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Featured researches published by Marc Lemann.


Nature Genetics | 2010

Genome-wide meta-analysis increases to 71 the number of confirmed Crohn's disease susceptibility loci

Andre Franke; Dermot McGovern; Jeffrey C. Barrett; Kai Wang; Graham L. Radford-Smith; Tariq Ahmad; Charlie W. Lees; Tobias Balschun; James C. Lee; Rebecca L. Roberts; Carl A. Anderson; Joshua C. Bis; Suzanne Bumpstead; David Ellinghaus; Eleonora M. Festen; Michel Georges; Todd Green; Talin Haritunians; Luke Jostins; Anna Latiano; Christopher G. Mathew; Grant W. Montgomery; Natalie J. Prescott; Soumya Raychaudhuri; Jerome I. Rotter; Philip Schumm; Yashoda Sharma; Lisa A. Simms; Kent D. Taylor; David C. Whiteman

We undertook a meta-analysis of six Crohns disease genome-wide association studies (GWAS) comprising 6,333 affected individuals (cases) and 15,056 controls and followed up the top association signals in 15,694 cases, 14,026 controls and 414 parent-offspring trios. We identified 30 new susceptibility loci meeting genome-wide significance (P < 5 × 10−8). A series of in silico analyses highlighted particular genes within these loci and, together with manual curation, implicated functionally interesting candidate genes including SMAD3, ERAP2, IL10, IL2RA, TYK2, FUT2, DNMT3A, DENND1B, BACH2 and TAGAP. Combined with previously confirmed loci, these results identify 71 distinct loci with genome-wide significant evidence for association with Crohns disease.


Journal of Crohns & Colitis | 2010

The second European evidence-based Consensus on the diagnosis and management of Crohn's disease: Current management

A. Dignass; G. Van Assche; Marc Lemann; Johan D. Söderholm; S. Danese; André D'Hoore; Miquel A. Gassull; Fernando Gomollón; Pierre Michetti; Colm O'Morain; T. Öresland; Alastair Windsor

This paper is the second in a series of three publications relating to the European evidence-based consensus on the diagnosis and management of Crohns disease and concerns the management of active disease, maintenance of medically induced remission and surgery. The aims and methods of the ECCO Consensus, as well as sections on diagnosis and classification are covered in the first paper [van Assche et al. JCC 2009a]. The final paper covers post-operative recurrence, fistulating disease, the management of paediatric and adolescent IBD, pregnancy, psychosomatics, extraintestinal manifestations and complementary or alternative therapy for Crohns disease [Van Assche et al JCC 2009b]. #### Principal changes with respect to the 2006 ECCO guidelines The early use of azathioprine/mercaptopurine or methotrexate in combination with steroids is an appropriate option in moderately active localised ileocaecal CD. Anti-TNF therapy should be considered as an alternative for patients with objective evidence of active disease who have previously been steroid-refractory, steroid-dependent, or steroid-intolerant (based on Statement 5B). For those patients with severely active localised ileocaecal Crohns disease and objective evidence of active disease who have relapsed, anti-TNF therapy with or without an immunomodulator is an appropriate option [EL1a, RG B for infliximab]. For some patients who have infrequently relapsing disease, restarting steroids with an immunomodulator may be appropriate (based on Statement 5C). All currently available anti-TNF therapies appear to have generally similar efficacy and adverse-event profiles for inflammatory (‘luminal’) Crohns disease, so the choice depends on availability, route of delivery, patient preference, cost and national guidelines \[EL5, RG D\] (Statement 5I). Patients receiving azathioprine or mercaptopurine who relapse should be evaluated for adherence to therapy and have their dose optimised. Changing their maintenance therapy to methotrexate [EL1b RG B] or anti-TNF therapy [EL1a RGB] should be considered. Surgery should always be considered as an option in localised disease [EL4, …


The Lancet | 2009

Lymphoproliferative disorders in patients receiving thiopurines for inflammatory bowel disease: a prospective observational cohort study

