Mixed Tree Nut Food Challenges

The purpose of this prospective study is twofold: 1) to establish oral tolerance to selected tree nuts and to examine potential predictors of oral tolerance and 2) to determine the usefulness of mixed tree nut allergen food challenges in more efficiently defining tree nut allergy and oral tolerance.

Study Overview

• Status: Unknown
• Conditions: Food Allergy

Detailed Description

To evaluate the absence of tree nuts (TN) allergy, referred patients from one of the Arkansas Children's Hospital (ACH) Allergy Clinic physicians with current serum immunoglobulin E (IgE) to TNs that meet eligibility criteria will be invited to undergo a series of open mixed TN food challenges.

A questionnaire pertaining to their TN allergy will be administered

A brief physical exam will be performed.

Skin prick tests using selected nut allergen extracts along with a positive (histamine) and a negative (salt-water) control will be performed at the first oral food challenge visit.

Each food challenges will be performed to 1 to 3 TNs.

Two telephone follow-up phone calls will evaluate inclusion/exclusion of tree nuts in the diet post food challenge.

• Study Type: Observational
• Enrollment (Anticipated): 100

Contacts and Locations

Study Locations

• United States
  • Arkansas
    • Little Rock, Arkansas, United States, 72202
      • Arkansas Children's Hospital

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 3 years to 21 years (Child, Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

• Sampling Method: Non-Probability Sample

Study Population

Patients seen at Arkansas Children's Hospital between 3-21 years of age who have tree nut food allergies.

Description

Inclusion Criteria:

• Any patient between 3-21 years of age followed by the Allergy and Immunology Department at Arkansas Children's Hospital on tree nut avoidance diet.
• Has current serum IgE test within the past 12 months to major nuts in question. All TN serum IgE are <10
• Children must have a stable baseline examination prior to undergoing challenge without significant symptoms of atopic dermatitis, allergic rhinoconjunctivitis, current urticaria or other allergic symptoms deemed important by the physician.
• Children must have stable asthma and no wheezing or repetitive cough prior to challenge, nor have been treated with oral steroids for a significant asthma exacerbation within 1 month of challenge. Asthmatics that undergo lung function testing.
• Children must have no current illness (e.g., fever or viral illness) at time of challenge.
• The subject will be asked to restrict the use of antihistamines (short acting, 72 hours: long acting, 5-7 days), (B-agonists (12 hours), theophylline (12 hours), and cromolyn (12 hours) prior to the first mixed TN food challenge. Other medications may be continued.

Exclusion Criteria:

• Any TN serum IgE ≥10.
• Life-threatening reaction (respiratory involvement requiring medications, or shock, or gastrointestinal reaction requiring intravenous fluids) to any TN.
• History of a reaction in the past year or severe reaction in the past 2 years or a history of a severe reaction anytime with a TN serum IgE >5
• Unstable asthma, gastrointestinal disease, cardiovascular disease, chronic lung disease, beta-blocker use.

Study Plan

How is the study designed?

Design Details

• Observational Models: Other
• Time Perspectives: Prospective

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Oral tolerance to selected tree nuts (TN) to determine potential predictors of oral tolerance.	This prospective, observational study uses serum IgE to specific TN, skin prick test to TN, and TN oral food challenges to establish oral tolerance.	total -20 years

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Use of tree nut (TN) IgE testing to assess the risk of positive food challenges based on grouped mixed TN food challenges	We postulate that by grouping TN that are mixed into one food challenge based on the individual's TN serum IgE will be more efficient in defining TN allergy and tolerance. One to three TNs will be in one food challenge based on TN IgE testing.	total - 20 years

Collaborators and Investigators

• Sponsor: Arkansas Children's Hospital Research Institute
• Investigators: Principal Investigator: Stacie M Jones, MD, University of Arkansas for Medical Sciences / Arkansas Children's Hospital

Study record dates

Study Major Dates

• Study Start: April 1, 2009
• Primary Completion (Anticipated): December 1, 2020
• Study Completion (Anticipated): December 1, 2020

Study Registration Dates

• First Submitted: August 8, 2013
• First Submitted That Met QC Criteria: February 21, 2014
• First Posted (Estimate): February 25, 2014

Study Record Updates

• Last Update Posted (Actual): January 10, 2019
• Last Update Submitted That Met QC Criteria: January 9, 2019
• Last Verified: January 1, 2019

More Information

Terms related to this study

• Keywords: Food allergy; Tree nuts
• Additional Relevant MeSH Terms: Immune System Diseases; Hypersensitivity, Immediate; Hypersensitivity; Food Hypersensitivity
• Other Study ID Numbers: 110035

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: Undecided
• IPD Plan Description: Data has not been analyzed at thistime