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Use of Esophageal String Test to Understand Symptoms, Inflammation, and Function in Eosinophilic Esophagitis

Use of Esophageal String Test to Understand Symptoms, Inflammation, and Function in Eosinophilic Esophagitis

Status
Completed
Phases
NA
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT03305653
Enrollment
21
Registered
2017-10-10
Start date
2018-05-01
Completion date
2019-03-01
Last updated
2021-07-06

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Eosinophilic Esophagitis

Keywords

Pediatrics

Brief summary

Presently, the only method available to monitor disease activity in Eosinophilic Esophagitis (EoE) is endoscopy with pathological review of biopsies. The overall goal of this study is to determine the ability of the Esophageal String Test (EST), a minimally invasive capsule based technology, to measure disease activity in children with EoE. Additionally, to determine esophageal distensibility in children presenting with EoE by using the EndoFLIP (functional luminal imaging probe) device during endoscopic procedures.

Detailed description

When children are scheduled to undergo an endoscopy, research assistants will contact the family to arrange for the Esophageal String Test (EST) to be performed within one week of the endoscopy. The string test involves swallowing a small capsule with a thin piece of string inside it. The string unravels as the capsule goes down into the stomach. The investigator would tape the end of the string to the child's cheek, leaving it there for one hour. At the end of the hour, the investigator would remove the string by gently pulling it out through the mouth. Prior to swallowing the EST, the patient will complete the PEESS form (Pediatric Eosinophilic Esophagitis Symptom Scores) to assess symptoms. The endoscopy and Endoscopic Reference System (EREFs) and EndoFLIP will be performed. The EndoFLIP is a slender probe covered by a smooth long balloon that is passed into the esophagus and slowly expanded with a salt solution. After standard of care endoscopic visualization, the FLIP, a 16 cm probe (Crospon) will be placed transorally and positioned 3 cm distal to the lower esophageal sphincter. Esophageal cross sectional areas and intrabag pressure will be measured during stepwise distensions beginning with 5 mL and increasing to a maximum of 70mL or intrabag pressure of 50 mmHg is achieved, whichever comes first. FLIP is FDA-approved without age restriction and its use has been approved by our IRBs previously. Primary results will be reported as distensibility plateau (mm). Endoscopic severity: Endoscopic esophageal appearances will be scored using a validated EoE scoring system (EREFS). Five features of EoE will be scored: Edema (0-1), Rings (0-3) Exudates (0-2), Furrows (0-1), Stricture (0-1). Results will be reported as an inflammatory score (edema, exudates, furrows) and fibrostenotic score (rings, stricture). Functional Luminal Imaging Probe (FLIP):

Interventions

The EST is a gelatin capsule filled with a 90cm nylon string. A trailing end of the string protrudes from one end of the capsule. This end is taped to the cheek and the capsule is swallowed. As the capsule travels to the small intestine, the string inside the capsule is dislodged, leaving a string that goes from the cheek to the small intestine. The capsule dislodges from the string and the string is left in place, in the mouth, esophagus, stomach and small intestine for an hour. During this time, the string rubs against the inside of the esophagus and collects eosinophil proteins. After one hour, the string is removed through the mouth and placed in preservative to save the eosinophil proteins.

Sponsors

Children's Hospital of Philadelphia
CollaboratorOTHER
Children's Hospital Colorado
CollaboratorOTHER
University of Colorado, Denver
Lead SponsorOTHER

Study design

Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
BASIC_SCIENCE
Masking
NONE

Eligibility

Sex/Gender
ALL
Age
7 Years to 17 Years
Healthy volunteers
No

Inclusion criteria

* Provide signed and dated informed consent form. * Willing to comply with all study procedures and be available for the duration of the study. * Male or female, aged 7 to 18 years old, inclusive * Undergoing upper Endoscopy with biopsy for clinical care at CHCO or CHOP * Current or historical diagnosis of EoE, or suspected of having EoE

Exclusion criteria

* Known connective tissue disease, other eosinophilic disorders * Past history of caustic injestion, esophageal surgery or other esophageal injury * Known inflammatory bowel disease or esophageal motility disease (achalasia) * Unwilling or unable to swallow the EST * Oral or intravenous steroids in the preceding 60 days (not including swallowed topical fluticasone, budesonide, etc) * Pregnancy * Participation in a clinical study that may interfere with participation in this study

Design outcomes

Primary

MeasureTime frameDescription
Measurement of Eosinophilic Degranulating Protein ConcentrationMeasurement at one hour, when string is removedMeasure the concentration of eosinophilic degranulating protein on strings that have been swallowed by subjects diagnosed with EoE

Countries

United States

Participant flow

Participants by arm

ArmCount
Current/Historical Diagnosis of EoE
Subjects with current or historical diagnosis of EoE, or suspected of having EoE will complete the Esophageal String Test (EST) and EndoFLIP Esophageal String Test (EST): The EST is a gelatin capsule filled with a 90cm nylon string. A trailing end of the string protrudes from one end of the capsule. This end is taped to the cheek and the capsule is swallowed. As the capsule travels to the small intestine, the string inside the capsule is dislodged, leaving a string that goes from the cheek to the small intestine. The capsule dislodges from the string and the string is left in place, in the mouth, esophagus, stomach and small intestine for an hour. During this time, the string rubs against the inside of the esophagus and collects eosinophil proteins. After one hour, the string is removed through the mouth and placed in preservative to save the eosinophil proteins.
21
Total21

Baseline characteristics

CharacteristicCurrent/Historical Diagnosis of EoE
Age, Categorical
<=18 years
21 Participants
Age, Categorical
>=65 years
0 Participants
Age, Categorical
Between 18 and 65 years
0 Participants
Race/Ethnicity, Customized
Asian
2 Participants
Race/Ethnicity, Customized
Black
2 Participants
Race/Ethnicity, Customized
Hispanic
2 Participants
Race/Ethnicity, Customized
White
15 Participants
Region of Enrollment
United States
21 participants
Sex: Female, Male
Female
5 Participants
Sex: Female, Male
Male
16 Participants

Adverse events

Event typeEG000
affected / at risk
deaths
Total, all-cause mortality
0 / 21
other
Total, other adverse events
0 / 21
serious
Total, serious adverse events
0 / 21

Outcome results

Primary

Measurement of Eosinophilic Degranulating Protein Concentration

Measure the concentration of eosinophilic degranulating protein on strings that have been swallowed by subjects diagnosed with EoE

Time frame: Measurement at one hour, when string is removed

Population: Number of patients who completed swallowing the string

ArmMeasureValue (MEAN)
Current/Historical Diagnosis of EoEMeasurement of Eosinophilic Degranulating Protein Concentration456.5 ng/mL

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026