Laurent Beaugerie; Nicole Brousse; Anne Marie Bouvier; Jean-Frederic Colombel; Marc Lemann; Jacques Cosnes; Xavier Hébuterne; Antoine Cortot; Yoram Bouhnik; Jean Pierre Gendre; Tabassome Simon; Marc Maynadié; Olivier Hermine; Jean Faivre; Fabrice Carrat

BACKGROUND Reports of an increased risk of lymphoproliferative disorders in patients receiving thiopurines for inflammatory bowel disease are controversial. We assessed this risk in a prospective observational cohort study. METHODS 19,486 patients with inflammatory bowel disease, of whom 11,759 (60.3%) had Crohns disease and 7727 (39.7%) had ulcerative colitis or unclassified inflammatory bowel disease, were enrolled in a nationwide French cohort by 680 gastroenterologists, who reported details of immunosuppressive therapy during the observation period, cases of cancer, and deaths. The risk of lymphoproliferative disorder was assessed according to thiopurine exposure. Median follow-up was 35 months (IQR 29-40). FINDINGS At baseline, 5867 (30.1%) of patients were receiving, 2809 (14.4%) had discontinued, and 10,810 (55.5%) had never received thiopurines. 23 new cases of lymphoproliferative disorder were diagnosed, consisting of one case of Hodgkins lymphoma and 22 cases of non-Hodgkin lymphoproliferative disorder. The incidence rates of lymphoproliferative disorder were 0.90 per 1000 (95% CI 0.50-1.49) patient-years in those receiving, 0.20/1000 (0.02-0.72) patient-years in those who had discontinued, and 0.26/1000 (0.10-0.57) patient-years in those who had never received thiopurines (p=0.0054). The multivariate-adjusted hazard ratio of lymphoproliferative disorder between patients receiving thiopurines and those who had never received the drugs was 5.28 (2.01-13.9, p=0.0007). Most cases associated with thiopurine exposure matched the pathological range of post-transplant disease. INTERPRETATION Patients receiving thiopurines for inflammatory bowel disease have an increased risk of developing lymphoproliferative disorders. FUNDING Programme Hospitalier de Recherche Clinique National (AOM05157), Association François Aupetit, Délégation Inter-régionale de la Recherche clinique Ile de France-Assistance Publique Hôpitaux de Paris (AP-HP), Ligue contre le Cancer, and Fonds de Recherche de la Société Nationale Française de Gastro-entérologie.


Gut | 2006

European evidence based consensus on the diagnosis and management of Crohn's disease: current management.

Spl Travis; Eduard F. Stange; Marc Lemann; T. Öresland; Yehuda Chowers; Alastair Forbes; Geert R. D'Haens; G Kitis; A Cortot; Cosimo Prantera; P. Marteau; Colombel Jf; Paolo Gionchetti; Yoram Bouhnik; Emmanuel Tiret; J Kroesen; M Starlinger; Nj Mortensen

This second section of the European Crohn’s and Colitis Organisation (ECCO) Consensus on the management of Crohn’s disease concerns treatment of active disease, maintenance of medically induced remission, and surgery. The first section on definitions and diagnosis includes the aims and methods of the consensus, as well as sections on diagnosis, pathology, and classification of Crohn’s disease. The third section on special situations in Crohn’s disease includes postoperative recurrence, fistulating disease, paediatrics, pregnancy, psychosomatics, extraintestinal manifestations, and alternative therapy for Crohn’s disease.


Journal of Crohns & Colitis | 2008

European evidence-based Consensus on the management of ulcerative colitis: Current management

Simon Travis; Eduard F. Stange; Marc Lemann; T. Öresland; Willem A. Bemelman; Yehuda Chowers; Colombel Jf; Geert R. D'Haens; Subrata Ghosh; P. Marteau; Wolfgang Kruis; N.J.McC. Mortensen; Miquel Gassull

