Expression patterns common and unique to ulcerative colitis and celiac disease.

Autoimmune diseases like celiac disease (CeD) and ulcerative colitis (UC) show a common genetic background defined by the existence of shared susceptibility loci. We aimed to go deeper into this common genetic background through performing a cross-disease study based on gene expression. We measured the expression of 21 genes located in 13 CeD-UC susceptibility regions, and 10 genes in five CeD risk regions. Determinations were carried out in colon/rectum samples from 13 UC patients (inflamed and uninflamed tissue) and four colon samples from controls. Duodenal samples from 19 CeD patients and 12 controls were used for comparisons. Differences were analyzed using the Bayesian method. The shared chromosomal regions containing TNFAIP3, PTPN2, ICOSLG, C1orf106, and IL21 showed similar results in both diseases. FASLG, PLEK, CCR4, and TAGAP, all located in CeD risk loci, were up-regulated in both CeD and UC patients. Finally, ZFP36L1, ZMIZ1, PUS10, UBE2L3, and BACH2 showed opposite results in CeD and UC. A high complexity underlies autoimmune common susceptibility loci, as the expression pattern of the studied genes does not always correlate with the one expected attending to the apparent genetic background. Differentially expressed genes such as ZFP36L1, ZMIZ1, PUS10, and BACH2 deserve further research in autoimmune diseases.

Response to Infliximab in Crohn's Disease: Genetic Analysis Supporting Expression Profile.

Substantial proportion of Crohn's disease (CD) patients shows no response or a limited response to treatment with infliximab (IFX) and to identify biomarkers of response would be of great clinical and economic benefit. The expression profile of five genes (S100A8-S100A9, G0S2, TNFAIP6, and IL11) reportedly predicted response to IFX and we aimed at investigating their etiologic role through genetic association analysis. Patients with active CD (350) who received at least three induction doses of IFX were included and classified according to IFX response. A tagging strategy was used to select genetic polymorphisms that cover the variability present in the chromosomal regions encoding the identified genes with altered expression. Following genotyping, differences between responders and nonresponders to IFX were observed in haplotypes of the studied regions: S100A8-S100A9 (rs11205276* G/rs3014866* C/rs724781* C/rs3006488* A; P = 0.05); G0S2 (rs4844486* A/rs1473683* T; P = 0.15); TNFAIP6 (rs11677200* C/rs2342910* A/rs3755480* G/rs10432475* A; P = 0.10); and IL11 (rs1126760* C/rs1042506* G; P = 0.07). These differences were amplified in patients with colonic and ileocolonic location for all but the TNFAIP6 haplotype, which evidenced significant difference in ileal CD patients. Our results support the role of the reported expression signature as predictive of anti-TNF outcome in CD patients and suggest an etiological role of those top-five genes in the IFX response pathway.

Imaging Crohn disease: MR enterography.

Magnetic resonance enterography in Crohn disease management has been rapidly growing in importance during recent years. Being familiar to this technique is essential for radiologists and also, to some extent, for gastroenterologists. Our aim is to study and describe the imaging findings in magnetic resonance enterography in Crohn disease to develop a comprehensive and useful review article and imaging atlas.

A genome-wide association study on a southern European population identifies a new Crohn's disease susceptibility locus at RBX1-EP300.

OBJECTIVE: Genome-wide association studies (GWAS) have identified multiple risk loci for Crohn's disease (CD). However, the cumulative risk exerted by these loci is low, and the likelihood that additional, as-yet undiscovered loci contribute to the risk of CD is very high. We performed a GWAS on a southern European population to identify new CD risk loci. DESIGN: We genotyped 620 901 genome markers on 1341 CD patients and 1518 controls from Spain. The top association signals representing new candidate risk loci were subsequently analysed in an independent replication cohort of 1365 CD patients and 1396 controls. RESULTS: We identified a genome-wide significant association on chromosome 22q13.2 in the intergenic region between the RBX1 and EP300 genes (single nucleotide polymorphism rs4820425, OR 1.27, 95% CI 1.17 to 1.38, p=3.42E-8). We also found suggestive evidence for the association of the IFNGR2 (21q22.11), FOXP2 (7q31), MACROD2 (20p12.1) and AIF1 (6p21.3) loci with CD risk. CONCLUSIONS: In this GWAS performed on a southern European cohort, we have identified a new risk locus for CD between RBX1 and EP300. This study demonstrates that using populations of different ancestry is a useful strategy to identify new risk loci for CD.

