Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Biopsies may overlook esophagus disease

07.09.2012
Study reveals limitations in detecting allergic disorder

University of Utah engineers mapped white blood cells called eonsinophils and showed an existing diagnostic method may overlook an elusive digestive disorder that causes swelling in the esophagus and painful swallowing.


These are microscope images of tissue from the esophagus of a patient with a disease named eosinophilic esophagitis, or EoE. The bar graphs around each image depict the number of white blood cells called eosinophils along the perimeter of each tissue sample. The cells eat away at the lining of the esophagus to cause the disorder. A University of Utah study suggests that the current method of diagnosing EoE by taking tissue samples with an endoscope may lead to under- or misdiagnosis of the disease.

Credit: Hedieh Saffari, University of Utah, for the Journal of Allergy and Clinical Immunology.

By pinpointing the location and density of eosinophils, which regulate allergy mechanisms in the immune system, these researchers suggest the disease eosinophilic esophagitis, or EoE, may be under- or misdiagnosed in patients using the current method, which is to take tissue samples (biopsies) with an endoscope.

These findings are published as the cover article in the September 2012 issue of the Journal of Allergy and Clinical Immunology. Despite the limitations of current detection methods for EoE, the study authors say biopsies remain the current standard of care, but the engineers are working toward new diagnostic methods that could be available in five years.

In EoE, eosinophils typically found in the bloodstream invade the esophagus and start chewing away at its lining. Often triggered by food allergies, EoE symptoms overlap with other disorders such as acid reflux.

"The gold standard for understanding this disease is detecting the location and presence of eosinophils in the esophagus. Unfortunately, eosinophils are not uniformly distributed within the esophagus, which can lead to underdiagnosis," says study co-author Leonard Pease, assistant professor of chemical engineering at the University of Utah. He is also an adjunct professor of gastroenterology and pharmaceutics.

The University of Utah team showed that even a patient with known EoE would require more than 31 random tissue samples, or biopsies, from an area in the esophagus with low eosinophil density to reliably diagnose EoE. Currently, if a patient is suspected of having EoE, five to 12 biopsies are collected along the esophagus using an endoscope. If more than 15 eosinophils turn up in any one of these samples, a diagnosis of EoE is made.

"This is the first quantitative assessment of how eosinophils are distributed in the esophagus," says co-author Gerald Gleich, professor of dermatology at the University of Utah and specialist in eosinophil-related diseases. "Until now, someone would go in and snip around, but they wouldn't have this map to quantify the degree of infiltration of this disease in relationship to the actual anatomy. These findings impact how many biopsies a doctor should perform."

Since eonsinophils are scattered within the esophagus, EoE can go undetected until severe symptoms surface, ranging from painful swallowing to chest pains that mimic a heart attack.

"This is not the ideal way to diagnose EoE," says Pease. "If the distribution of eosinophils was 100 percent uniform, it wouldn't matter where you sample, but in fact it's patchy. Our mapping shows if you sample in one region, no diagnosis would be made, but if you took another region about an inch away, the same patient would appear to be severely diseased."

To generate a map of eosinophil distribution in the esophagus, lead author Hedieh Saffari examined each of 17 tissue sections taken at intervals every one-eighth to one-fifth of an inch along the esophagus of a known adult EoE patient. A typical adult esophagus is 10 inches long.

"For every cross section, I used microscopy to count the number of eosinophil cells along the entire perimeter of the tissue surface in each high-power field of view image," said Saffari, a chemical engineering graduate student. "There were somewhere between 40 and 120 of these images per cross section so it took a lot of time, but it was worth it to extract the information we were looking for. No one has done this type of mapping before."

Saffari's diligence paid off. With her painstakingly collected data, she and Pease used a statistical simulation technique to determine whether randomly sampling tissue would result in a positive diagnosis of EoE based on eonsinophil density.

"Our analysis shows that with current diagnostic conventions, you are only going to catch the patients with medium-to-high eonsinophil densities, which means we may be misdiagnosing patients as much as one out of every five times," says Pease. "Given this data, clearly endoscopy is not sufficient for a disease this patchy."

Gleich says their findings will inform future revisions of EoE diagnosis guidelines, but biopsies are "currently the standard of care and will not change in the near future."