### 5.1 General The general principles for treating active ulcerative colitis are to consider the activity, distribution (proctitis, left-sided, extensive,1 and pattern of disease (relapse frequency, course of disease, response to previous medications, side-effect profile of medication, extra-intestinal manifestation), before treatment decisions are made in conjunction with the patient. #### 5.1.1 Disease activity The principal scoring systems used for clinical trials are covered in Section 5.1.2 and have been comprehensively reviewed.2 Some additional points are clinically relevant. In clinical practice it matters most to distinguish severe ulcerative colitis necessitating hospital admission from those with mild or moderate disease who can generally be treated as outpatients. The simplest, best validated and most widely used index for identifying acute severe UC remains that of Truelove & Wi_tts 3: any patient who has a bloody stool frequency ≥ 6/day and a tachycardia (> 90 bpm), or temperature > 37.8 °C, or anaemia (haemoglobin 30 mm/h) has severe ulcerative colitis (Table 1.3). This index has been used in 20/32 studies of intensive intravenous treatment for severe UC.4 Only one additional criterion in addition to the bloody stool frequency ≥ 6/day is needed to define a severe attack.5 While these criteria have the major limitation of being unresponsive and cannot track the course of disease, they do distinguish the severe from the moderate or mild and have value in everyday practice because they are easy to use, which no other index achieves. It should be standard practice to confirm active colitis by sigmoidoscopy or proctoscopy before starting treatment. Rectal mucosal biopsy helps exclude unexpected causes of symptoms similar to active disease (such as cytomegalovirus, amoebic, or other infection, rectal mucosal prolapse, Crohns disease, or even irritable bowel syndrome and haemorrhoidal bleeding). #### 5.1.2 Approach Patients should be encouraged to participate actively in …


Gastroenterology | 2012

Maintenance of remission among patients with Crohn's disease on antimetabolite therapy after infliximab therapy is stopped.

Edouard Louis; Jean Yves Mary; Gwenola Vernier–Massouille; Jean–Charles Grimaud; Yoram Bouhnik; David Laharie; Jean Louis Dupas; Hélène Pillant; Laurence Picon; Michel Veyrac; Mathurin Flamant; Guillaume Savoye; Raymond Jian; Martine Devos; Raphaël Porcher; Gilles Paintaud; Eric Piver; Jean-Frédéric Colombel; Marc Lemann

BACKGROUND & AIMS It is important to determine whether infliximab therapy can be safely interrupted in patients with Crohns disease who have undergone a period of prolonged remission. We assessed the risk of relapse after infliximab therapy was discontinued in patients on combined maintenance therapy with antimetabolites and identified factors associated with relapse. METHODS We performed a prospective study of 115 patients with Crohns disease who were treated for at least 1 year with scheduled infliximab and an antimetabolite and had been in corticosteroid-free remission for at least 6 months. Infliximab was stopped, and patients were followed up for at least 1 year. We associated demographic, clinical, and biologic factors with time to relapse using a Cox model. RESULTS After a median follow-up period of 28 months, 52 of the 115 patients experienced a relapse; the 1-year relapse rate was 43.9% ± 5.0%. Based on multivariable analysis, risk factors for relapse included male sex, the absence of surgical resection, leukocyte counts >6.0 × 10(9)/L, and levels of hemoglobin ≤145 g/L, C-reactive protein ≥5.0 mg/L, and fecal calprotectin ≥300 μg/g. Patients with no more than 2 of these risk factors (approximately 29% of the study population) had a 15% risk of relapse within 1 year. Re-treatment with infliximab was effective and well tolerated in 88% of patients who experienced a relapse. CONCLUSIONS Approximately 50% of patients with Crohns disease who were treated for at least 1 year with infliximab and an antimetabolite agent experienced a relapse within 1 year after discontinuation of infliximab. However, patients with a low risk of relapse can be identified using a combination of clinical and biologic markers.


Inflammatory Bowel Diseases | 2011

Development of the Crohn's disease digestive damage score, the Lemann score.

