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Biomedical subjects

Séverine Vermeire

Publications and source records attributed to Séverine Vermeire.

At least 19 recordsLinked to original sources
PubMed2007

Predictors of early response to infliximab in patients with ulcerative colitis.

BACKGROUND: Our objective is to report the outcome of infliximab (IFX) in ulcerative colitis (UC) patients from a single center and to identify predictors of early clinical response. METHODS: The first 100 UC patients (45 female; median age, 37.9 years) who received IFX at a single center were included. Eighty-four patients received 5 mg/kg IFX, and 37 patients received a 3-dose IFX induction at weeks 0, 2, and 6. The Mayo endoscopic subscore, assessed by sigmoidoscopy before inclusion, was 1, 2, and 3 in 5%, 52%, and 43% of patients, respectively. Sixty percent had pancolitis, 63% were on concomitant immunosuppressive therapy, 9% were active smokers, 64% had C-reactive protein > or =5 mg/dL, and 44% were pANCA+/ASCA-. Five patients received IFX because of severe acute colitis refractory to intravenous corticosteroids. RESULTS: Early complete and partial clinical responses were observed in 41% and 24% of patients. Patients with early clinical response were significantly younger than nonresponders (median age, 35.7 versus 41.6 years, P = 0.041). Patients who were pANCA+/ASCA- had a significantly lower early clinical response (55% versus 76%; odds ratio [OR] = 0.40 (0.16-0.99), P = 0.049). Concomitant immunosuppressive therapy and the use of an IFX induction scheme did not influence early clinical response. Only 1 of 5 patients who received IFX for acute steroid-refractory colitis required colectomy within 2 months. CONCLUSIONS: IFX is an efficient therapy in UC, as shown by 65% early clinical response. A pANCA+/ASCA- serotype and an older age at first IFX infusion are associated with a suboptimal early clinical response.

Adolescent↗
PubMed2007

NOD2/CARD15 disease associations other than Crohn's disease.

At this moment, few confirmed associations between NOD2 mutations and diseases other than Crohn's disease (CD) and Blau syndrome (BS) have been reported, but research is ongoing in several fields where a genetic susceptibility factor and/or a role for the innate immune system is suspected. Whether the Crohn's-associated CARD15 mutations lead to a loss or gain of function of the NOD2 receptor is subject to controversy, and by which mechanisms this change in function might increase the susceptibility to CD is still under investigation. The possible involvement of NOD2/CARD15 in the pathogenesis of certain diseases with already (partially) unraveled pathophysiologic mechanisms might contribute to our further understanding of NOD2/CARD15 and its function in CD. We review studies on the association of CARD15 variants with diseases other than CD. The association of NOD2/CARD15 mutations with CD and BS, and possibly also early onset sarcoidosis, suggests a role for the gene in the development of granulomata and granulomatous diseases, possibly by inappropriate activation of the immune system. The data from the oncology field suggest that this inappropriate activation might even lead to uncontrolled proliferation of certain cell types. The studies in allergic diseases and atopy are the largest so far, and the association of NOD2/CARDI5 mutations with atopic phenotypes might be an indication that CARD15 also plays a role in the Th2 pathway. Finally, transplantation studies indicate that the genetic background of a patient should be taken into account when considering hematopoietic stem cell transplantation, given the increased risk of mortality and graft versus host disease observed. Whether NOD2 variants are also associated with an increased risk for infections and sepsis in patients receiving immunosuppressive therapies is unclear.

Arthrobacter↗
PubMed2007

Contribution of genetic and environmental factors in the pathogenesis of Crohn's disease in a large family with multiple cases.