Long-term durability of infliximab treatment in Crohn's disease and efficacy of dose "escalation" in patients losing response.

BACKGROUND: The efficacy of infliximab therapy in patients with Crohn's disease (CD) is unknown beyond 12 months. For patients who lose their initial response, consideration can be given to dose "escalation" to regain therapeutic benefit. AIM: Our primary goal was to evaluate the long-term durability of maintenance infliximab treatment. The secondary goals were to identify potential predictors of loss of infliximab efficacy, to evaluate the response to infliximab escalation, and the safety of the treatment with infliximab with and without escalation of dose. METHODS: CD patients treated with infliximab with response to an induction regimen were evaluated. Maintenance of long-term response was estimated using Kaplan-Meier analysis. The effect of specific variables was calculated using logistic regression analysis. Efficacy of dose escalation in patients who lose response to infliximab was analyzed. RESULTS: Three hundred and nine CD patients were included. The mean follow-up time with infliximab treatment was 41 months, and the majority (95%) were on concomitant immunosuppressive therapy. The annual risk of loss of response to infliximab was 12% per patient-year of treatment. After loss of response, 41% of patients were managed with infliximab therapy escalation. After the first intensified dose, 56% of patients achieved remission and 40% partial response. Concurrent immunomodulators enhanced and smoking decreased the proportion of patients who maintained response (P<0.05). CONCLUSIONS: A relevant proportion of CD patients on long-term infliximab treatment loss response. After loss of response, a high proportion of these patients initially respond to infliximab dose escalation. Concurrent immunomodulators may increase and smoking may decrease maintenance of response.

Food groups associated with immune-mediated inflammatory diseases: a Mendelian randomization and disease severity study.

BACKGROUND/OBJECTIVES: Immune-mediated inflammatory diseases (IMIDs) are prevalent diseases. There is, however, a lack of understanding of the link between diet and IMIDs, how much dietary patterns vary between them and if there are food groups associated with a worsening of the disease. SUBJECTS/METHODS: To answer these questions we analyzed a nation-wide cohort of n = 11,308 patients from six prevalent IMIDs and 2050 healthy controls. We compared their weekly intake of the major food categories, and used a Mendelian randomization approach to determine which dietary changes are caused by disease. Within each IMID, we analyzed the association between food frequency and disease severity. RESULTS: After quality control, n = 11,230 recruited individuals were used in this study. We found that diet is profoundly altered in all IMIDs: at least three food categories are significantly altered in each disease (P < 0.05). Inflammatory bowel diseases showed the largest differences compared to controls (n ≥ 8 categories, P < 0.05). Mendelian randomization analysis supported that some of these dietary changes, like vegetable reduction in Crohn's Disease (P = 2.5 × 10-10, OR(95% CI) = 0.73(0.65, 0.80)), are caused by the disease. Except for Psoriatic Arthritis and Systemic Lupus Erythematosus, we have found ≥2 food groups significantly associated with disease severity in the other IMIDs (P < 0.05). CONCLUSIONS: This cross-disease study demonstrates that prevalent IMIDs are associated to a significant change in the normal dietary patterns. This variation is highly disease-specific and, in some cases, it is caused by the disease itself. Severity in IMIDs is also associated with specific food groups. The results of this study underscore the importance of studying diet in IMIDs.

Novel association of the interleukin 2-interleukin 21 region with inflammatory bowel disease.

