Evaluation of oesophageal mucosa integrity by the intraluminal impedance technique
- Ricard Farré1,2,
- Kathleen Blondeau1,
- Dominique Clement1,
- Maria Vicario2,3,
- Lucia Cardozo1,
- Michael Vieth4,
- Veerle Mertens1,
- Ans Pauwels1,
- Jiri Silny5,
- Marcel Jimenez2,6,
- Jan Tack1,
- Daniel Sifrim1,7
- 1Translational Research Center for Gastrointestinal Disorders, Catholic University Leuven, Leuven, Belgium
- 2Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas, (Ciberehd), Instituto de Salud Carlos III, Spain
- 3Digestive Diseases Research Unit, Institut de Recerca, Department of Gastroenterology, Hospital Universitari Vall d'Hebron, Universitat Autònoma de Barcelona, Barcelona, Spain
- 4Department of Pathology, Institute of Pathology, Bayreuth Hospital, Bayreuth, Germany
- 5The Research Center for Bioelectromagnetic Interaction (femu), University Hospital of Aachen, Aachen, Germany
- 6Department of Cell Biology, Physiology and Immunology, Universitat Autònoma de Barcelona, Barcelona, Spain
- 7Barts and The London School of Medicine and Dentistry, Queen Mary University of London, UK
- Correspondence to Dr Ricard Farré, Translational Research Center for Gastrointestinal Disorders, Gasthuisberg, O& N 1, 7th floor, Herestraat 49 -bus 701, Leuven 3000, Belgium;
- Revised 7 December 2010
- Accepted 24 December 2010
- Published Online First 8 February 2011
Background Oesophageal intraluminal impedance is currently used for assessment of reflux in gastro-oesophageal reflux disease (GORD). Oesophageal mucosa integrity may have a key role in heartburn perception in non-erosive reflux disease (NERD). Severe erosive oesophagitis is associated with low impedance baseline. We hypothesised that impedance baseline measurements could be used to evaluate changes in oesophageal mucosa integrity in man.
Methods We measured oesophageal impedance baseline before, during and after acid perfusion in rabbits and healthy subjects. Transepithelial resistance (TER) was determined and dilated intercellular spaces (DIS) were assessed in isolated rabbit oesophageal mucosa. Impedance baseline was measured retrospectively at different levels of the oesophagus in impedance-pH recordings from asymptomatic volunteers and patients with GORD.
Results In healthy subjects and rabbits, impedance baseline dropped dramatically during perfusion of control solution (pH 7.2) but after perfusion, impedance recovered. In rabbits, after perfusion with saline pH 1.5 and 1.0 impedance values remained a 39.1±7.0% and 63.9±6.5% (p<0.05) lower respectively. There was a positive correlation between in vivo basal impedance and in vitro TER values (r=0.72, p=0.0021). Tissue showed no erosions but both acidic solutions induced DIS. In healthy subjects, after perfusion with saline pH 2.0 and 1.0 the impedance baseline remained lower a 21.9±6.5% and 52.7±5.0%, (p<0.0001) respectively. Patients with GORD have a lower impedance baseline than healthy volunteers at the distal oesophagus.
Conclusions Impedance baseline measurements might be used to evaluate the status of the oesophageal mucosa and to study the role of the impaired mucosal integrity in acid-induced heartburn in healthy volunteers and in patients with GORD.
- Impedance baseline
- impaired integrity
- gastro-oesophageal reflux disease
- non-erosive reflux disease
- healthy volunteers
- epithelial barrier
- gastro-oesophageal reflux disease
- oesophageal reflux
RF and KB contributed equally to this paper.
Funding This work was supported by a ‘‘Geconcerteerde Onderzoeksactie’’ grant from the Catholic University of Leuven, Belgium and by Ministerio de Ciencia e Innovación (BFU2009-11118). RF and KB are postdoctoral fellows supported by FWO (Research Foundation, Flanders).
Competing interests None.
Ethics approval The procedure for the animal experiments was approved by the ethics committee for animal experiments of the Catholic University of Leuven, Belgium. The part of the study involving human subjects was approved by the Ethical Committee of the Catholic University Leuven and performed in accordance with the Declaration of Helsinki.
Provenance and peer review Not commissioned; externally peer reviewed.