Atopic Dermatitis (AD) and Food Allergy

Inclusion Criteria:

Participants fulfilling all of the following criteria are eligible for enrollment-

-Parent/guardian must be able to understand and provide informed consent and participant provide assent as applicable per Institutional Review Board (IRB) guidelines and regulations;

For Eligibility to One of the Two Active Atopic Dermatitis (AD) Groups:

-Active Atopic Dermatitis (AD) without a history or current manifestations of eczema herpeticum (EH), as diagnosed using the Atopic Dermatitis Registry

Network (ADRN) Standard Diagnostic Criteria and food allergy to peanut. Participant must meet all of the following criteria:

• Self-report or documentation of a positive oral food challenge to peanut or self-report of an allergic reaction to peanut within 2 hours of ingestion
• Peanut skin prick test wheal ≥ 8 mm. OR -Active AD without a history or current manifestations of EH, as diagnosed using ADRN Standard Diagnostic Criteria and no food allergy.

Participant must meet all of the following criteria:

• No personal history or current manifestations of food allergy (based on no self-report of a positive oral food challenge, positive skin test, positive blood test, or allergic reactions).
• Negative skin prick test (wheal < 3 mm) to peanut, milk, egg, wheat, soy, shellfish mix, tree nuts, and sesame seed.

For Non-atopic (NA) Group Eligibility:

Participant must meet all of the following criteria:

• No personal history or current manifestations of AD, asthma, or allergic rhinitis (based on self-report);
• No personal history or current manifestations of food allergy (based on no self- report of a positive oral food challenge, positive skin test, positive blood test, or allergic reactions);
• Negative skin prick test (wheal < 3 mm) to peanut, milk, egg, wheat, soy, shellfish mix, tree nuts, and sesame seed; and
• Negative skin prick test (wheal < 3 mm) to environmental allergens (cat, dog, dust mite, cockroach, and local trees/grasses/weeds/molds).

Exclusion Criteria:

• Inability or unwillingness of a parent/guardian to give written informed consent, or participant to give assent, if applicable, or to comply with study protocol;
• Subjects with skin disease other than AD that might compromise the stratum corneum barrier (e.g., bullous diseases, psoriasis, cutaneous T cell lymphoma [also called Mycosis Fungoides or Sezary syndrome], dermatitis herpetiformis, Hailey- Hailey, or Darier's disease);
• Pregnant or lactating females;
• Known or suspected immunosuppression;
• Severe concomitant illness(es);
• History of serious life-threatening reaction to latex, tape, or adhesives;
• 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;
• Use of biologics within 5 half-lives (if known) or 16 weeks of the Screening Visit;
• Use of an investigational drug within 5 half-lives (if known) or 8 weeks of the Screening Visit; or
• Has received immunotherapy within 12 months of the Screening Visit.