OBJECTIVES: Genome-wide association studies have reported the role of the interleukin (IL) 2-IL21 chromosomal region at 4q27 in several autoimmune conditions. Mice deficient in IL-2 develop a disease with clinical and histological similarity to ulcerative colitis (UC) in humans. Modest evidence of linkage with UC was tentatively proposed for the IL2 gene more than a decade ago. Therefore, we decide to investigate the association of polymorphisms in the IL-2 axis (IL2, IL2RA, and IL2RB genes) with inflammatory bowel diseases (IBDs). METHODS: Seven hundred and twenty-eight white Spanish unrelated IBD patients (356 Crohn's disease (CD) and 372 UC) and 549 ethnically matched controls were included in a case-control study. In addition, a Spanish replication cohort with 562 CD and 430 UC patients and 1,310 controls were analyzed. Eight single-nucleotide polymorphisms previously associated with different autoimmune diseases were analyzed using TaqMan chemistry. RESULTS: The IL2-rs6822844 polymorphism modified CD predisposition (P=0.002; odds ratio, OR (95% confidence interval, CI)=0.61 (0.44-0.84)); this was replicated in the other Spanish cohort, resulting in a strong protective effect of the minor allele in the merged samples (P=0.0002; OR (95% CI)=0.70 (0.58-0.85)). A similar effect of rs6822844 was detected for UC. Another marker, rs11938795, also showed evidence of an association with CD (P=0.006; OR (95% CI)=0.73 (0.58-0.92)). CONCLUSIONS: Polymorphisms within the IL2-IL21 linkage disequilibrium (LD) block show a novel association with IBD, this is concordant with suggestive previous results of whole genome analyses in CD and type 1 diabetes. Our data agree with the effect previously observed for other conditions and delineate a shared underlying mechanism.

Polymorphisms in the selenoprotein S gene: lack of association with autoimmune inflammatory diseases.

BACKGROUND: Selenoprotein S (SelS) protects the functional integrity of the endoplasmic reticulum against the deleterious effects of metabolic stress. SEPS1/SelS polymorphisms have been involved in the increased release of pro-inflammatory cytokines interleukin (IL)-1beta, tumor necrosis factor (TNF)-alpha and IL-6 in macrophages. We aimed at investigating the role of the SEPS1 variants previously associated with higher plasma levels of these cytokines and of the SEPS1 haplotypes in the susceptibility to develop immune-mediated diseases characterized by an inflammatory component. RESULTS: Six polymorphisms distributed through the SEPS1 gene (rs11327127, rs28665122, rs4965814, rs12917258, rs4965373 and rs2101171) were genotyped in more than two thousand patients suffering from type 1 diabetes, rheumatoid arthritis or inflammatory bowel diseases and 550 healthy controls included in the case-control study. CONCLUSION: Lack of association of SEPS1 polymorphisms or haplotypes precludes a major role of this gene increasing predisposition to these inflammatory diseases.

Open-label infliximab therapy in ulcerative colitis: a multicenter survey of results and predictors of response.

BACKGROUND/AIMS: Results of randomized controlled trials showing efficacy of infliximab in ulcerative colitis (UC) should be confirmed in clinical practice. We aimed to evaluate the efficacy and safety of infliximab in UC patients of the Madrid area, looking for clinical predictors of response. METHODOLOGY: Multicenter retrospective survey of all UC patients treated with infliximab in the region of Madrid (Spain). RESULTS: 47 UC patients were included (45% males, mean age 44 +/- 15 yrs), mean follow up of 4.7 months (range 0.5-21), and a total number of 211 infliximab infusions. Clinical response and steroid-free remission rates were, respectively, 97/42% in the 2nd week, 93/69% in the 6th week, and 80/65% at the long-term follow up (mean 8.2 months, range 3.5-21). Colectomy rate was 10.6% (five patients). Age, gender, disease duration, indication (steroid-resistance/dependence), disease severity, C-reactive protein, concomitant thiopurinic therapy or smoking habit did not influence on efficacy. Extent of the disease was the only predictive factor (p=0.02). Only 4 cases of mild adverse events were reported. CONCLUSIONS: Infliximab is effective and safe for UC. Real life clinical practice may have better outcome than showed in randomized controlled trials. Extent of the disease was the only predictive factor for clinical response in our experience.

[Influence of mutations of proteinase-activated receptors F2R/PAR1 and F2RL1/PAR2 on inflammatory bowel disease]. / Influencia de las mutaciones de los receptores activados por proteinasa F2R/PAR1 y F2RL1/PAR2 en la enfermedad inflamatoria intestinal.

