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Dive into the research topics where Valérie Pittet is active.

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Featured researches published by Valérie Pittet.


The American Journal of Gastroenterology | 2011

Frequency and risk factors for extraintestinal manifestations in the Swiss inflammatory bowel disease cohort.

Stephan R. Vavricka; Lionel Brun; Pierluigi Ballabeni; Valérie Pittet; Bettina M. Prinz Vavricka; Jonas Zeitz; Gerhard Rogler; Alain Schoepfer

OBJECTIVES:Data on the frequency of extraintestinal manifestations (EIMs) in Crohns disease (CD) and ulcerative colitis (UC) and analyses of their risk factors are scarce. We evaluated their prevalence and risk factors in a large nationwide cohort of inflammatory bowel disease (IBD) patients.METHODS:IBD patients from an adult clinical cohort in Switzerland (Swiss IBD cohort study) were prospectively included. Data from validated physician enrolment questionnaires were analyzed.RESULTS:A total of 950 patients were included, 580 (61%) with CD (mean age 41 years) and 370 (39%) with UC (mean age 42 years). Of these, 249 (43%) of CD and 113 (31%) of UC patients had one to five EIMs. The following EIMs were found: arthritis (CD 33%, UC 21%), aphthous stomatitis (CD 10%, UC 4%), uveitis (CD 6%, UC 4%), erythema nodosum (CD 6%, UC 3%), ankylosing spondylitis (CD 6%, UC 2%), psoriasis (CD 2%, UC 1%), pyoderma gangrenosum (CD and UC each 2%), and primary sclerosing cholangitis (CD 1%, UC 4%). Multiple logistic regression identified the following risk factors for ongoing EIM in CD: active disease (odds ratio (OR)=1.95, 95% confidence interval (CI)=1.17–3.23, P=0.01), and positive IBD family history (OR=1.77, 95% CI=1.07–2.92, P=0.025). No risk factors were identified in UC patients.CONCLUSIONS:EIMs are a frequent problem in CD and UC patients. Active disease and positive IBD family history are associated with ongoing EIM in CD patients. Identification of EIM prevalence and associated risk factors may result in increased awareness for this problem and thereby facilitating their diagnosis and therapeutic management.


Inflammatory Bowel Diseases | 2013

Fecal calprotectin more accurately reflects endoscopic activity of ulcerative colitis than the Lichtiger Index, C-reactive protein, platelets, hemoglobin, and blood leukocytes

Alain Schoepfer; Christoph Beglinger; Alex Straumann; Ekaterina Safroneeva; Yvonne Romero; David Armstrong; Carsten Schmidt; Michael Trummler; Valérie Pittet; Stephan R. Vavricka

Background:The correlation between noninvasive markers with endoscopic activity according to the modified Baron Index in patients with ulcerative colitis (UC) is unknown. We aimed to evaluate the correlation between endoscopic activity and fecal calprotectin (FC), C-reactive protein (CRP), hemoglobin, platelets, blood leukocytes, and the Lichtiger Index (clinical score). Methods:UC patients undergoing complete colonoscopy were prospectively enrolled and scored clinically and endoscopically. Samples from feces and blood were analyzed in UC patients and controls. Results:We enrolled 228 UC patients and 52 healthy controls. Endoscopic disease activity correlated best with FC (Spearmans rank correlation coefficient r = 0.821), followed by the Lichtiger Index (r = 0.682), CRP (r = 0.556), platelets (r = 0.488), blood leukocytes (r = 0.401), and hemoglobin (r = −0.388). FC was the only marker that could discriminate between different grades of endoscopic activity (grade 0, 16 [10–30] &mgr;g/g; grade 1, 35 [25–48] &mgr;g/g; grade 2, 102 [44–159] &mgr;g/g; grade 3, 235 [176–319] &mgr;g/g; grade 4, 611 [406–868] &mgr;g/g; P < 0.001 for discriminating the different grades). FC with a cutoff of 57 &mgr;g/g had a sensitivity of 91% and a specificity of 90% to detect endoscopically active disease (modified Baron Index ≥2). Conclusions:FC correlated better with endoscopic disease activity than clinical activity, CRP, platelets, hemoglobin, and blood leukocytes. The strong correlation with endoscopic disease activity suggests that FC represents a useful biomarker for noninvasive monitoring of disease activity in UC patients.


