Alex Straumann

Viollier AG, Bâle, Basel-City, Switzerland

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Publications (100)705.14 Total impact

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    ABSTRACT: Long-lasting food impactions requiring endoscopic bolus removal occur frequently in patients with eosinophilic esophagitis (EoE) and harbour a risk for severe esophageal injuries. We evaluated whether treatment with swallowed topical corticosteroids is able to reduce the risk of occurrence of this complication.
    Allergy 06/2014; · 5.88 Impact Factor
  • Alex Straumann
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    ABSTRACT: Twenty years have passed since eosinophilic esophagitis was first recognized as a new and distinct entity. Current treatment modalities for eosinophilic esophagitis include the "3 Ds": drugs, allergen avoidance with diet, and esophageal dilation. Drugs entail the limitation that only corticosteroids have a proven efficacy; most other compounds evoke only a minimal effect. Diets must be maintained continuously and they interfere markedly with the quality of life, possibly even involving some risk of malnutrition. A greater understanding of the immunopathogenesis, natural history, and disease spectrum will inevitably lead to improved therapeutic outcomes for this emerging entity.
    Gastroenterology clinics of North America 06/2014; 43(2):385-394. · 2.56 Impact Factor
  • Alex Straumann, Alain Schoepfer
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    ABSTRACT: The identification of a distinct syndrome, designated eosinophilic oesophagitis (EoE), with its own clinical and histopathological characteristics, was first described in the early 1990s. Meanwhile intense research has uncovered many molecular, immunological and clinical aspects of this chronic-inflammatory disorder. This article focuses exclusively on basic and clinical insights of EoE gathered during the last few years. Regarding aetiopathogenesis it has become clear that EoE is a food-triggered disease with milk and wheat as the dominant culprit food categories. However, it is still debated whether a disturbed mucosal integrity allowing allergens to cross the mucosal barrier, or changes in wheat and milk manufacturing might induce these inflammatory responses. Furthermore, basic science and clinical studies have accordingly confirmed that a chronic eosinophilic inflammation leads to a remodelling of the oesophagus with micro- and macro-morphological alterations, ending in a strictured oesophagus with impaired function. Fortunately, long-term therapeutic trials, using either topical corticosteroids or dietary allergen avoidance, have demonstrated that this sequela can be prevented or even reversed. This finding is of clinical relevance as it supports the initiation of a consistent anti-inflammatory therapy. Nevertheless, EoE is still an enigmatic disease and the long list of unanswered questions will certainly stimulate further research.
    Gut 04/2014; · 10.73 Impact Factor
  • Article: Reply.
    Alain Schoepfer, Alex Straumann
    Gastroenterology 03/2014; · 12.82 Impact Factor
  • Hans-Uwe Simon, Alex Straumann
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    ABSTRACT: Background: Eosinophilic esophagitis (EoE) is a chronic inflammatory disease of the esophagus associated with dysphagia in adults and refractory reflux syndromes in children. Methods: Immunological and genetic approaches have been used to better understand the pathophysiology of the underlying inflammation. Results and Conclusions: Evidence has accumulated that EoE represents a T-helper (Th) 2-type inflammatory disease, in which allergens play a role in triggering the disease. The majority of the patients suffer from concurrent allergic rhinitis, asthma, and eczema, and have a history of atopy. The chronic inflammatory response in EoE is associated with tissue damage and remodeling, both of which lead to esophageal dysfunction and bolus impaction. The new insights into the pathophysiology have resulted in the development of the first pharmacological therapies of EoE. © 2014 S. Karger AG, Basel.
    Digestive Diseases 01/2014; 32(1-2):11-4. · 2.73 Impact Factor
  • Dagmar Simon, Alex Straumann, Hans-Uwe Simon
