Immune Basis and Clinical Implications of Threshold-based Phenotypes of Peanut Allergy

Exclusion Criteria

• •Inability or unwillingness of a participant to give written informed consent or comply with study protocol
• •Serum peanut-specific IgE antibody level \> 50 kUA/L
• •Recent (within the past 2 years) life-threatening (grade 3) anaphylactic reaction to peanut.
• •Any disorder in which epinephrine is contraindicated such as known hypertension or cardia rhythm disorders.
• •History of chronic disease requiring therapy (other than asthma, atopic dermatitis, rhinitis).
• •On a build-up phase of any allergen immunotherapy.
• •For those with a history of asthma, the following are assessed and any of the following is an exclusion (markers of current uncontrolled or moderate to severe asthma):
• •1. FEV1 value \<80% predicted (only for participants age 7 years or older and are able to perform spirometry)
• •2. ACT or cACT \< 20
• •3. \>Step 3 controller therapy as defined for children 0-4, 5-11 and \>=12 years of age by EPR-3 tables
• •4. Use of steroid medications in the following manners:
• •1. history of daily oral steroid dosing for \>1 month during the past year,
• •2. having 1 burst or steroid course within the past 6 months, or
• •3. having \>1 burst oral steroid course within the past 12 months.
• •5. Asthma requiring \>1 hospitalization in the past year for asthma or \>1 ED visit in the past 6 months for asthma, or any prior intubation/mechanical ventilation for asthma/wheezing.
• •6. When COVID related institutional restrictions on spirometry are in effect, spirometry will not be performed and peak flow will be used with 80% predicted as cut-off.
• •Gastrointestinal eosinophilic disorders, esophagitis, gastroenteritis.
• •Use of short-acting antihistamines (diphenhydramine, etc.) more than one time within 3 days prior to DBPCFC or skin testing.\*
• •Use of medium-acting antihistamines (hydroxyzine, loratadine, etc.) more than one time within 7 days of DBPCFC or skin testing.\*
• •Use of systemic steroid medications (IV, IM or oral) for indications other than asthma for \> 3 weeks within the past 6 months
• •Use of beta-blockers (oral), (ACE) inhibitors, angiotensin-receptor blockers or calcium channel blockers.
• •Participation in any trials of therapeutic interventions for food allergy in the past year.
• •Therapy with anti-IgE or other biologics, including within 1 year of enrollment.
• •Use of investigational drugs within 52 weeks of participation.
• •Allergy to all of the following: oat, rice, corn, tapioca.
• •Pregnancy
• •Past or current medical problems or findings from physical examination or laboratory testing that are not listed above, which, in the opinion of the investigator, may pose additional risks from participation in the study, may interfere with the participant's ability to comply with study requirements or that may impact the quality or interpretation of the data obtained from the study.
• •\*Any subject meeting these criteria during the visits can be rescheduled for the oral food challenge or prick skin testing.\*