Fabrizio Bossa

Ulcerative colitis-risk loci on chromosomes 1p36 and 12q15 found by genome-wide association study

Ulcerative colitis is a chronic inflammatory disease of the colon that presents as diarrhea and gastrointestinal bleeding. We performed a genome-wide association study using DNA samples from 1,052 individuals with ulcerative colitis and preexisting data from 2,571 controls, all of European ancestry. In an analysis that controlled for gender and population structure, ulcerative colitis loci attaining genome-wide significance and subsequent replication in two independent populations were identified on chromosomes 1p36 (rs6426833, combined P = 5.1 × 10−13, combined odds ratio OR = 0.73) and 12q15 (rs1558744, combined P = 2.5 × 10−12, combined OR = 1.35). In addition, combined genome-wide significant evidence for association was found in a region spanning BTNL2 to HLA-DQB1 on chromosome 6p21 (rs2395185, combined P = 1.0 × 10−16, combined OR = 0.66) and at the IL23R locus on chromosome 1p31 (rs11209026, combined P = 1.3 × 10−8, combined OR = 0.56; rs10889677, combined P = 1.3 × 10−8, combined OR = 1.29).

Mongersen, an Oral SMAD7 Antisense Oligonucleotide, and Crohn’s Disease

BACKGROUND Crohns disease-related inflammation is characterized by reduced activity of the immunosuppressive cytokine transforming growth factor β1 (TGF-β1) due to high levels of SMAD7, an inhibitor of TGF-β1 signaling. Preclinical studies and a phase 1 study have shown that an oral SMAD7 antisense oligonucleotide, mongersen, targets ileal and colonic SMAD7. METHODS In a double-blind, placebo-controlled, phase 2 trial, we evaluated the efficacy of mongersen for the treatment of persons with active Crohns disease. Patients were randomly assigned to receive 10, 40, or 160 mg of mongersen or placebo per day for 2 weeks. The primary outcomes were clinical remission at day 15, defined as a Crohns Disease Activity Index (CDAI) score of less than 150, with maintenance of remission for at least 2 weeks, and the safety of mongersen treatment. A secondary outcome was clinical response (defined as a reduction of 100 points or more in the CDAI score) at day 28. RESULTS The proportions of patients who reached the primary end point were 55% and 65% for the 40-mg and 160-mg mongersen groups, respectively, as compared with 10% for the placebo group (P<0.001). There was no significant difference in the percentage of participants reaching clinical remission between the 10-mg group (12%) and the placebo group. The rate of clinical response was significantly greater among patients receiving 10 mg (37%), 40 mg (58%), or 160 mg (72%) of mongersen than among those receiving placebo (17%) (P=0.04, P<0.001, and P<0.001, respectively). Most adverse events were related to complications and symptoms of Crohns disease. CONCLUSIONS We found that study participants with Crohns disease who received mongersen had significantly higher rates of remission and clinical response than those who received placebo. (Funded by Giuliani; EudraCT number, 2011-002640-27.).

Advanced Age Is an Independent Risk Factor for Severe Infections and Mortality in Patients Given Anti–Tumor Necrosis Factor Therapy for Inflammatory Bowel Disease

BACKGROUND & AIMS Few data are available on effects of biologic therapies in patients more than 65 years old with inflammatory bowel disease (IBD). We evaluated the risk and benefits of therapy with tumor necrosis factor (TNF) inhibitors in these patients. METHODS We collected data from patients with IBD treated with infliximab (n = 2475) and adalimumab (n = 604) from 2000 to 2009 at 16 tertiary centers. Ninety-five patients (3%) were more than 65 years old (52 men; 37 with ulcerative colitis and 58 with Crohns disease; 78 treated with infliximab and 17 with adalimumab). The control group comprised 190 patients 65 years old or younger who were treated with both biologics and 190 patients older than 65 years who were treated with other drugs. The primary end points were severe infection, cancer, or death. RESULTS Among patients more than 65 years old who received infliximab and adalimumab, 11% developed severe infections, 3% developed neoplasms, and 10% died. No variable was associated with severe infection or death. Among control patients more than 65 years old, 0.5% developed severe infections, 2% developed cancer, and 2% died. Among control patients less than 65 years old, 2.6% developed severe infections, none developed tumors, and 1% died. CONCLUSIONS Patients older than 65 years treated with TNF inhibitors for IBD have a high rate of severe infections and mortality compared with younger patients or patients of the same age that did not receive these therapeutics. The effects of anti-TNF agents in older patients with IBD should be more thoroughly investigated, because these patients have higher mortality related to hospitalization than younger patients.

Combination immunomodulator and antibiotic treatment in patients with inflammatory bowel disease and clostridium difficile infection.