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    ABSTRACT: Eosinophilic esophagitis (EoE) has been associated with allergic diseases of the airways and skin. Here, we review the current literature on the sensitization pattern of adult EoE patients and critically discuss the diagnostic and therapeutic tools available. Most EoE patients have elevated total IgE levels in serum and are sensitized to aero- and food allergens as assessed by measuring specific IgE levels and/or the skin prick test. Whereas in children with EoE sensitization to food allergens predominate, in adults EoE symptoms do not correlate with IgE sensitization to specific food allergens. However, in two thirds of adult EoE patients, sensitization to cross-reactive plant allergen components have been be detected, mainly to profilins and PR10 proteins. So far, food triggering EoE can only be identified by an elimination diet and following reintroduction controlled by endoscopy and histology. Further research is required to elucidate the role of allergens in the pathogenesis of EoE and develop appropriate tools for diagnostic and specific treatment. © 2014 S. Karger AG, Basel.
    Digestive Diseases 01/2014; 32(1-2):30-3. · 2.73 Impact Factor
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    ABSTRACT: OBJECTIVES:The impact of diagnostic delay (a period from appearance of first symptoms to diagnosis) on the clinical course of Crohn's 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.Am J Gastroenterol advance online publication, 27 August 2013; doi:10.1038/ajg.2013.248.
    The American Journal of Gastroenterology 08/2013; · 7.55 Impact Factor
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    ABSTRACT: Development of strictures is a major concern for patients with eosinophilic esophagitis (EoE). At diagnosis, EoE can present with an inflammatory phenotype (characterized by whitish exudates, furrows, and edema), a stricturing phenotype (characterized by rings and stenosis), or a combination of these. Little is known about progression of stricture formation; we evaluated stricture development over time in the absence of treatment and investigated risk factors for stricture formation. We performed a retrospective study using the Swiss EoE Database, collecting data on 200 patients with symptomatic EoE (153 men; mean age at diagnosis, 39±15 y old). Stricture severity was graded based on the degree of difficulty associated with passing of the standard adult endoscope. The median delay in diagnosis of EoE was 6 y (inter-quartile range, 2-12 y). With increasing duration of delay in diagnosis, the prevalence of fibrotic features of EoE, based on endoscopy, increased from 46.5% (diagnostic delay, 0-2 years) to 87.5% (diagnostic delay, >20 y; P=.020). Similarly, the prevalence of esophageal strictures increased with duration of diagnostic delay, from 17.2% (diagnostic delay, 0-2 years) to 70.8% (diagnostic delay, >20 y; P<.001). Diagnostic delay was the only risk factor for strictures at the time of EoE diagnosis (odds ratio, 1.08; 95% confidence interval, 1.040-1.122; P<.001). The prevalence of esophageal strictures correlates with the duration of untreated disease. These findings indicate the need to minimize delay in diagnosis of EoE.
    Gastroenterology 08/2013; · 12.82 Impact Factor
  • D Simon, A Straumann, C Dahinden, H-U Simon
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    ABSTRACT: BACKGROUND: Eosinophilic esophagitis (EoE) is often associated with atopic airway and skin diseases. More than 80% of EoE patients are sensitized to aero- and/or food allergens. Immunoglobulin (Ig)E-mediated immune responses to microbes have been reported to be deleterious in connection with atopic diseases. AIM: The aim of this study was to obtain a comprehensive overview about the sensitization spectrum of adult EoE patients. METHODS: IgE in sera of 35 patients with active EoE were analyzed for reactivity to Candida albicans, as well as to a panel of recombinant and purified natural allergen components, using a microarray. RESULTS: IgE sensitization to Candida albicans was found in 43% of EoE patients. More than 80% of EoE patients were sensitized to aeroallergens and 22% to food-specific allergen components, whereas 69% of the patients exhibited specific IgE to cross-reactive allergens. Among the latter, profilins were identified as most frequent IgE cross-reactive allergen components. Interestingly, dysphagia, the main symptom of adult EoE patients following rice and/or bread ingestion, was associated with sensitization to cross-reactive allergens such as profilins, pathogenesis-related (PR) 10 and lipid transfer proteins (LTP). Intolerance toward meat rarely correlated with sensitization to animal food allergens. CONCLUSION: Candida albicans and cross-reactive plant allergen components, in particular profilins, were identified as frequent sensitizers in adult EoE patients. Specific elimination therapies are suggested to reveal their actual roles in the pathogenesis of EoE.