Benjamin Pariente; Jacques Cosnes; Silvio Danese; William J. Sandborn; Maãté Lewin; Joel G. Fletcher; Yehuda Chowers; Geert R. D'Haens; Brian G. Feagan; Toshifumi Hibi; Daniel W. Hommes; E. Jan Irvine; Michael A. Kamm; Edward V. Loftus; Edouard Louis; Pierre Michetti; Pia Munkholm; T. Öresland; Julián Panés; Laurent Peyrin-Biroulet; Walter Reinisch; Bruce E. Sands; Juergen Schoelmerich; Stefan Schreiber; Herbert Tilg; Simon Travis; Gert Van Assche; Maurizio Vecchi; Jean Yves Mary; Jean-Frederic Colombel

Crohns disease (CD) is a chronic progressive destructive disease. Currently available instruments measure disease activity at a specific point in time. An instrument to measure cumulative structural damage to the bowel, which may predict long-term disability, is needed. The aim of this article is to outline the methods to develop an instrument that can measure cumulative bowel damage. The project is being conducted by the International Program to develop New Indexes in Crohns disease (IPNIC) group. This instrument, called the Crohns Disease Digestive Damage Score (the Lémann score), should take into account damage location, severity, extent, progression, and reversibility, as measured by diagnostic imaging modalities and the history of surgical resection. It should not be “diagnostic modality driven”: for each lesion and location, a modality appropriate for the anatomic site (for example: computed tomography or magnetic resonance imaging enterography, and colonoscopy) will be used. A total of 24 centers from 15 countries will be involved in a cross-sectional study, which will include up to 240 patients with stratification according to disease location and duration. At least 120 additional patients will be included in the study to validate the score. The Lémann score is expected to be able to portray a patients disease course on a double-axis graph, with time as the x-axis, bowel damage severity as the y-axis, and the slope of the line connecting data points as a measure of disease progression. This instrument could be used to assess the effect of various medical therapies on the progression of bowel damage. (Inflamm Bowel Dis 2011)


The American Journal of Gastroenterology | 2011

The London Position Statement of the World Congress of Gastroenterology on Biological Therapy for IBD With the European Crohn's and Colitis Organization: When to Start, When to Stop, Which Drug to Choose, and How to Predict Response?

Geert R. D'Haens; Remo Panaccione; Peter D. Higgins; Severine Vermeire; Miquel Gassull; Yehuda Chowers; Stephen B. Hanauer; Hans H. Herfarth; Daan W. Hommes; Michael A. Kamm; Robert Löfberg; A. Quary; Bruce E. Sands; Ajit Sood; G. Watermayer; Bret A. Lashner; Marc Lemann; Scott E. Plevy; Walter Reinisch; Stefan Schreiber; Corey A. Siegel; S Targan; Mamoru Watanabe; Brian G. Feagan; William J. Sandborn; Jean-Frédéric Colombel; Simon Travis

The advent of biological therapy has revolutionized inflammatory bowel disease (IBD) care. Nonetheless, not all patients require biological therapy. Selection of patients depends on clinical characteristics, previous response to other medical therapy, and comorbid conditions. Availability, reimbursement guidelines, and patient preferences guide the choice of first-line biological therapy for luminal Crohns disease (CD). Infliximab (IFX) has the most extensive clinical trial data, but other biological agents (adalimumab (ADA), certolizumab pegol (CZP), and natalizumab (NAT)) appear to have similar benefits in CD. Steroid-refractory, steroid-dependent, or complex fistulizing CD are indications for starting biological therapy, after surgical drainage of any sepsis. For fistulizing CD, the efficacy of IFX for inducing fistula closure is best documented. Unique risks of NAT account for its labeling as a second-line biological agent in some countries. Patients who respond to induction therapy benefit from systematic re-treatment. The combination of IFX with azathioprine is better than monotherapy for induction of remission and mucosal healing up to 1 year in patients who are naïve to both agents. Whether this applies to other agents remains unknown. IFX is also effective for treatment-refractory, moderate, or severely active ulcerative colitis. Patients who have a diminished or loss of response to anti-tumor necrosis factor (TNF) therapy may respond to dose adjustment of the same agent or switching to another agent. Careful consideration should be given to the reasons for loss of response. There are insufficient data to make recommendations on when to stop anti-TNF therapy. Preliminary evidence suggests that a substantial proportion of patients in clinical remission for >1 year, without signs of active inflammation can remain in remission after stopping treatment.


Gut | 2006

Ineffectiveness of Lactobacillus johnsonii LA1 for prophylaxis of postoperative recurrence in Crohn's disease: a randomised, double blind, placebo controlled GETAID trial.