BACKGROUND: A large family of Moroccan immigrants was investigated. In this family the father developed Crohn's disease (CD) after moving from Morocco to Belgium and successively 4 of his 8 children subsequently developed CD. There was no previous history of familial CD. METHODS: The family was interviewed at their home and an elaborated questionnaire was completed. The food and sanitation characteristics of the family were investigated. Moreover, serological markers were tested in all family members, including ASCA, ASCAg, ALCA, ACCA, Omp, and ANCA, using enzyme-linked immunosorbent assay and indirect immunofluorescence. Genetic variants in CARD15, TLR4, NOD1, CARD8, and DLG5 associated with CD were tested as well. The complete medical history of all patients was reviewed. RESULTS: There were no known genetic variants associated with CD in this family. None of the serological antibodies could discriminate between patients and unaffected family members, although the antibody titers were higher in diseased family members as compared with the healthy family members. CONCLUSION: The occurrence of 5 new cases of CD within 1 Moroccan family after immigration to Belgium cannot be explained by the known genetic susceptibility factors, and thus suggests a major environmental factor probably not related to sanitation in childhood.

Adolescent↗
PubMed2006

Focus on mechanisms of inflammation in inflammatory bowel disease sites of inhibition: current and future therapies.

Anti-TNF antibodies were the first biologic agents registered to treat patients who have CD and, more recently, patients who have UC. The sequence of events underlying the inflammatory reaction in IBD is extremely complex, however, and involves both the innate and antigen-driven adaptive immune system. Novel therapies are directed at several key players of this cascade. Blockade of T-cell proliferation and activation and inhibition of T-cell cytokines has been most extensively targeted by clinical trials in humans. Inhibition of adhesion molecules and the use of selected growth factors seem to have therapeutic potential. Restoration of regulatory T-cell and dendritic-cell function is still waiting to be explored in clinical trials. Although an increasing number of biologic therapies for IBD are being developed, the discovery of the full spectrum of treatment modalities is only beginning. Often, however, the clinical efficacy of biologic agents is investigated, and for some molecules is established, before mechanisms of action are specifically explored. Eight years after the Food and Drug Administration approved infliximab for the treatment of luminal CD, it is not known how this anti-TNF antibody actually dampens inflammation in IBD. The advent of newer anti-TNF agents is only postponing the answer.

Anti-Inflammatory Agents↗
PubMed2006

The value of myenteric plexitis to predict early postoperative Crohn's disease recurrence.

BACKGROUND & AIMS: Early ileocolonoscopy allows detection of recurrence after surgically induced remission of Crohn's disease (CD). Unequivocal histologic markers predicting recurrence have not been identified. We assessed the predictive value of neural lesions for early endoscopic CD recurrence and long-term reintervention risk. METHODS: Ileocolonic resection specimens from 59 patients with CD and 21 control patients were histologically scored for typical inflammatory bowel disease lesions, neural hypertrophy, and presence and severity of inflamed ganglia and nerve bundles. Endoscopic recurrence was determined at 3 months in all patients and at 1 year in 32 patients as part of 2 prospective clinical trials. RESULTS: Myenteric plexitis of the proximal resection margin was present in 32 patients with CD (54%) in absence of surrounding inflammation. Patients with this feature had a higher endoscopic recurrence (Rutgeerts score >/=2) at 3 months (75% vs 41%; odds ratio, 4.36; 95% confidence interval, 1.44-13.23; P = .008) and at 1 year (93% vs 59%; odds ratio, 9.80; 95% confidence interval, 1.04-92.70; P = .041) and had a trend toward an earlier reintervention (mean, 7.00 vs 5.30 years; P = .174). The severity of myenteric plexitis in the proximal resection margin correlated with the severity of endoscopic recurrence at 3 months (r = 0.334, P = .010) and 1 year (r = 0.560, P = .001). Myenteric plexitis was the only consistent predictor of endoscopic recurrence. CONCLUSIONS: The presence of myenteric plexitis in proximal margins of ileocolonic resection specimens is predictive of early endoscopic CD recurrence.

Anastomosis, Surgical↗
PubMed2006

Lymphotoxin alpha gene in Crohn's disease patients: absence of implication in the response to infliximab in a large cohort study.