    Allergy 06/2013; · 5.88 Impact Factor
  • C Bussmann, A Straumann
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    ABSTRACT: Eosinophilic esophagitis is a chronic, clinically and histologically defined, inflammatory condition of the esophagus. The histological hallmark of eosinophilic esophagitis is a relevant, often patchy infiltration of the esophageal mucosa with eosinophils. In a consensus report a threshold value of approximately 120 eosinophils per mm2 was arbitrarily fixed as a diagnostic criterion. Noteworthy for the quantification of the eosinophilic infiltration are several technical facts, for instance size and covering extent of the biopsy specimen of the high-power field (hpf) and quality of embedding of biopsy specimens have to be considered. In order to establish the histological diagnosis several additional abnormalities must be included in the assessment and gastrointestinal reflux disease is the main differential diagnosis of eosinophilic esophagitis. Finally it is emphasized that for an affirmative diagnosis of eosinophilic esophagitis, in addition to the histological findings the clinical facts must be included.
    Der Pathologe 03/2013; 34(2):110-117. · 0.62 Impact Factor
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    ABSTRACT: BACKGROUND: Eosinophilic esophagitis (EoE) is a chronic, Th2-type inflammatory disease. Chemoattractant receptor-homologous molecule on Th2 cells (CRTH2) is a prostaglandin D(2) (PGD(2) ) receptor, expressed by Th2 cells and other inflammatory cells, including eosinophils and basophils, that mediates chemotaxis and activation. OC000459 is a selective CRTH2 antagonist and would be expected to suppress eosinophilic tissue inflammation. The purpose of this study was to evaluate the efficacy and safety of an OC000459 monotherapy in adult patients with active, corticosteroid-dependent or corticosteroid-refractory EoE. METHODS: In this randomized, double-blind, placebo-controlled trial, 26 adult patients (m/f = 22/4; mean age 41 years, range 22-69 years) with active EoE, dependent or resistant to corticosteroids, were treated either with 100 mg OC000459 (n = 14) or placebo (n = 12) twice daily. Pre- and post-treatment disease activity was assessed clinically, endoscopically, histologically, and via biomarkers. The primary end point was the reduction in esophageal eosinophil infiltration. RESULTS: After an 8-week OC000459 treatment, the esophageal eosinophil load decreased significantly, from 114.83 to 73.26 eosinophils per high-power field [(eos/hpf), P = 0.0256], whereas no reduction was observed with placebo (102.80-99.47 eos/hpf, P = 0.870). With OC000459, the physician's global assessment of disease activity improved from 7.13 to 5.18 (P = 0.035). OC000459 likewise reduced extracellular deposits of eosinophil peroxidase and tenascin C, the effects not seen with placebo. No serious adverse events were observed. CONCLUSIONS: An 8-week treatment with the CRTH2-antagonist, OC000459, exerts modest, but significant, anti-eosinophil and beneficial clinical effects in adult patients with active, corticosteroid-dependent or corticosteroid-refractory EoE and is well tolerated.
    Allergy 02/2013; · 5.88 Impact Factor
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    ABSTRACT: Background/Aims: Topically administered glucocorticoids such as budesonide have the potential of being established as first-line medical treatment of eosinophilic esophagitis (EoE). Safety of budesonide is based on high elimination by cytochrome P450 3A (CYP3A) enzymes. We aimed to investigate systemic absorption and elimination of a new budesonide formulation in patients with active EoE in comparison with healthy controls. Methods: After single and multiple doses of orodispersible budesonide (4 mg/day) the parent drug, its CYP3A-dependent metabolites, and endogenous cortisol were determined in 12 adult patients with active EoE