The first assessment in pediatric patients of a recently developed mucosal impedance (MI) catheter shows that the tool has great promise as a safer and less invasive technique for assessing esophageal inflammation in children.

A study published in the Journal of Pediatric Gastroenterology and Nutrition in August 2018 found that MI measurements (measuring how resistant the esophageal lining is to the flow of a small electric current) can accurately determine whether a patient has active eosinophilic esophagitis (EoE) vs. inactive EoE, non-erosive reflux disease (NERD) or is disease-free.

The current standard for diagnosing EoE involves sedated endoscopy and typically requires at least 6 samples be evaluated in a lab.

The results of the MI study – conducted by Pediatric Gastroenterologists working in Monroe Carell Jr. Children’s Hospital at Vanderbilt – show that the identification of EoE can potentially be done with no biopsies and that the results can be provided immediately.

“The results from using this new device are really exciting,” said Sari Acra, M.D., professor of Pediatrics and Division Chief of Pediatric Gastroenterology at Vanderbilt University Medical Center. “We are really hopeful that with further refinements, this device will allow more timely, safer and cheaper monitoring of the disease and its response to therapy.”

New tool may help identify EoE patients ‘instantaneously’

The existing management strategy for EoE regularly requires patients to return every 2 to 4 months for sedated endoscopy until the disease is under control, which is expensive and inefficient. Endoscopic findings can also be normal in 7% to 33% of active EoE cases, underscoring the need for developing a more accurate way to determine EoE status.

The MI device used in the study, which measures the impedance of surface mucosa, contrasts with the more commonly used multichannel intraluminal impedance (MII) device, which measures changes due to food and fluid transitions in the esophagus and has been tested in pediatric patients with varying levels of success.

For the study, esophageal MI was measured in all patients at 2, 5, and 10 cm above the squamo-columnar junction (SJC). Kruskal-Wallis testing was used and confirmed that active-EoE patients had significantly lower MI measurements compared to inactive-EoE, NERD, and control groups.

“The impedance levels were distinctly lower in active EoE patients compared to inactive disease or other conditions, so that the measurements could easily and reliably identify patients with active EoE almost instantaneously,” said Acra.

“The results from using this new device are really exciting.”

The results of the MI measurements were consistent with those from histologic evaluations, which shows great evidence for its use in the future. The study’s authors suggested that histologic techniques would likely still be used at this time, but as the MI is refined it may become the technique of choice for determining active EoE.

The efficacy of the MI is especially exciting because if the MI is developed into a tool that does not require endoscopic placement, it could eventually eliminate the need for obtaining biopsies and repeat endoscopies when monitoring EoE activity. Significantly lowered risks and costs may be on the horizon with such a tool.

“In conjunction with the adult GI specialists at Vanderbilt, we are actively working on the next generation of these probes that will allow us to deploy them without endoscopy, and hope to be testing them in the very near future,” said Acra.

About the Expert

Sari Acra, M.D.

Sari Acra, M.D., M.P.H. is a professor of pediatrics and director of pediatric gastroenterology at Vanderbilt University Medical Center and Monroe Carell Jr. Children's Hospital at Vanderbilt. He is also director of the D. Brent Polk Division of Pediatric Gastroenterology, Hepatology, and Nutrition fellowship program at Vanderbilt. His research interests revolve around the field of nutrition, particularly the impact of alterations in caloric energy balance and body composition on human diseases.