A haplotype in the lymphotoxin alpha (LTA) gene has been associated with a lack of response to infliximab in a small cohort of Crohn's disease (CD) patients. The present study aimed to confirm the implication of this haplotype in the response to infliximab in a larger cohort of Caucasian patients. The response to the first infusion with infliximab was evaluated in 214 Caucasian patients with either luminal (n=150) or fistulising (n=64) CD. Clinical response was based on the decrease in CD Activity Index (luminal) or on the evolution in the fistula discharge (fistulising). Biological response was assessed in 139 patients who had elevated C-reactive protein (CRP) before treatment and for whom CRP values were also available after treatment. A positive biological response was defined as a decrease in CRP of at least 25%. The patients were genotyped for six polymorphisms in the LTA gene. A positive clinical response was present in 65.4% of the patients and a positive biological response was observed in 80.6% of the patients. No association was found with any of the studied polymorphisms, nor with the previously published LTA haplotype and the response to infliximab. We could not confirm an association between the LTA locus and clinical or biological response to infliximab in a large cohort of CD patients.

Adult↗
PubMed2006

The TNF/ADAM 17 system: implication of an ADAM 17 haplotype in the clinical response to infliximab in Crohn's disease.

Infliximab, a chimeric anti-tumour necrosis factor (TNF)-alpha antibody induces a clinical response in 70% of Crohn's disease patients and the response to infliximab therapy could be partially determined by genetic factors. The implication of both transmembrane and soluble forms of the TNF-alpha in the mechanism of action of infliximab has been demonstrated. The aim of our work was first to perform a complete study of TNF variants role in the response to infliximab in Crohn's disease. Secondly, considering the role of ADAM 17 in TNF-alpha shedding, the ADAM 17 locus was also studied. The response to infliximab was evaluated in 222 Caucasian Crohn's disease patients with a luminal (n=160) or fistulizing (n=62) form of the disease. Clinical and biological response evaluation was based on the Crohn's Disease Activity Index score and C-reactive protein level evolutions, respectively. The entire TNF gene was sequenced on the complete cohort. Twelve single nucleotide polymorphisms spanning the ADAM 17 locus were studied and haplotypes rebuilt. A clinical response was observed in 64% of the patients and biological response in 77.1% of patients. No association was found between the TNF gene and the response to infliximab. One haplotype in the ADAM 17 region was associated with a clinical response to infliximab in CD patients (adjusted P=0.045). In conclusion, our results exclude, with a reasonable power, an implication of the TNF gene in the response to infliximab in Crohn's disease, but reveal a potential role of the ADAM 17 gene in this response.

ADAM Proteins↗
PubMed2006

CC-type chemokine receptor 5-Delta32 mutation protects against primary sclerosing cholangitis.

BACKGROUND: Primary sclerosing cholangitis (PSC) is commonly associated with inflammatory bowel disease (IBD) and characterized by fibrosing inflammatory destruction of biliary ducts. The pathogenesis of PSC remains unknown, but immunological, bacterial, viral, and toxic factors play a role in a genetically susceptible host. We hypothesized that CC-type chemokine receptor 5 (CCR5) would be an interesting candidate gene for susceptibility to PSC from its chromosomal location within the IBD susceptibility locus on 3p21, as well as from a functional perspective. We therefore investigated the role of the functional 32-bp deletion in this gene (CCR5-Delta32) with regard to susceptibility to PSC. METHODS: A total of 110 patients with PSC, 56 with concomitant IBD (23 with Crohn's disease, 28 with ulcerative colitis, 5 with indeterminate colitis), were collected. All of the subjects were genotyped for CCR5-Delta32 with polymerase chain reaction amplification, followed by detection on ethidium bromide-stained agarose gel. Genotypes and allele frequencies were compared with a cohort of IBD patients without PSC (n = 400) and healthy control subjects (n = 362). RESULTS: The frequency of the CCR5-Delta32 mutation in PSC (6.8%) was significantly lower compared with IBD (12.6%; P = 0.016) and healthy control subjects (12.2%, P = 0.026), suggesting a protective effect of this mutation on PSC. None of the PSC patients with severe disease necessitating liver transplantation (n = 17) carried CCR5-Delta32. CONCLUSIONS: Because an intact CCR5 receptor is needed for internalization of specific pathogens and homing of memory T lymphocytes to the liver, we hypothesize that a deficient expression of this receptor resulting from the CCR5-Delta32 variant may protect against PSC.

