The CTLA4 variants may interact with the IL23R- and NOD2-conferred risk in development of Crohn's disease

<p>Abstract</p> <p>Background</p> <p>The <it>CTLA4 </it>(cytotoxic T-lymphocyte antigen 4) gene is associated with several immunopathologic diseases and because of its important immuno-regulatory role it may be considered also a plausible candidate for a genetic association with inflammatory bowel diseases. Previously published studies found no association of <it>CTLA4 </it>with Crohn's disease itself, but some indicated an association with its subphenotypes. The aim of this study was to assess the association in the Czech population, using a set of markers shown to associate with other diseases.</p> <p>Methods</p> <p>Six polymorphisms within the <it>CTLA4 </it>region were investigated in 333 patients with Crohn's disease and 482 unrelated healthy controls, all Caucasians of Czech origin. The genotypes of the SNPs were determined using the TaqMan SNP genotyping assays. Haplotypes were reconstructed using an expectation-maximization algorithm, and their association with the condition was assessed using log-linear modeling. Then, potential interactions were tested between the <it>CTLA4 </it>variants and other genetic factors known to confer the disease susceptibility.</p> <p>Results</p> <p>No crude associations with Crohn's disease were found for the tested <it>CTLA4 </it>variants under the log-additive or dominant models. However, when stratified for the genetic risk conferred by the variants in the <it>NOD2 </it>(the p.Leu1007fsX1008, rs5743293) or the <it>IL23R </it>(p.R381Q, rs11209026), a significant negative association emerged for the minor alleles of <it>CTLA4 </it>CT60 (rs3087243), JO31 (rs11571302), JO27-1 (rs11571297) polymorphisms. This negative association with <it>CTLA4 </it>was apparent only in the strata defined by presence minor alleles at the <it>NOD2 </it>rs5743293 (here the <it>CTLA4 </it>CT60 A coffered an OR = 0.43, 95%CI 0.19 - 0.95 for the presence of CT60 A), or <it>IL23R </it>rs11209026 (here the OR for presence of CT60 A was 0.23, 95%CI 0.07 - 0.71). We observed this effect also for the haplotype consisting of minor alleles of the three tightly linked <it>CTLA4 </it>markers. Furthermore, this haplotype was associated with the younger age at diagnosis (OR 1.52, 95%CI 1.09 - 2.11, p = 0.014).</p> <p>Conclusions</p> <p>A protective effect of a <it>CTLA4 </it>haplotype was unmasked after stratification for the risk variants in the <it>NOD2 </it>and <it>IL23R </it>genes, and may point towards the biological relevance of the molecule in the pathogenesis of the disease.</p

Prediction of thiopurine failure in pediatric Crohns disease bpediatric IBD Porto group of ESPGHAN$

Background: Maintaining of remission early in the disease course of Crohn’s disease (CD) is essential and has major impact on the future prognosis. This study aimed to identify baseline predictors to develop model allowing stratification of patients who will not benefit from long-term azathioprine (AZA) treatment and will require more intensive therapy. Methods: This study was designed to develop clinical prediction rule using retrospective data analysis of pediatric CD patients included in prospective inception cohort. Clinical relapse was defined as necessity of re-induction of remission. Sequence of Cox models was fitted to predict risk of relapse. Results: Out of 1190 CD patients from 13 European centers, 441 were included, 50.3% patients did not experience clinical relapse within 2 years of AZA treatment initiation. Median time to relapse was 2.11 (CI 1.59–2.46) years. Of all the tested parameters available at diagnosis, six were significant in multivariate analyses: C-reactive protein (p = 0.038), body mass index Z-score >0.8 SD (p = 0.002), abnormal sigmoid imaging (p = 0.039), abnormal esophageal endoscopy (p = 0.005), ileocolonic localization (p = 0.023), AZA dose in specific age category (p = 0.031). Conclusions: Although the possibility of predicting relapse on AZA treatment appears limited, we developed predictive model based on six baseline parameters potentially helpful in clinical decision. Impact: The possibility of predicting relapse on AZA treatment appears to be possible but limited.We identified six independent predictors available at diagnosis of early AZA/6-MP treatment failure in pediatric CD patients.Using combination of these factors, a model applicable to clinical practice was created.A web-based tool, allowing estimation of individual relapse risk in pediatric CD patients on a particular therapeutic regimen, has been developed

Safety and Potential Efficacy of Escalating Dose of Ustekinumab in Pediatric Crohn Disease (the Speed-up Study): A Multicenter Study from the Pediatric IBD Porto Group of ESPGHAN

OBJECTIVES: Escalation of the ustekinumab (UST) maintenance dosage was effective in adults with Crohn disease (CD), but no data are available for children. We evaluated the effectiveness and safety of dose escalation of UST in pediatric CD. METHODS: This was a retrospective multicenter study from 25 centers affiliated with the IBD Interest and Porto groups of ESPGHAN. We included children with CD who initiated UST at a standard dosing and underwent either dose escalation to intervals shorter than 8 weeks or re-induction of UST due to active disease. Demographic, clinical, laboratory, endoscopic, imaging, and safety data were collected up to 12 months of follow-up. RESULTS: Sixty-nine children were included (median age 15.8 years, interquartile range 13.8-16.9) with median disease duration of 4.3 years (2.9-6.3). Most children were biologic (98.6%)- and immunomodulator (86.8%)- experienced. Clinical response and remission were observed at 3 months after UST escalation in 46 (67%) and 29 (42%) children, respectively. The strongest predictor for clinical remission was lower weighted Pediatric Crohn Disease Activity Index (wPCDAI) at escalation ( P = 0.001). The median C-reactive protein level decreased from 14 (3-28.03) to 5 (1.1-20.5) mg/L ( P = 0.012), and the fecal calprotectin level from 1100 (500-2300) to 515 (250-1469) µg/g ( P = 0.012) 3 months post-escalation. Endoscopic and transmural healing were achieved in 3 of 19 (16%) and 2 of 15 (13%) patients, respectively. Thirteen patients (18.8%) discontinued therapy due to active disease. No serious adverse events were reported. CONCLUSIONS: Two-thirds of children with active CD responded to dose escalation of UST. Milder disease activity may predict a favorable outcome following UST dose escalation