and 12 healthy controls. An approved ileal-release formulation of budesonide was taken for reference. Molar ratios of metabolite formation in plasma were used as indices of CYP3A metabolic function. Results: CYP3A-dependent metabolite formation was significantly reduced in patients with active EoE as compared to healthy controls. Impaired biotransformation was reflected by a significantly higher extent of budesonide absorption and elongated elimination half-life in EoE patients. Comparison of morning serum cortisol levels at baseline with those after 1 week of treatment with budesonide revealed a significant decrease in EoE patients but not in healthy subjects. Conclusion: Active EoE is associated with reduced elimination of budesonide via CYP3A, the major subfamily of drug-metabolizing enzymes in humans.
    Digestion 01/2013; 87(2):110-117. · 1.94 Impact Factor
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    ABSTRACT: 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 (Spearman's 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] μg/g; grade 1, 35 [25-48] μg/g; grade 2, 102 [44-159] μg/g; grade 3, 235 [176-319] μg/g; grade 4, 611 [406-868] μg/g; P < 0.001 for discriminating the different grades). FC with a cutoff of 57 μg/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 01/2013; · 5.12 Impact Factor
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    ABSTRACT: Sublingual immunotherapy (SLIT) is increasingly investigated and utilized for the treatment of food and pollen allergies. Previous case reports suggested that eosinophilic esophagitis (EoE) might develop as a long-term complication in children after completion of oral immunotherapy. Here, we describe a 44-year-old female with a medical history of pollinosis who for the first time in her life developed complete manifestation of EoE (peak eosinophils 164/high power field) 4 weeks after initiation of SLIT using specific soluble allergens (hazelnut, birch, alder) according to previous specific serum IgE testing. After discontinuation of SLIT, EoE resolved completely within 4 weeks without any other medical intervention. During a follow-up of 12 months the patient remained free of any esophageal symptoms. This is the first case report demonstrating a close and therefore likely causative association between pollen SLIT and EoE in an adult patient.
    Case Reports in Gastroenterology 01/2013; 7(3):363-8.
  • Oral Alpan, Stephan Miehlke, Alex Straumann
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    ABSTRACT: To the Editor: In the study by Burks et al. (July 19 issue),(1) 22 of 40 patients (55%) passed the oral food challenge of 5 g of egg-white powder after 10 months of oral immunotherapy with egg-white powder. However, in the study by Burks et al., no oral food challenge was performed at baseline, although children with a history of anaphylaxis after egg ingestion were excluded. No clinical history of allergic symptoms and no in vitro test reliably predicts clinical food allergy.(2),(3) How can we be sure that the children had egg allergy at baseline and the results of . . .
    New England Journal of Medicine 10/2012; 367(15):1472; author reply 1472-3. · 54.42 Impact Factor
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    Dataset: 2012-TREAD

Publication Stats

3k Citations
705.14 Total Impact Points

Institutions

  • 2013
    • Viollier AG
      Bâle, Basel-City, Switzerland
    • Dr. Falk Pharma GmbH
      Freiburg, Baden-Württemberg, Germany
  • 2009–2013
    • Universitätsspital Basel
      Bâle, Basel-City, Switzerland
    • McMaster University
      • Farncombe Family Digestive Health Research Institute
      Hamilton, Ontario, Canada
  • 2006–2013
    • University Hospital of Lausanne
      • Service de gastro-entérologie et d'hépatologie
      Lausanne, Vaud, Switzerland
    • Boston Children's Hospital
      • Division of Gastroenterology, Hepatology and Nutrition
      Boston, MA, United States
  • 2012
    • Cincinnati Children's Hospital Medical Center
      • Department of Pediatrics
      Cincinnati, OH, United States
    • Universität Basel
      Bâle, Basel-City, Switzerland
  • 2011
    • University of Lausanne
      Lausanne, Vaud, Switzerland
  • 2007–2011
    • Universität Bern
      • Institut für Pharmakologie
      Bern, BE, Switzerland
  • 2008
    • Inselspital, Universitätsspital Bern
      Berna, Bern, Switzerland