Adolescent↗
PubMed2006

Safety issues with biological therapies for inflammatory bowel disease.

PURPOSE OF REVIEW: The purpose of this review is to summarize recent evidence describing specific complications associated with the use of biological therapy derived from controlled trials and from post-marketing surveillance. RECENT FINDINGS: Biological therapies, particularly anti-tumour necrosis factor antibodies, are increasingly used in patients with Crohn's disease and ulcerative colitis. Some adverse events, such as serious infections, are a consequence of the immunomodulatory effect of biological agents, while other complications, such as the induction of autoimmune phenomena, neurotoxicity and the development of an immune response to engineered proteins, are class or molecule-specific. Although the immunopathogenesis of these side effects is often a matter of debate, they have been observed not only in inflammatory bowel disease, but also in other immune disorders such as rheumatoid arthritis and psoriasis. SUMMARY: The benefits of biological agents clearly outweigh the risks. Nevertheless, they are associated with specific toxicity, and this requires the attention of the clinician.

Antibodies, Monoclonal↗
PubMed2006

Emerging biological treatments in inflammatory bowel diseases.

Although the advent of infliximab has changed the treatment paradigm and goals in inflammatory bowel disease, it does not provide a cure for it and recent evidence has demonstrated that the immunogenicity of this chimeric anti-tumor necrosis factor antibody is associated with secondary loss of response and intolerance. In ulcerative colitis the efficacy of infliximab was demonstrated in two large clinical trials, but long-term maintenance efficacy data are lacking. Novel biological agents have entered clinical development and pioneering trials have been reported in the last 2 years. For Crohn's disease the fully human IgG1 anti-tumor necrosis factor monoclonal adalimumab, and the humanized anti-alpha4-integrin IgG4 antibody, natalizumab have yielded the most promising results in controlled trials, but also agents inhibiting the crucial interleukin-12/interferon-gamma feedback loop suggest therapeutic potential. For severe ulcerative colitis infliximab has been shown to be an effective rescue treatment and the anti-T-cell CD3 antibody has shown promising open-label results. Crucial in the development of novel biological agents, however, is the benefit:risk ratio. As illustrated by unexpected but devastating brain infections with anti-adhesion molecules, clinicians should be aware that the powerful immunomodulatory capacity of biologicals necessitates a rigorous safety follow-up.

Antibodies, Monoclonal↗
PubMed2005

Progressive multifocal leukoencephalopathy after natalizumab therapy for Crohn's disease.

The prior diagnosis of fatal astrocytoma in a 60-year-old man with Crohn's disease treated with natalizumab, a monoclonal antibody against alpha4 integrins, was reclassified as JC virus-related progressive multifocal leukoencephalopathy (PML). Analysis of frozen serum samples showed that JC virus DNA had appeared in the serum three months after the initiation of open-label natalizumab monotherapy and two months before the appearance of symptomatic PML. There was staining of the brain lesion for polyomavirus. This case report, along with two others, suggests that anti-alpha4-integrin therapy can result in JC virus-induced PML.

Antibodies, Monoclonal↗
PubMed2005

The role of C-reactive protein as an inflammatory marker in gastrointestinal diseases.