Inflammatory Bowel Diseases | 2012

Systematic evaluation of risk factors for diagnostic delay in inflammatory bowel disease

Stephan R. Vavricka; Sabrina Spigaglia; Gerhard Rogler; Valérie Pittet; Pierre Michetti; Christian Felley; Christian Mottet; Christian Braegger; Daniela Rogler; Alex Straumann; Peter Bauerfeind; Michael Fried; Alain Schoepfer

Background: The diagnosis of inflammatory bowel disease (IBD), comprising Crohns disease (CD) and ulcerative colitis (UC), continues to present difficulties due to unspecific symptoms and limited test accuracies. We aimed to determine the diagnostic delay (time from first symptoms to IBD diagnosis) and to identify associated risk factors. Methods: A total of 1591 IBD patients (932 CD, 625 UC, 34 indeterminate colitis) from the Swiss IBD cohort study (SIBDCS) were evaluated. The SIBDCS collects data on a large sample of IBD patients from hospitals and private practice across Switzerland through physician and patient questionnaires. The primary outcome measure was diagnostic delay. Results: Diagnostic delay in CD patients was significantly longer compared to UC patients (median 9 versus 4 months, P < 0.001). Seventy‐five percent of CD patients were diagnosed within 24 months compared to 12 months for UC and 6 months for IC patients. Multivariate logistic regression identified age <40 years at diagnosis (odds ratio [OR] 2.15, P = 0.010) and ileal disease (OR 1.69, P = 0.025) as independent risk factors for long diagnostic delay in CD (>24 months). In UC patients, nonsteroidal antiinflammatory drug (NSAID intake (OR 1.75, P = 0.093) and male gender (OR 0.59, P = 0.079) were associated with long diagnostic delay (>12 months). Conclusions: Whereas the median delay for diagnosing CD, UC, and IC seems to be acceptable, there exists a long delay in a considerable proportion of CD patients. More public awareness work needs to be done in order to reduce patient and doctor delays in this target population. (Inflamm Bowel Dis 2012;)


International Journal of Epidemiology | 2009

Cohort Profile: The Swiss Inflammatory Bowel Disease Cohort Study (SIBDCS)

Valérie Pittet; Pascal Juillerat; Christian Mottet; Christian Felley; Pierluigi Ballabeni; Bernard Burnand; Pierre Michetti; John-Paul Vader

Background Crohn’s disease, ulcerative colitis and indeterminate colitis are the three subtypes of disease collectively known as inflammatory bowel diseases: relapsing and remitting conditions characterized by chronic inflammation which is limited to the colon in ulcerative colitis, whereas it can involve various sites in the gastrointestinal tract in Crohn’s disease. The pathogenesis of inflammatory bowel disease is currently still unclear, although humoral and cell-mediated immune system, as well as environmental [hygiene, smoking, nonsteroidal anti-inflammatory drugs (NSAIDs) use, geographic location] and genetic factors are known to be involved in the occurrence of these diseases. Patients often require continuous medication as well as one or more intestinal resections. The care of these patients is evolving rapidly with the introduction of novel therapies and treatment plans. Some of these new treatments are expensive and their efficacy is usually limited to 30–50% of patients. In the absence of markers able to predict response to specific therapies, all eligible patients currently receive several of these drugs. They are thus exposed to side-effects which contribute to the high overall cost of these therapies—half the average medical costs associated with the disease,—while only a fraction of those treated will benefit at each stage. Impact on patient quality of life is often considerable, especially because disease onset can occur already in the first or second decade of life, while patients are either in full-time education or just entering the workforce. The negative impact on social life or ability to achieve, either scholastically or professionally, can severely affect professional as well as family life. Indeed, 450% of patients with Crohn’s disease indicate that their disease has an influence on their professional and personal life. The course of the disease is often characterized by progressive worsening of the patient’s condition, with increasing frequency of hospitalization and considerable indirect costs through absenteeism and disability allowances. Disease activity is known to be influenced by psychological factors.


