A New Suite of Diagnostic Tools for EGIDs

One of several probes in development at Vanderbilt to help diagnose eosinophilic gastrointestinal disorders.
A New Suite of Diagnostic Tools for EGIDs
One of several probes in development at Vanderbilt to help diagnose eosinophilic gastrointestinal disorders.
Research puts innovative focus on earlier, more tolerable interventions.

Currently, ongoing evaluation of children’s eosinophilic gastrointestinal disorders (EGIDs) requires repeated endoscopies and biopsies. This is time consuming, expensive, and stressful for the patient, but it is necessary to identify and treat EGIDs before they cause potentially irreversible tissue damage and fibrosis.

The most common EGID, eosinophilic esophagitis (EoE), is increasingly recognized among children and adults. “It appears to be a manifestation of an allergy to foods, or less commonly, to aero-allergens,” said Sari Acra, M.D., Division Chief of Pediatric Gastroenterology, Hepatology and Nutrition at Monroe Carell Jr. Children’s Hospital at Vanderbilt.

At Vanderbilt, pediatric gastroenterologists are working to improve the evaluation of EoE and other EGIDs after initial diagnosis through a robust clinical and research program led by Girish Hiremath, M.D. The team’s current focus is on advances that could help children and their families avoid the stress of repeated endoscopies and biopsies.

Toxic Consequences 

In EoE, an allergy-triggering substance enters the esophagus prompting an excessive quantity of eosinophils to migrate to the affected area, releasing large quantities of toxins, Hiremath explained. Chronic inflammation and tissue damage from EoE can lead to fibrous scarring and difficulty swallowing. As EoE enters the fibrotic stage, adult patients may require regular esophageal dilation.

“It can be difficult to distinguish EoE from other conditions that affect the esophagus, such as gastroesophageal reflux disease, GERD,” Hiremath said. “More convenient and accurate diagnostic tools for EGIDs could lead to more patients being diagnosed before irreversible tissue damage takes place.”

“Our research is not just about diagnosing the disease – it’s also about figuring out what resources the families need to overcome it.”

Novel Technologies Ease Procedures

One promising diagnostic tool under investigation is a novel, non-invasive fiber-optic Raman spectroscopy probe. Hiremath and colleagues are testing if the probe could identify unique signatures for EoE, GERD, and proton pump inhibitor therapy-responsive esophageal eosinophilia, enabling more accurate differential diagnosis. Acra is also repurposing probe technology Vanderbilt developed for adult GI patients to detect electrical resistance in the esophagus. By touching the surface of the esophagus, the technology measures mucosal impedance to reveal the level of tissue inflammation. Others at Vanderbilt are exploring the utility of peroral endoscopic myotomy (POEM) for diagnosing esophageal disorders.

Finally, the researchers are exploring the prospect that changes in the salivary microbiome play a role in EoE pathobiology and could be a marker of the disease. Work by Hiremath, Acra and others found pediatric patients with EoE have more Haemophilus species in their saliva, along with lower microbial richness and diversity.

Hiremath says these new diagnostic technologies could also contribute to understanding of the pathophysiology of EGIDs. Raman spectroscopy, for example, could lead to insights into biochemical changes that drive disease evolution from an inflammatory to a fibrostenotic phenotype.

Improving Care for Patients and Families

Acra says that along with introducing tools to make procedures more comfortable, the Vanderbilt program remains focused on the broad picture for patients and their families. “Our research is not just about diagnosing the disease – it’s also about figuring out what resources the families need to overcome it.”

The team recently shed light on the difficult experiences of patients with EGIDs and their caregivers in a survey-based study. “This study is an important first step in addressing the gap in medical and emotional support for patients and caregivers of those affected by EGIDs,” Hiremath said.