C-reactive protein (CRP) is an acute-phase protein that is produced in large amounts by hepatocytes, upon stimulation by the cytokines interleukin-6, tumor-necrosis-factor-alpha and interleukin-1beta, during an acute-phase response. CRP is an objective marker of inflammation and, in gastrointestinal diseases such as Crohn's disease and acute pancreatitis, its levels correlate well with clinical disease activity. In contrast to its use as a marker in Crohn's disease, however, CRP is a less reliable marker of inflammation and disease activity in patients with ulcerative colitis, except perhaps for severe, extensive colitis. The increased production of CRP after an acute-phase stimulus, such as active gut inflammation, might explain why strong anti-inflammatory agents, such as anti-tumor-necrosis-factor-alpha antibodies and other biologic agents, work particularly well in patients with increased levels of CRP. CRP is also useful as a laboratory marker to predict prognosis and relapse in patients with Crohn's disease and acute pancreatitis. Elevated CRP levels have been associated with an increased risk of colorectal cancer and are a marker of poor prognosis, indicating more advanced disease and, possibly, reduced survival. An important question that remains is how often CRP levels should be measured. Until there are more data, the use of CRP and of other biomarkers should be seen as an additional tool that aids clinical observation and physical examination, but that cannot replace it.

Biomarkers↗
PubMed2005

Ornidazole for prophylaxis of postoperative Crohn's disease recurrence: a randomized, double-blind, placebo-controlled trial.

BACKGROUND & AIMS: Crohn's disease almost inevitably recurs after ileocolonic resection, and effective prophylactic therapy has not been identified. We investigated the efficacy and safety of ornidazole, a nitroimidazole antibiotic, for the prevention of clinical recurrence of Crohn's disease after curative ileocolonic resection in a placebo-controlled double-blind clinical trial. METHODS: Eighty patients were randomized to ornidazole 1 g/day or placebo started within 1 week of resection and continued for 1 year. The primary end point was the proportion of patients with clinical recurrence at 1 year. Secondary end points were endoscopic recurrence at 3 months and 12 months after resection. RESULTS: Two patients in the ornidazole group withdrew consent and were not dosed. Ornidazole significantly reduced the clinical recurrence rate at 1 year from 15 of 40 (37.5%) patients in the placebo group to 3 of 38 (7.9%) patients in the ornidazole group (Fisher exact test, 8.03; P = .0046; odds ratio, 0.14; 95% confidence interval, 0.037-0.546). Ornidazole reduced endoscopic recurrence at 12 months from 26 of 33 (79%) in the placebo group to 15 of 28 (53.6%) in the ornidazole group (chi2 , 4.37; P = .037; odds ratio, 0.31; 95% confidence interval, 0.10-0.94). Endoscopic recurrence at 3 and 12 months predicted clinical recurrence. Significantly more patients in the ornidazole group dropped out from the study because of side effects (P = .041). CONCLUSIONS: Ornidazole 1 g/day is effective for the prevention of recurrence of Crohn's disease after ileocolonic resection.

Adult↗
PubMed2005

Association of organic cation transporter risk haplotype with perianal penetrating Crohn's disease but not with susceptibility to IBD.

BACKGROUND & AIMS: Three years after the identification of NOD2/CARD15, 2 more genes for inflammatory bowel diseases (IBDs) were reported. The carnitine/organic cation transporter (OCTN) on 5q31 (IBD5) is associated with Crohn's disease (CD) and DLG5 (10q23), a member of membrane-associated guanylate kinase (MAGUK) family, with IBD. We studied mutation prevalence, assessed phenotypic expression, and performed conditional analysis to examine evidence for gene-gene interactions. METHODS: A cohort of 2032 individuals was genotyped for disease-associated OCTN and DLG5 variants, including 981 patients with IBD (CD, n = 769; ulcerative colitis, n = 186; indeterminate colitis, n = 26) followed up at a tertiary IBD center. For 373 patients, DNA from both parents was available (cohort 1) for transmission disequilibrium testing analysis; case-control analysis was performed in 608 patients and 305 controls (cohort 2). RESULTS: There was no distortion of transmission toward affected offspring for any of the variant alleles. Case-control analysis also failed to shown an association. A higher frequency of DLG5 113A was observed in CARD15-positive patients (12.2%) compared with CARD15-negative patients (8.7%; P = .033). The OCTN-TC risk haplotype was associated with penetrating disease (odds ratio, 1.474; 95% confidence interval, 1.028-2.114; P = .035). For DLG5, there were no associations with a particular phenotype. CONCLUSIONS: DLG5 and OCTN do not play a role in the susceptibility to IBD, CD, or ulcerative colitis in the Flemish population but play a role in the phenotypic expression of the disease. OCTN variants were associated with perianal and penetrating CD. More studies in independent populations are urgently needed to assess the validity of DLG5 and OCTN in the pathogenesis of IBD.