Endoscopy | 2009

Appropriateness of colonoscopy in Europe (EPAGE II) Screening for colorectal cancer

C. Arditi; Isabelle Peytremann-Bridevaux; Bernard Burnand; V. F. Eckardt; P. Bytzer; L. Agréus; Robert W. Dubois; John-Paul Vader; Florian Froehlich; Valérie Pittet; S. Schusselé Filliettaz; Pascal Juillerat; Jean-Jacques Gonvers

BACKGROUND AND STUDY AIMS To summarize the published literature on assessment of appropriateness of colonoscopy for screening for colorectal cancer (CRC) in asymptomatic individuals without personal history of CRC or polyps, and report appropriateness criteria developed by an expert panel, the 2008 European Panel on the Appropriateness of Gastrointestinal Endoscopy, EPAGE II. METHODS A systematic search of guidelines, systematic reviews, and primary studies regarding colonoscopy for screening for colorectal cancer was performed. The RAND/UCLA Appropriateness Method was applied to develop appropriateness criteria for colonoscopy in these circumstances. RESULTS Available evidence for CRC screening comes from small case-controlled studies, with heterogeneous results, and from indirect evidence from randomized controlled trials (RCTs) on fecal occult blood test (FOBT) screening and studies on flexible sigmoidoscopy screening. Most guidelines recommend screening colonoscopy every 10 years starting at age 50 in average-risk individuals. In individuals with a higher risk of CRC due to family history, there is a consensus that it is appropriate to offer screening colonoscopy at < 50 years. EPAGE II considered screening colonoscopy appropriate above 50 years in average-risk individuals. Panelists deemed screening colonoscopy appropriate for younger patients, with shorter surveillance intervals, where family or personal risk of colorectal cancer is higher. A positive FOBT or the discovery of adenomas at sigmoidoscopy are considered appropriate indications. CONCLUSIONS Despite the lack of evidence based on randomized controlled trials (RCTs), colonoscopy is recommended by most published guidelines and EPAGE II criteria available online (http://www.epage.ch), as a screening option for CRC in individuals at average risk of CRC, and undisputedly as the main screening tool for CRC in individuals at moderate and high risk of CRC.


The American Journal of Gastroenterology | 2013

Diagnostic Delay in Crohn ' s Disease Is Associated With a Complicated Disease Course and Increased Operation Rate

Alain Schoepfer; Mohamed-Ali Dehlavi; Nicolas Fournier; Ekaterina Safroneeva; Alex Straumann; Valérie Pittet; Laurent Peyrin-Biroulet; Pierre Michetti; Gerhard Rogler; Stephan R. Vavricka

OBJECTIVES:The impact of diagnostic delay (a period from appearance of first symptoms to diagnosis) on the clinical course of Crohns disease (CD) is unknown. We examined whether length of diagnostic delay affects disease outcomes.METHODS:Data from the Swiss IBD cohort study were analyzed. Patients were recruited from university centers (68%), regional hospitals (14%), and private practices (18%). The frequencies of occurrence of bowel stenoses, internal fistulas, perianal fistulas, and CD-related surgery (intestinal and perianal) were analyzed.RESULTS:A total of 905 CD patients (53.4% female, median age at diagnosis 26 (20–36) years) were stratified into four groups according to the quartiles of diagnostic delay (0–3, 4–9, 10–24, and ≥25 months, respectively). Median diagnostic delay was 9 (3–24) months. The frequency of immunomodulator and/or antitumor necrosis factor drug use did not differ among the four groups. The length of diagnostic delay was positively correlated with the occurrence of bowel stenosis (odds ratio (OR) 1.76, P=0.011 for delay of ≥25 months) and intestinal surgery (OR 1.76, P=0.014 for delay of 10–24 months and OR 2.03, P=0.003 for delay of ≥25 months). Disease duration was positively associated and non-ileal disease location was negatively associated with bowel stenosis (OR 1.07, P<0.001, and OR 0.41, P=0.005, respectively) and intestinal surgery (OR 1.14, P<0.001, and OR 0.23, P<0.001, respectively).CONCLUSIONS:The length of diagnostic delay is correlated with an increased risk of bowel stenosis and CD-related intestinal surgery. Efforts should be undertaken to shorten the diagnostic delay.