BACKGROUND AND OBJECTIVE: Inflammatory bowel disease (IBD) is a polygenic complex trait. The expression and presence in biopsiae from IBD patients points to a putative role of these genes in genetic susceptibility to IBD. This is the first association study on these genes in relation with IBD. PATIENTS AND METHOD: Two polymorphisms were analyzed within F2R/PAR1 and another one mapping to F2RL1/PAR2 in 778 healthy controls and 943 IBD cases (Crohn's disease and ulcerative colitis patients from 2 cohorts from Madrid and Granada). RESULTS: No significant differences in the distribution of the PARs' polymorphisms were found. CONCLUSIONS: There is no evidence of association of the analyzed polymorphisms with IBD risk.

Open-label infliximab therapy in Crohn's disease: a long-term multicenter study of efficacy, safety and predictors of response.

BACKGROUND: Efficacy of infliximab in Crohn's disease (CD) showed by randomized controlled trials must be confirmed in clinical practice. We aimed to evaluate efficacy and safety of infliximab in CD patients of the Madrid area, looking for clinical predictors of response. METHODS: Multicenter retrospective survey of all CD patients treated with infliximab in 8 University hospitals of the Madrid area (Spain) with a minimum follow up of 14 wks. RESULTS: 169 patients included (48%males, mean age 39 +/- 12 yrs). 64% of them had perianal disease. 82% were under immunosuppressants. 1,355 infliximab infusions administered (mean 8, range 1-30). 90% response rate and 48% remission rate were obtained with induction therapy. 73% followed maintenance treatment, and 78% of them maintained or improved the response after a mean follow up of 28 months (range 3.5-86). 24 patients lost response during the follow up, after a mean of 41 wks (range 6-248). Only the prescription of maintenance therapy was predictive factor for favourable response (p < 0.01). 17 infusion reactions were reported (10% of the patients, 1.2% of the infusions; only one case was severe) and were the cause of treatment withdrawal in 7 patients. Co-treatment with immunosuppressive drugs and maintenance infliximab therapy were protective factors for infusion reactions (p < 0.05). Other adverse events occurred in 26% of the patients, and were cause of treatment withdrawal in 7 patients. CONCLUSIONS: Infliximab is effective and safe for CD management but concomitant immunosuppressive drugs and maintenance treatment should be prescribed to obtain the best outcome. That confirms in a real life clinical setting the favourable results obtained in randomized clinical trials.

CD209 in inflammatory bowel disease: a case-control study in the Spanish population.

BACKGROUND: The etiology of Ulcerative Colitis (UC) and Crohn's Disease (CD), considered together as Inflammatory Bowel Diseases (IBD), involves environmental and genetic factors. Although some genes are already known, the genetics underlying these diseases is complex and new candidates are continuously emerging. The CD209 gene is located in a region linked previously to IBD and a CD209 functional polymorphism (rs4804803) has been associated to other inflammatory conditions. Our aim was to study the potential involvement of this CD209 variant in IBD susceptibility. METHODS: We performed a case-control study with 515 CD patients, 497 UC patients and 731 healthy controls, all of them white Spaniards. Samples were typed for the CD209 single nucleotide polymorphism (SNP) rs4804803 by TaqMan technology. Frequency comparisons were performed using chi2 tests. RESULTS: No association between CD209 and UC or CD was observed initially. However, stratification of UC patients by HLA-DR3 status, a strong protective allele, showed that carriage of the CD209_G allele could increase susceptibility in the subgroup of HLA-DR3-positive individuals (p = 0.03 OR = 1.77 95% CI 1.04-3.02, vs. controls). CONCLUSION: A functional variant in the CD209 gene, rs4804803, does not seem to be influencing Crohn's disease susceptibility. However, it could be involved in the etiology or pathology of Ulcerative Colitis in HLA-DR3-positive individuals but further studies are necessary.

Gender-specific association of the PTPN22 C1858T polymorphism with achalasia.