Adolescent↗
PubMed2005

Medical treatment of inflammatory bowel diseases.

PURPOSE OF REVIEW: Despite the advent of the anti-TNF agent, infliximab, an important unmet medical need characterizes the medical treatment of inflammatory bowel diseases. This review aims to summarize recent progress in the field. RECENT FINDINGS: For Crohn's disease, the fully human IgG1 anti-TNF monoclonal antibody, adalimumab and the humanized anti-alpha4 integrin IgG4 antibody, natalizumab have yielded the most promising results in controlled trials, but agents inhibiting the crucial IL12/interferon-gamma feedback loop also suggest therapeutic potential. Maintenance treatment with azathioprine, although efficacious, is not tolerated by up to 25% of individuals, but 6-thioguanine, an active metabolite, is associated with liver toxicity and is no longer recommended. For severe ulcerative colitis, low intravenous cyclosporine doses have been demonstrated to be efficacious, and may serve to limit the toxicity with this agent. Biologic treatment is being developed to target severe ulcerative colitis. Efficacy of infliximab to stop fistula draining as a maintenance agent for fistulizing Crohn's disease has been demonstrated in a large controlled trial, but MRI imaging indicates that the improvement of inflammation in fistula tracks is delayed. SUMMARY: In conclusion, medical therapy of inflammatory bowel diseases is a constantly moving field and recent evolutions will undoubtedly change clinical practice in the years to come.

Antibodies, Monoclonal↗
PubMed2004

Optimizing anti-TNF treatment in inflammatory bowel disease.

Infliximab, the chimeric monoclonal immunoglobulin (Ig)G1 antibody to tumor necrosis factor (TNF) has changed our therapy of Crohn's disease. Infliximab is indicated in refractory luminal and fistulizing Crohn's disease. In patients with luminal disease, a single intravenous (i.v.) dose of 5 mg/kg is efficacious; in fistulizing disease, an i.v. loading therapy of 5 mg/kg at weeks 0, 2, and 6 is advocated. Because the majority of patients will relapse if not re-treated, a long-term strategy is necessary. The optimal long-term approach is systematic re-treatment with 5 mg/kg every 8 weeks. Episodic therapy on relapse also is possible but is less efficacious and frequently is associated with problems resulting from the formation of antibodies to infliximab (ATI). If treatment is episodic, maintenance therapy with immunosuppression (azathioprine [AZA]/6-mercaptopurine [6-MP] or methotrexate) is mandatory. Trial data suggest that systematic maintenance with 8 weekly doses of infliximab decreases the rate of complications, hospitalizations, and surgeries. These effects probably are achieved thanks to thorough healing of the bowel. Infliximab also is indicated in treating corticosteroid-dependent Crohn's disease and extraintestinal manifestations of Crohn's disease. There are no data yet that support its use as first-line therapy. The data in ulcerative colitis (UC) are conflicting and we should await the results of 2 large controlled trials (ACT1 and ACT2) to position infliximab in the treatment of UC. Other anti-TNF strategies have been less effective than infliximab in the treatment of IBD until now. The results with thalidomide are promising but much more research into small molecules inhibiting TNF and other proinflammatory cytokines is necessary. Safety problems with antibody treatment mainly concern immunogenicity leading to infusion reactions, loss of response, and serum sickness-like delayed infusion reactions. The rate of opportunistic infections is increased mainly in patients treated concomitantly with immunosuppression. Other adverse events associated with anti-TNF strategies are demyelinating disease and worsening of congestive heart failure. Malignancy rates in patients treated with anti-TNF strategies do not seem to be increased.

Adalimumab↗