Journal of Crohns & Colitis | 2010

Prevalence of anaemia in inflammatory bowel disease in Switzerland: A cross-sectional study in patients from private practices and university hospitals

Manuela Voegtlin; Stephan R. Vavricka; Alain Schoepfer; Alex Straumann; Juerg Voegtlin; Gerhard Rogler; Pierluigi Ballabeni; Valérie Pittet; Andreas Buser; Michael Fried; Christoph Beglinger

BACKGROUND Anaemia represents a common complication of inflammatory bowel disease (IBD). Most studies on anaemia in IBD patients have been performed in tertiary referral centres (RC) and data from gastroenterologic practices (GP) are lacking. We investigated the frequency and severity of anaemia in IBD patients from tertiary referral centres and gastroenterologic practices compared to the general population. METHODS Data were acquired from patients included in the Swiss IBD Cohort Study. IBD activity was evaluated by CDAI and modified Truelove and Witts severity index (MTWSI). Anaemia was defined as haemoglobin ≤120g/L in women and ≤130g/L in men. RESULTS 125 patients from RC (66 with Crohns disease (CD) and 59 with ulcerative colitis (UC)) and 116 patients from GP (71 CD and 45 UC) were included and compared to 6074 blood donors. Anaemia was found in 21.2% (51/241) of the IBD patients and more frequently in patients from RC as compared to GP and healthy controls (28.8% vs. 12.9% vs. 3.4%; P<0.01). IBD patients from RC suffered more frequently from active disease compared to IBD patients in GP (36% vs. 23%, P=0.032). Supplementation therapy (iron, vitamin B12, folic acid) was performed in 40% of anaemic IBD patients in GP as compared to 43% in RC. CONCLUSIONS Anaemia is a common complication in patients with IBD and significantly more prevalent in patients from referral centres as compared to patients from gastroenterologic practices. Physicians treating IBD patients should pay attention to the presence of anaemia and ensure sufficient supplementation therapy.


Inflammatory Bowel Diseases | 2012

Crohn's disease-associated polymorphism within the PTPN2 gene affects muramyl-dipeptide-induced cytokine secretion and autophagy.

Michael Scharl; Jessica Mwinyi; Anne Fischbeck; Katharina Leucht; Jyrki J. Eloranta; Joba M. Arikkat; Theresa Pesch; Silvia Kellermeier; Alma Mair; Gerd A. Kullak-Ublick; Kaspar Truninger; Faiza Noreen; Jaroslaw Regula; Pawel Gaj; Valérie Pittet; Christoph Mueller; Claudia Hofmann; Michael Fried; Declan F. McCole; Gerhard Rogler

Background: The single nucleotide polymorphism (SNP) rs2542151 within the gene locus region encoding protein tyrosine phosphatase non‐receptor type 2 (PTPN2) has been associated with Crohns disease (CD), ulcerative colitis (UC), type‐I diabetes, and rheumatoid arthritis. We have previously shown that PTPN2 regulates mitogen‐activated protein kinase (MAPK) signaling and cytokine secretion in human THP‐1 monocytes and intestinal epithelial cells (IEC). Here, we studied whether intronic PTPN2 SNP rs1893217 regulates immune responses to the nucleotide‐oligomerization domain 2 (NOD2) ligand, muramyl‐dipeptide (MDP). Materials and Methods: Genomic DNA samples from 343 CD and 663 non‐IBD control patients (male and female) from a combined German, Swiss, and Polish cohort were genotyped for the presence of the PTPN2 SNPs, rs2542151, and rs1893217. PTPN2‐variant rs1893217 was introduced into T84 IEC or THP‐1 cells using a lentiviral vector. Results: We identified a novel association between the genetic variant, rs1893217, located in intron 7 of the PTPN2 gene and CD. Human THP‐1 monocytes carrying this variant revealed increased MAPK activation as well as elevated mRNA expression of T‐bet transcription factor and secretion of interferon‐&ggr; in response to the bacterial wall component, MDP. In contrast, secretion of interleukin‐8 and tumor necrosis factor were reduced. In both, T84 IEC and THP‐1 monocytes, autophagosome formation was impaired. Conclusions: We identified a novel CD‐associated PTPN2 variant that modulates innate immune responses to bacterial antigens. These findings not only provide key insights into the effects of a functional mutation on a clinically relevant gene, but also reveal how such a mutation could contribute to the onset of disease. (Inflamm Bowel Dis 2011;)