The protein tyrosine phosphatase N22 (PTPN22) gene encodes a lymphoid-specific phosphatase (LYP), a downregulator of T-cell activation. Because a functional PTPN22 polymorphism, C1858T, has been found to be associated with different autoimmune diseases, we aimed to elucidate the role of this variant in predisposition to achalasia. We performed a case-control study with 231 nonrelated Spanish patients of white ethnicity diagnosed with achalasia and in 554 healthy control subjects, all genotyped for PTPN22 C1858T using TaqMan chemistry. The frequency of the 1858T allele was higher in the achalasia patients than in the healthy controls (carriers of allele T vs CC: OR = 1.38, 95% confidence interval [95% CI] 0.88-2.16, p = 0.13). Moreover a different genotype distribution was found between female and male patients (carriers of allele T vs CC: OR = 2.06, 95% CI 0.96-4.42, p = 0.04) and also between female patients and controls (OR = 1.94, 95% CI 1.12-3.36, p = 0.01), but not between male patients and controls (OR = 0.94, 95% CI 0.50-1.77, p = 0.85). We conclude that the PTPN22 1858T allele is a susceptibility factor for Spanish women with achalasia.

Genetic markers linked to rheumatoid arthritis are also strongly associated with articular manifestations in ulcerative colitis patients.

Ulcerative colitis is often accompanied by the development of extraintestinal, mainly articular, manifestations. Genetic differences could be underlying that clinical heterogeneity. We performed a case-control study to determine whether TNFab microsatellites or HLA-DR alleles were associated with the development of articular manifestations in patients with ulcerative colitis. With that aim, a total of 84 ulcerative colitis patients with articular manifestations and 172 without them were genotyped for TNFab microsatellites and HLA-DR. A healthy control sample (n = 595) was also included for comparative purposes. Haplotypes were inferred with the Arlequin software. The influence of HLA-DRB1*0103 and HLA-B27, factors previously known to be associated with extraintestinal manifestations, was specifically addressed. We observed that TNFa6b5 minihaplotype increases the susceptibility to developing articular manifestations in ulcerative colitis patients (p = 0.003, OR = 2.39). The locus HLA-DR does not appear to be involved in these extraintestinal manifestations by itself; however, the frequency of subjects carrying TNFa6b5 in combination with DR1, DR7, or DR11 is very significantly increased in patients with articular manifestations (p = 3.9 x 10(-8)). The associations found were independent of DRB1*0103 and HLA-B27. Thus, it seems that the development of articular manifestations in ulcerative colitis patients appears to be influenced by some genetic factor(s) present in some major histocompatibility complex haplotypes.

A recombined haplotype in the major histocompatibility region contains a cluster of genes conferring high susceptibility to ulcerative colitis in the Spanish population.

BACKGROUND: The most consistently described associations in ulcerative colitis (UC) have been with human leukocyte antigen (HLA) class II alleles. Our aim was to look for associations among distinct genetic polymorphisms in the major histocompatibility complex (MHC) that might play a role in determining the susceptibility to UC and especially to the extensive form of the disease. METHODS: A case-control study was performed with a total of 253 patients with UC and 315 healthy controls recruited from a single Spanish center. All the samples and 4 cell lines carrying DRB1*0103 or DRB1*1501 alleles were typed for the HLA-DRB1 class II gene and for a panel of HLA class III markers (D6S273, BAT_2, TNFa, b, c, d, e, IKBL+738, MICA). RESULTS: The frequency of the alleles DRB1*0103, IKBL+738(C) (extending our previous results) and BAT_2-8 (newly typed) was increased in patients compared with controls (P=0.00001, odds ratio [OR]=5.90; P=0.002, OR=2.42; and P=0.0001, OR=3.04, respectively), and these associations were greatest in patients with extensive disease compared with patients with distal disease (P=0.02, OR=2.53; P=0.002, OR=3.06; and P=0.03, OR=2.08, respectively). The allelic combination DRB1*0103/D6S273-5/BAT_2-8/TNFa11b4c1d3e3/IKBL+738(C)/MICA5.1 that includes the telomeric class III markers of the 7.1 ancestral haplotype is highly increased in patients with UC (P=0.0001, OR=10.57), especially in those with the extensive form of the disease (P=0.02, OR=3.41 extensive versus distal). CONCLUSIONS: The above-mentioned pattern, most likely formed by recombination of the telomeric fragment of the MHC 7.1 ancestral haplotype, seems to be the most important genetic determinant of susceptibility to the extensive form of UC in our population.

IBD5 polymorphisms in inflammatory bowel disease: association with response to infliximab.