BACKGROUND & AIMS Management of Clostridium difficile infection in patients with flaring inflammatory bowel disease (IBD) has not been optimized. We investigated the effects of combination therapy with antibiotics and immunomodulators in patients with IBD and C difficile infection. METHODS We analyzed data from 155 patients (59% with ulcerative colitis [UC]) from a retrospective, European Crohns and Colitis organization, multi-center study comparing outcome of hospitalized IBD patients with C difficile infection who were treated with antibiotics (n = 51) or antibiotics and immunomodulators (n = 104). The primary composite outcome was death or colectomy within 3 months of admission, in-hospital megacolon, bowel perforation, hemodynamic shock, or respiratory failure. RESULTS The primary outcome occurred in 12% of patients given the combination treatment vs none of the patients given antibiotics alone (P = .01). UC, abdominal tenderness, or severe bloody diarrhea was more common among patients that received the combined therapy. However, multivariate analysis revealed that only the combination therapy maintained a trend for an independent association with the primary outcome (likelihood ratio = 11.9; CI, 0.9-157; P = .06). Treatment with 2 or 3 immunomodulators was correlated with the primary outcome, independent of disease severity at presentation (odds ratio [OR] = 17; CI, 3.2-91; P < .01). Acid-suppressing medications increased the risk of C difficile relapse (OR = 3.8; CI, 1.1-12.9; P = .03), whereas recent hospitalization correlated with increased rate of C difficile persistence (OR = 8; CI, 2.1-29; P = .002). CONCLUSIONS Patients with IBD that also have C difficile infection are frequently treated with a combination of antibiotics and immunomodulators. However, this combination tends to associate with a worse outcome than antibiotic therapy alone. Prospective controlled trials are urgently needed to optimize the management of these challenging patients.

Immunochip analyses identify a novel risk locus for primary biliary cirrhosis at 13q14, multiple independent associations at four established risk loci and epistasis between 1p31 and 7q32 risk variants

To further characterize the genetic basis of primary biliary cirrhosis (PBC), we genotyped 2426 PBC patients and 5731 unaffected controls from three independent cohorts using a single nucleotide polymorphism (SNP) array (Immunochip) enriched for autoimmune disease risk loci. Meta-analysis of the genotype data sets identified a novel disease-associated locus near the TNFSF11 gene at 13q14, provided evidence for association at six additional immune-related loci not previously implicated in PBC and confirmed associations at 19 of 22 established risk loci. Results of conditional analyses also provided evidence for multiple independent association signals at four risk loci, with haplotype analyses suggesting independent SNP effects at the 2q32 and 16p13 loci, but complex haplotype driven effects at the 3q25 and 6p21 loci. By imputing classical HLA alleles from this data set, four class II alleles independently contributing to the association signal from this region were identified. Imputation of genotypes at the non-HLA loci also provided additional associations, but none with stronger effects than the genotyped variants. An epistatic interaction between the IL12RB2 risk locus at 1p31and the IRF5 risk locus at 7q32 was also identified and suggests a complementary effect of these loci in predisposing to disease. These data expand the repertoire of genes with potential roles in PBC pathogenesis that need to be explored by follow-up biological studies.

Continuous infusion versus bolus administration of steroids in severe attacks of ulcerative colitis: a randomized, double-blind trial.

BACKGROUND:In patients with severe attacks of ulcerative colitis (UC), IV steroids represent the first-line treatment, leading to clinical improvement in approximately 50–60% of patients.AIM:The aim of this study was to prospectively compare the efficacy and safety of different modalities of steroid administration, and to evaluate predictors of failure to therapy.MATERIALS AND METHODS:In a single-center, double-blind trial, consecutive patients with a severe attack of UC received 1 mg/kg/day of 6-methyl-prednisolone administered randomly by either a bolus injection (group A) or continuous infusion (group B).RESULTS:Sixty-six patients were enrolled (35 men, mean age 38 ± 15, range 18–75 yr), 15 of them at their first attack of UC; in the remaining cases, the mean duration of disease was 4.5 ± 5 yr. At inclusion, forty patients (60%) had pancolitis and the remainder had left-sided colitis. Overall, thirty-three patients (50%) underwent clinical remission after 7 days of treatment: 16 of 32 in group A and 17 of 34 in group B. Thirty-one patients eventually underwent total colectomy (12 in group A and 9 in group B), which was carried out by the first month in 10 patients (5 in each group). Twenty-eight patients (15 in group A and 13 in group B) experienced steroid-related adverse reactions. All differences between groups were not statistically significant. Previous use of steroids (OR 13.6, CI 2–86) and active smoking (OR 11.6, CI 1.4–107) were independent predictors of nonresponse.CONCLUSIONS:In severe attacks of UC, methyl-prednisolone given as a continuous infusion was no better than bolus administration in terms of efficacy and safety.

