Novel Blood Test to Predict Safe Foods for Infants and Toddlers With Food Protein-induced Enterocolitis Syndrome (FPIES)

University of Michigan10 enrolled

Overview

The aim of this study is to validate a blood test that can identify safe foods for food protein-induced enterocolitis syndrome (FPIES). This study proposes a solution to the problems of FPIES by developing a new blood assay that screens a large number of foods (more than 20) in a culture plate. If this blood test is successful it may be able to identify safe foods more quickly. The study will recruit 10 participants that will have more than 2 trigger foods.

Participants will complete surveys and have blood draws during the study. Additionally, participants will be asked to keep track of their diet as well as introduce safe foods identified by the researchers.

Study Type

INTERVENTIONAL

Allocation

Purpose

DIAGNOSTIC

Masking

NONE

Enrollment

Conditions

Food Protein-Induced Enterocolitis Syndrome Allergies Pediatric Disorder

Interventions

Eligibility

Sex: ALLMin age: 1 MonthMax age: 7 Years

Medical Language ↔ Plain English

Inclusion Criteria: * Diagnosis of FPIES * Have to have documented reactions to 2-3 trigger foods with recurrent delayed vomiting or documented reactions to 4 or more trigger foods with recurrent delayed vomiting. Exclusion Criteria: * Patients who are currently on medications that suppress the immune system * Patients who do not have at least 2 trigger foods identified. * Patients who have a history of an organic Gastrointestinal (GI) disease (e.g., inflammatory bowel disease, celiac disease, biliary disorders, bowel resection), cardiac, pulmonary, neurologic, renal, endocrine, or gynecological pathology * Lack of parental or guardian informed consent.

Outcomes

Primary Outcomes

Negative Predictive Value (NPV), Defined as the Percentage of Test-predicted Safe Foods That Are Actually Safe Foods.

A Receiver operating characteristic (ROC) curve was built to estimate the NPV. A random-effects logit model was used to model the binary outcome (safe or trigger food) as a function of the 9 biomarker measurements in the assay. (Expression Value = Relative fold change of 9-gene expression panel in response to food treatment, divided by fold change in response to LPS treatment, multiplied by 1000). The random effect in the logit model took into consideration the correlated data measured within the same subject. A cluster ROC curve analysis was used to assess the precision of the assay. Specifically, the area was computed under the cluster ROC curve (AUC). A threshold to obtain the NPV was selected based on inspection of the ROC curve. At the initial visit, participants had their blood drawn, which was assayed. On average, participants came in up to 4 weeks later after the test results were ready. Participants were then asked to trial a new food each week for up to 7 weeks.

Time frame: Up to 7 weeks from the first blood trial, on average 11 weeks

Secondary Outcomes

Positive Predictive Value (PPV), Defined as the Percentage of Test-predicted Unsafe Foods That Are Actually Unsafe Foods.

The same ROC curve described for the primary outcome was used to derive the PPV. At the initial visit, participants had their blood drawn, which was assayed. On average, participants came in up to 4 weeks later after the test results were ready. Participants were then asked to trial a new food each week for up to 7 weeks.