AIM: Inflammatory bowel diseases (IBD) are multifactorial pathologies of unknown etiology. One susceptibility locus, IBD5, has been mapped to chromosome 5q31. We analyzed our Spanish cohorts of Crohn's disease (CD) and ulcerative colitis (UC) patients to determine whether this locus is associated with IBD, and to ascertain the main clinical phenotype influenced by this risk factor. The kind of interaction, either genetic heterogeneity or epistasis, between this IBD5 susceptibility region and the NOD2/CARD15 gene mutations was studied as well. Finally, we assessed whether this locus can predict response to infliximab therapy. METHODS: A case control study was performed with 274 CD and 211 UC patients recruited from a single center and 511 healthy ethnically matched controls. Two polymorphisms were genotyped in the IBD5 locus and three in the CARD15/NOD2 gene. RESULTS: Our results evidence association only with CD especially with the fistulizing phenotype and in the absence of NOD2/CARD15 variants (mutant allele frequency in patients vs controls: OR = 2.03, 95% CI = 1.35-3.06, P<0.01). The frequency of the IBD5 homozygous mutant genotype significantly increased in CD patients lacking response to infliximab (RR = 3.88, 95% CI = 1.18-12.0, P<0.05). UC patients overall do not show association with 5q31 polymorphisms, although a similar trend to the one observed in CD is found within the worse prognosis group. CONCLUSION: The IBD5 variants may enhance an individual carrier's risk for CD, mainly in the absence of the NOD2/CARD15 mutations and in fistulizing patients. The data presented suggest the potential role of the 5q31 polymorphisms as markers of response to infliximab.

[Extraintestinal manifestations in inflammatory bowel disease: differences between Crohn's disease and ulcerative colitis]. / Manifestaciones extraintestinales en la enfermedad inflamatoria intestinal: diferencias entre la enfermedad de Crohn y la colitis ulcerosa.

BACKGROUND AND OBJECTIVE: The true prevalence of the extraintestinal manifestations (EM) associated with inflammatory bowel disease (IBD) may vary depending on the geographic area, IBD population, location and duration of the disease, medication and diagnostic accuracy. The aim of this study was determine the prevalence of the major EM of IBD and their differences between Crohn's disease (CD) and ulcerative colitis (UC). PATIENTS AND METHOD: A prospective study with a total of 566 patients (295 CD with median follow up 11.6 years [range: 2-32 years] and 271 UC with median follow up 10.4 years [range: 2-36 years]. Data related to the clinical course, EM and laboratory tests were obtained at diagnosis and during follow-up. RESULTS: EM related with IBD appeared al least once in 46.6% of the patients. Joints manifestations were the most common EM. The EM were equal frequent in UC (51.5%) as in CD (42.2%). Hepatobiliary manifestations (odds ratio [OR] = 1.91; 95% confidence interval [CI] 1.15-3.16; p = 0.007), venous thromboembolism (OR = 4.26; 95% CI, 1.3-15.4; p = 0.006) and arthralgias (OR = 1.59; 95% CI, 1.01-2.5; p = 0.035) were more frequent in UC than CD. Erythema nodosum (OR = 2.35; 95% CI, 1.13-5.0; p = 0.013) and peripheral arthritis (OR = 1.95; 95% CI, 1.02-3.74; p = 0.029) were more frequent in CD. The prevalences of ocular, and the rest of joint manifestations were not different according to UC or CD. CONCLUSIONS: Prevalence of EM in Spanish IBD patients is among the highest ever reported. The distribution of the EM observed is different between CD and UC. It is necessary to know to allow to prompt diagnosis and prevent undesirable complications.

Adalimumab reversed a severe lymphopenia in a patient with Crohn's disease.

Patients with Crohn's disease are frequently found to have low peripheral lymphocyte counts. Lymphopenia has been linked to disease activity, the effects of therapy and the presence of an abnormal T regulatory (T(reg)) function. We present a patient with Crohn's disease and a severe total and CD4 lymphopenia that did not resolve after discontinuation of immunosuppressive treatment and resective surgery. Complete clinical remission and persistent normal levels of total and CD4 lymphocytes were observed after starting therapy with the anti-tumor necrosis factor monoclonal antibody adalimumab.