Endoscopy | 2009

Appropriateness of colonoscopy in Europe (EPAGE II) – Surveillance after polypectomy and after resection of colorectal cancer

C. Arditi; Jean-Jacques Gonvers; Bernard Burnand; G. Minoli; D. Oertli; F. Lacaine; Robert W. Dubois; John-Paul Vader; S. Schusselé Filliettaz; Isabelle Peytremann-Bridevaux; Valérie Pittet; Pascal Juillerat; Florian Froehlich

BACKGROUND AND STUDY AIMS To summarize the published literature on assessment of appropriateness of colonoscopy for surveillance after polypectomy and after curative-intent resection of colorectal cancer (CRC), and report appropriateness criteria developed by an expert panel, the 2008 European Panel on the Appropriateness of Gastrointestinal Endoscopy, EPAGE II. METHODS A systematic search of guidelines, systematic reviews and primary studies regarding the evaluation and management of surveillance colonoscopy after polypectomy and after resection of CRC was performed. The RAND/UCLA Appropriateness Method was applied to develop appropriateness criteria for colonoscopy for these conditions. RESULTS Most CRCs arise from adenomatous polyps. The characteristics of removed polyps, especially the distinction between low-risk adenomas (1 or 2, small [< 1 cm], tubular, no high-grade dysplasia) vs. high-risk adenomas (large [> or = 1 cm], multiple [> 3], high-grade dysplasia or villous features), have an impact on advanced adenoma recurrence. Most guidelines recommend a 3-year follow-up colonoscopy for high-risk adenomas and a 5-year colonoscopy for low-risk adenomas. Despite the lack of evidence to support or refute any survival benefit for follow-up colonoscopy after curative-intent CRC resection, surveillance colonoscopy is recommended by most guidelines. The timing of the first surveillance colonoscopy differs. The expert panel considered that 56 % of the clinical indications for colonoscopy for surveillance after polypectomy were appropriate. For surveillance after CRC resection, it considered colonoscopy appropriate 1 year after resection. CONCLUSIONS Colonoscopy is recommended as a first-choice procedure for surveillance after polypectomy by all published guidelines and by the EPAGE II criteria. Despite the limitations of the published studies, colonoscopy is also recommended by most of the guidelines and by EPAGE II criteria for surveillance after curative-intent CRC resection.


Endoscopy | 2009

Appropriateness of colonoscopy in Europe (EPAGE II). Presentation of methodology, general results, and analysis of complications.

Pascal Juillerat; Isabelle Peytremann-Bridevaux; John-Paul Vader; C. Arditi; S. Schusselé Filliettaz; Robert W. Dubois; Jean-Jacques Gonvers; Florian Froehlich; Bernard Burnand; Valérie Pittet

BACKGROUND AND STUDY AIMS Appropriate use of colonoscopy is a key component of quality management in gastrointestinal endoscopy. In an update of a 1998 publication, the 2008 European Panel on the Appropriateness of Gastrointestinal Endoscopy (EPAGE II) defined appropriateness criteria for various colonoscopy indications. This introductory paper therefore deals with methodology, general appropriateness, and a review of colonoscopy complications. METHODS The RAND/UCLA Appropriateness Method was used to evaluate the appropriateness of various diagnostic colonoscopy indications, with 14 multidisciplinary experts using a scale from 1 (extremely inappropriate) to 9 (extremely appropriate). Evidence reported in a comprehensive updated literature review was used for these decisions. Consolidation of the ratings into three appropriateness categories (appropriate, uncertain, inappropriate) was based on the median and the heterogeneity of the votes. The experts then met to discuss areas of disagreement in the light of existing evidence, followed by a second rating round, with a subsequent third voting round on necessity criteria, using much more stringent criteria (i. e. colonoscopy is deemed mandatory). RESULTS Overall, 463 indications were rated, with 55 %, 16 % and 29 % of them being judged appropriate, uncertain and inappropriate, respectively. Perforation and hemorrhage rates, as reported in 39 studies, were in general < 0.1 % and < 0.3 %, respectively CONCLUSIONS The updated EPAGE II criteria constitute an aid to clinical decision-making but should in no way replace individual judgment. Detailed panel results are freely available on the internet (www.epage.ch) and will thus constitute a reference source of information for clinicians.

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