Philippe Marteau; Marc Lemann; Philippe Seksik; David Laharie; Jean F. Colombel; Yoram Bouhnik; Guillaume Cadiot; Jean-Claude Soulé; Arnaud Bourreille; Etienne Henry Metman; Eric Lerebours; Franck Carbonnel; Jean-Louis Dupas; Michel Veyrac; Benoit Coffin; Jacques Moreau; Vered Abitbol; S. Blum-Sperisen; Jean-Yves Mary

Background and aims: Early endoscopic recurrence is frequent after intestinal resection for Crohn’s disease. Bacteria are involved, and probiotics may modulate immune responses to the intestinal flora. Here we tested the probiotic strain Lactobacillus johnsonii LA1 in this setting. Patients and methods: This was a randomised, double blind, placebo controlled study. Patients were eligible if they had undergone surgical resection of <1 m, removing all macroscopic lesions within the past 21 days. Patients were randomised to receive two packets per day of lyophilised LA1 (2×109 cfu) or placebo for six months; no other treatment was allowed. The primary endpoint was endoscopic recurrence at six months, with grade >1 in Rutgeerts’ classification or an adapted classification for colonic lesions. Endoscopic score was the maximal grade of ileal and colonic lesions. Analyses were performed primarily on an intent to treat basis. Results: Ninety eight patients were enrolled (48 in the LA1 group). At six months, endoscopic recurrence was observed in 30/47 patients (64%) in the placebo group and in 21/43 (49%) in the LA1 group (p = 0.15). Per protocol analysis confirmed this result. Endoscopic score distribution did not differ significantly between the LA1 and placebo groups. There were four clinical recurrences in the LA1 group and three in the placebo group. Conclusion:L johnsonii LA1 (4×109 cfu/day) did not have a sufficient effect, if any, to prevent endoscopic recurrence of Crohn’s disease.


Gastroenterology | 2011

Increased risk for nonmelanoma skin cancers in patients who receive thiopurines for inflammatory bowel disease.

Laurent Peyrin Biroulet; Kiarash Khosrotehrani; Fabrice Carrat; Anne Marie Bouvier; Jean Baptiste Chevaux; Tabassome Simon; F. Carbonnel; Jean-Frédéric Colombel; Jean Louis Dupas; Philippe Godeberge; Jean Pierre Hugot; Marc Lemann; Stéphane Nahon; Jean–Marc Sabaté; Gilbert Tucat; Laurent Beaugerie

BACKGROUND & AIMS Patients with inflammatory bowel disease (IBD) who have been exposed to thiopurines might have an increased risk of skin cancer. We assessed this risk among patients in France. METHODS We performed a prospective observational cohort study of 19,486 patients with IBD, enrolled from May 2004 to June 2005, who were followed up until December 31, 2007. The incidence of nonmelanoma skin cancer (NMSC) in the general population, used for reference, was determined from the French Network of Cancer Registries. RESULTS Before the age of 50 years, the crude incidence rates of NMSC among patients currently receiving or who previously received thiopurines were 0.66/1000 and 0.38/1000 patient-years, respectively; these values were 2.59/1000 and 1.96/1000 patient-years for the age group of 50 to 65 years and 4.04/1000 and 5.70/1000 patient-years for patients older than 65 years. Among patients who had never received thiopurines, the incidence of NMSC was zero before the age of 50 years, 0.60/1000 for the ages of 50 to 65 years, and 0.84/1000 for those older than 65 years. A multivariate Cox regression model stratified by propensity score quintiles showed that ongoing thiopurine treatment (hazard ratio [HR], 5.9; 95% confidence interval [CI], 2.1-16.4; P = .0006) and past thiopurine exposure (HR, 3.9; 95% CI, 1.3-12.1; P = .02) were risk factors for NMSC. They also identified age per 1-year increase as a risk factor for NMSC (HR, 1.08; 95% CI, 1.05-1.11; P < .0001). CONCLUSIONS Ongoing and past exposure to thiopurines significantly increases the risk of NMSC in patients with IBD, even before the age of 50 years. These patients should be protected against UV radiation and receive lifelong dermatologic screening.

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Jean-Frederic Colombel

Icahn School of Medicine at Mount Sinai

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Olivier Dewit

Université catholique de Louvain

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