Building on this study, Pease and Saffari are investigating technologies for labeling and detecting proteins shed by eosinophils in the esophagus, which would help detect EoE at an earlier stage. They have also filed a patent to use radiolabeled antibodies to map eosinophils throughout the entire esophagus, a new technique that would be evaluated with a clinical trial. "We're optimistic that such a diagnostic tool could be available in the next five years," Pease says.

Saffari adds this is part of the team's long-term goal to develop new strategies to enhance EoE diagnosis and understand what causes the disease.

Pease, Gleich and Saffari conducted the study with gastroenterologists Kathryn Peterson and John Fang and pathologist Carolin Teman at the University of Utah. This study was funded by the University of Utah, the Utah Governor's Office of Economic Development and the National Science Foundation.

University of Utah College of Engineering
72 S. Central Campus Dr., Room 1650 WEB, Salt Lake City, UT 84112
(801) 581-6911 fax: (801) 581-8692

Aditi Risbud | EurekAlert!
Further information:
http://www.utah.edu
http://www.coe.utah.edu

More articles from Health and Medicine:

nachricht Unique brain 'fingerprint' can predict drug effectiveness
11.07.2018 | McGill University

nachricht Direct conversion of non-neuronal cells into nerve cells
03.07.2018 | Universitätsmedizin der Johannes Gutenberg-Universität Mainz

All articles from Health and Medicine >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: First evidence on the source of extragalactic particles

For the first time ever, scientists have determined the cosmic origin of highest-energy neutrinos. A research group led by IceCube scientist Elisa Resconi, spokesperson of the Collaborative Research Center SFB1258 at the Technical University of Munich (TUM), provides an important piece of evidence that the particles detected by the IceCube neutrino telescope at the South Pole originate from a galaxy four billion light-years away from Earth.

To rule out other origins with certainty, the team led by neutrino physicist Elisa Resconi from the Technical University of Munich and multi-wavelength...

Im Focus: Magnetic vortices: Two independent magnetic skyrmion phases discovered in a single material

For the first time a team of researchers have discovered two different phases of magnetic skyrmions in a single material. Physicists of the Technical Universities of Munich and Dresden and the University of Cologne can now better study and understand the properties of these magnetic structures, which are important for both basic research and applications.

Whirlpools are an everyday experience in a bath tub: When the water is drained a circular vortex is formed. Typically, such whirls are rather stable. Similar...

Im Focus: Breaking the bond: To take part or not?

Physicists working with Roland Wester at the University of Innsbruck have investigated if and how chemical reactions can be influenced by targeted vibrational excitation of the reactants. They were able to demonstrate that excitation with a laser beam does not affect the efficiency of a chemical exchange reaction and that the excited molecular group acts only as a spectator in the reaction.

A frequently used reaction in organic chemistry is nucleophilic substitution. It plays, for example, an important role in in the synthesis of new chemical...

Im Focus: New 2D Spectroscopy Methods

Optical spectroscopy allows investigating the energy structure and dynamic properties of complex quantum systems. Researchers from the University of Würzburg present two new approaches of coherent two-dimensional spectroscopy.

"Put an excitation into the system and observe how it evolves." According to physicist Professor Tobias Brixner, this is the credo of optical spectroscopy....

Im Focus: Chemical reactions in the light of ultrashort X-ray pulses from free-electron lasers

Ultra-short, high-intensity X-ray flashes open the door to the foundations of chemical reactions. Free-electron lasers generate these kinds of pulses, but there is a catch: the pulses vary in duration and energy. An international research team has now presented a solution: Using a ring of 16 detectors and a circularly polarized laser beam, they can determine both factors with attosecond accuracy.

Free-electron lasers (FELs) generate extremely short and intense X-ray flashes. Researchers can use these flashes to resolve structures with diameters on the...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Leading experts in Diabetes, Metabolism and Biomedical Engineering discuss Precision Medicine

13.07.2018 | Event News

Conference on Laser Polishing – LaP: Fine Tuning for Surfaces

12.07.2018 | Event News

11th European Wood-based Panel Symposium 2018: Meeting point for the wood-based materials industry

03.07.2018 | Event News

 
Latest News

Leading experts in Diabetes, Metabolism and Biomedical Engineering discuss Precision Medicine

13.07.2018 | Event News

Research finds new molecular structures in boron-based nanoclusters

13.07.2018 | Materials Sciences

Algae Have Land Genes

13.07.2018 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>