Skin Characteristics of Parents of Food Allergic Pediatric Patients

Skin Characteristics of Parents of Food Allergic Pediatric Patients

The purpose of this study is to determine whether disruptions in the skin barrier of parents can contribute to the development of food allergies in their offspring. The study team will compare the superficial skin layers of mothers and fathers who do not have children with diagnosed food allergies to the skin layers of parents who do have children with diagnosed food allergy. The study will include a questionnaire, noninvasive superficial skin testing with skin tapping and transepidermal water loss measurements, and a blood draw.

There is an already well-established link between atopic dermatitis (AD), or eczema, and the development of food allergies. More specifically, it is believed that sensitizations to food can occur through low-dose cutaneous sensitization via a disrupted skin barrier. The strongest genetic contributor to eczema is the FLG loss-of-function or missense mutation, which is associated with increased transepidermal water loss and increased skin permeability (1). In a recent study exploring the risk of maternal transmission of allergic risk, it was found that children of FLG-carrier mothers had a 1.5 increased AD risk, specifically when these mothers had allergic sensitization (elevated allergen-specific IgE antibody plasma levels) but independent of their own FLG mutation status (10). This information may suggest that an interrupted skin barrier in mothers may serve as an environmental risk factor for the development of food allergies in their offspring.

The purpose of our study is to evaluate the skin characteristics and FLG gene mutation status of parents of known food allergic pediatric patients. The researchers hypothesize that parents of food allergic patients will have more significant disruptions in their skin barrier function than parents of children who do not suffer from food allergies.

In order to evaluate skin barrier disruptions in these subjects, two noninvasive methods will be performed including skin tape stripping, a total of 30 strips per subject, and transepidermal water loss measurements using a small device. Both methods are relatively painless and cause minimal risk to the participant. In order to evaluated FLG gene mutation status, blood draw will also be performed. Subjects will undergo a focused physical exam and also be requested to fill out a detailed questionnaire. The researchers will obtain additional offspring peanut allergy clinical characteristics from the medical records. All data collection will occur over 1-2 visits, averaging an anticipated 1 hour in total duration.

Inclusion Criteria:

1. Subject has signed the informed consent form

2. 18 years of age or older (inclusive) 3. One of the following Diagnostic Categories:

   1. Normal healthy controls with no personal or offspring history of food allergy or atopic dermatitis
   2. Mother or father without personal history of food allergy, but with a child diagnosed with peanut allergy. Peanut allergy is defined as fulfilling one of the following 3 criteria:

   i. Clinical history defined as one of the following occurring within 2 hours of exposure to peanut:

   1. Involvement of the skin-mucosal tissue (eg, generalized hives, itch-flush, swollen lips-tongue-uvula)
   2. Respiratory compromise (eg, dyspnea, wheeze-bronchospasm, stridor, reduced PEF, hypoxemia)
   3. Reduced BP or associated symptoms (eg, hypotonia [collapse], syncope, incontinence)
   4. Persistent gastrointestinal symptoms (eg, crampy abdominal pain, vomiting)

ii. Positive skin prick testing > 8 mm

iii. Positive specific IgE to peanut > 14.0 kUA/L

Exclusion Criteria:

1. Has active flare of atopic dermatitis requiring use of bleach baths, topical corticosteroids, topical immunomodulatory agents, or topical antibiotics on the extremity being evaluated
2. Has a skin disease other than AD that might compromise the stratum corneum barrier such as bullous disease, psoriasis, cutaneous T cell lymphoma, Darier's disease, HaileyHailey, or dermatitis herpetiformis
3. Has a current systemic infection requiring use of systemic antibiotics, antiparasitics, antivirals, or antifungals
4. Has a severe concomitant disease or immunosuppression such as lymphoma, HIV, or Wiskott-Aldrich syndrome
5. Has a history of a severe reaction to latex, tape, or adhesives
6. Has used any biologics within 5 half-lives or 16 weeks, whichever is longer
7. Has received immunotherapy in the last 12 months
8. Has used any investigational drugs within 5 half-lives or 8 weeks, whichever is longer
9. Has used anticoagulants, anxiolytics, or antidepressants within 30 days
10. Has used of systemic immunosuppressive drugs including oral steroids within 30 days
11. Has received total body phototherapy (e.g., ultraviolet light B [UVB], psoralen plus ultraviolet light A [PUVA], tanning beds [>1 visit per week]) within 30 days
12. Is pregnant or lactating (this will be self-verified by the patient)