Polymorphisms of tumor necrosis factor-α but not MDR1 influence response to medical therapy in pediatric-onset inflammatory bowel disease

Aim:We investigated the contribution of variants of tumour necrosis factor (TNF)-α and MDR1 genes in the predisposition and response to medical therapy in a large pediatric cohort of patients with Crohn disease (CD) and ulcerative colitis (UC). Patients and Methods:In this study, 200 patients with CD, 186 patients with UC, 434 parents (217 trios), and 347 healthy unrelated controls were investigated. Single-nucleotide polymorphisms −G308A and −C857T of the TNF-α gene and C3435T of the MDR1 gene were investigated and correlated with clinical subphenotypes and efficacy of medical therapy. Results:The frequency of the −308A allele of the TNF-α gene was significantly increased in both patients with CD (15%; odds ratio [OR] = 2.79; P < 0.01) and patients with UC (11%; OR = 1.96; P < 0.003) compared with controls (6%). Carriers of this allele were 27% in CD (OR = 2.94; P < 0.01) and 19% in UC (OR = 1.86; P = 0.015) compared with 11% in healthy controls. No significant difference was found for both the −C857T and C3435T single-nucleotide polymorphisms. With the genotype/phenotype analysis, no correlation in patients with UC with the MDR1 gene was found. CD carriers of the −308A allele had a higher frequency of surgical resection (35% vs 20%; OR = 2.1; P = 0.035) and more frequent resistance to steroids (22% vs 8%; OR = 0.29; P = 0.032) compared with noncarriers. These findings were confirmed by stepwise logistic regression. Conclusions:In our pediatric cohort, the promoter −308A polymorphism of TNF-α but not the MDR1 gene is significantly involved in the predisposition to both CD and UC. This polymorphism carries a significant reduction in response to steroid therapy, probably leading to a more frequent need for surgical resection.

Variants of OCTN1-2 cation transporter genes are associated with both Crohn's disease and ulcerative colitis

Background  Two variants in the organic cation transporter gene cluster have been recently reported to confer susceptibility to Crohns disease (CD).

Multidrug resistance 1 gene polymorphisms are not associated with inflammatory bowel disease and response to therapy in Italian patients

Background : Host genetic factors may be important in determining not only disease susceptibility, but also disease behaviour and response to therapy in inflammatory bowel disease. Two polymorphisms (C3435T and G2677T/A) of the multidrug resistance 1 gene have been correlated with the altered P‐glycoprotein expression and function in humans, and associated with predisposition to ulcerative colitis and Crohns disease.

Erythrocyte-Mediated Delivery of Dexamethasone in Patients With Mild-to-Moderate Ulcerative Colitis, Refractory to Mesalamine: A Randomized, Controlled Study

BACKGROUND AND AIM:Nearly 25% of patients with ulcerative colitis (UC) requiring steroids therapy become steroid-dependent after 1 yr, and virtually all develop steroid-related adverse events. We planned a controlled study to investigate the efficacy and safety of dexamethasone 21-P (Dex 21-P) encapsulated into erythrocytes (DEE).MATERIALS AND METHODS: Forty patients with mild-to-moderate UC, refractory to mesalamine, were randomly assigned to one of the following three treatments: two DEE infusions 14 days apart (group A, N = 20), oral prednisolone (0.5 mg/kg for 14 days followed by a 6 mg/weekly tapering (group B, N = 10), and sham infusions (group C, N = 10). The clinical, biochemical, and endoscopic parameters were monitored at inclusion and after 8 wk.RESULTS:In group A, a mean dose of 9.9 ± 4.1 mg Dex 21-P was loaded into autologous erythrocytes at each infusion. At 8 wk, 15 patients in group A (75%), 8 in group B (80%), and 1 in group C (10%, P < 0.001 vs A and B) were in clinical and endoscopic remission. When compared with the baseline values, C-reactive protein (CRP) dropped in groups A (1.6 mg/dL vs 0.4 mg/dL, P= 0.006) and B (1.0 vs 0.5, P= 0.02), but not in group C. No steroid-related adverse events were apparent in the patient treated with DEE, compared with 8 out of 10 patients on oral steroids (P≤ 0.01).CONCLUSION:Low doses of Dex (mean total dose ± 20 mg) loaded into autologous erythrocytes were significantly more effective than sham infusions in terms of symptoms relief, endoscopic, and biochemical improvements in UC patients refractory to mesalamine. In addition, in contrast to oral prednisolone (mean total dose ± 1 g), no steroid-related adverse events were induced.