incidence of inflammatory bowel disease (IBD) is increasing all over the world. However, it is rather difficult to treat IBD because its etiological factors and pathogenesis are still not clear. In recent years, the researches about the relationship between luminal bacterial antigens and IBD have provided new advances for its etiology and pathogenesis. We, in this paper, describe the present status in the recognition of luminal bacterial antigens in IBD patients which is correlated to the clinical phenotypes, prognosis and familial genetics of this disease, thus contributing to the treatment for IBD.

Definition of phenotypic characteristics of childhood-onset inflammatory bowel disease

BACKGROUND & AIMS

Childhood-onset inflammatory bowel disease (IBD) might be etiologically different from adult-onset IBD. We analyzed disease phenotypes and progression of childhood-onset disease and compared them with characteristics of adult-onset disease in patients in Scotland.

METHODS

Anatomic locations and behaviors were assessed in 416 patients with childhood-onset (276 Crohn's disease [CD], 99 ulcerative colitis [UC], 41 IBD type unclassified [IBDU] diagnosed before seventeenth birthday) and 1297 patients with adult-onset (596 CD, 701 UC) IBD using the Montreal classification.

RESULTS

At the time of diagnosis in children, CD involved small bowel and colon (L3) in 51% (138/273), colon (L2) in 36%, and ileum (L1) in 6%; the upper gastrointestinal (GI) tract (L4) was also affected in 51%. In 39%, the anatomic extent increased within 2 years. Behavioral characteristics progressed; 24% of children developed stricturing or penetrating complications within 4 years (vs 9% at diagnosis; P < .0001; odds ratio [OR], 3.32; 95% confidence interval [CI], 1.86-5.92). Compared with adults, childhood-onset disease was characterized by a "panenteric" phenotype (ileocolonic plus upper GI [L3+L4]; 43% vs 3%; P < .0001; OR, 23.36; 95% CI, 13.45-40.59) with less isolated ileal (L1; 2% vs 31%; P < .0001; OR, 0.06; 95% CI, 0.03-0.12) or colonic disease (L2; 15% vs 36%; P < .0001; OR, 0.31; 95% CI, 0.21-0.46). UC was extensive in 82% of the children at diagnosis, versus 48% of adults (P < .0001; OR, 5.08; 95% CI, 2.73-9.45); 46% of the children progressed to develop extensive colitis during follow-up. Forty-six percent of children with CD and 35% with UC required immunomodulatory therapy within 12 months of diagnosis. The median time to first surgery was longer in childhood-onset than adult-onset patients with CD (13.7 vs 7.8 years; P < .001); the reverse was true for UC.

CONCLUSIONS

Childhood-onset IBD is characterized by extensive intestinal involvement and rapid early progression.

Current understanding of fungal microflora in inflammatory bowel disease pathogenesis

Inflammatory bowel diseases are a current and growing public health problem, with a prevalence that appears to be increasing in most countries and cultures. While most research into the triggering phenomenon has focused on the interaction between commensal bacteria and inflammatory bowel disease, enteric fungi may also be important in determining disease susceptibility. Herein we review what is known about enteric fungi and the mechanisms by which they and their dysregulation might be involved in triggering inflammatory diseases of the bowel.