Intrinsically defective skin barrier function in children with atopic dermatitis correlates with disease severity.

BACKGROUND: Recent genetic evidence supports that an underlying defect in skin barrier function contributes to the pathogenesis of atopic dermatitis (AD). The integrity of the skin barrier can be assessed objectively by measuring transepidermal water loss (TEWL). Previous investigations of TEWL as a biomarker of skin barrier function have been limited by small sample size, and studies including African American subjects are lacking. OBJECTIVE: We sought to determine whether children with AD have inherently altered skin barrier function by comparing TEWL as a measure of skin barrier function in African American and white children with AD with that in control subjects without AD. METHODS: TEWL was measured on nonlesional normal-appearing skin at 4 sites (the volar forearm, dorsal arm, lower leg, and cheek) in (1) children with AD (cases), (2) children with asthma or allergic rhinitis but without AD (allergic control subjects), and (3) nonatopic control subjects. AD severity was assessed by using the objective SCORAD index. RESULTS: TEWL was increased in children with AD compared with that seen in both control groups at most of the anatomic sites tested (P < .05). TEWL also correlated with objective SCORAD score. The presence of allergic sensitization or other allergic conditions did not affect TEWL among children with AD. TEWL was higher in white than in African American children. CONCLUSION: Skin barrier function as assessed by TEWL is intrinsically compromised in children with AD but not in children with other allergic conditions. The magnitude of skin barrier dysfunction correlates with AD disease severity.

Aeroallergen sensitization in healthy children: racial and socioeconomic correlates.

OBJECTIVE: Allergic sensitization is very prevalent and often precedes the development of allergic disease. This study examined the association of race with allergic sensitization among healthy children with no family history of atopy. STUDY DESIGN: Two hundred seventy-five children, predominantly from lower socioeconomic strata, from Cincinnati, Ohio, ages 2 to 18 years without a family or personal history of allergic diseases, underwent skin prick testing to 11 allergen panels. The Pediatric Allergic Disease Quality of Life Questionnaire (PADQLQ) was used to examine the impact of sensitization on quality of life. RESULTS: Thirty-nine percent of healthy children were sensitized to 1 or more allergen panels. Multivariate logistic regression showed increased risk among African-American children for any sensitization (OR, 2.17; [95% CI: 1.23, 3.84]) and sensitization to any outdoor allergen (OR, 2.96 [95% CI: 1.52, 5.74]). Eighty-six percent of children had PADQLQ scores of 1 or less (0 to 6 scale). CONCLUSIONS: Allergic sensitization is prevalent even among children who do not have a personal or family history of asthma, allergic rhinitis, or atopic dermatitis and who have no evidence of current, even subtle effects from this sensitization on allergic disease-related quality of life. African-American children are at greater risk for presence of sensitization, especially to outdoor allergens.