Cord Blood Serum Levels of IL-31 and CCL17, Cutaneous Markers, and Development of Atopic Dermatitis.

Importance: Atopic dermatitis (AD) is the most prevalent chronic skin condition characterized by inflammation and itching. Currently, there is no reliable method for identifying which newborns might have an increased risk of developing AD.

Objective: To evaluate the predictive value of serological biomarkers, such as CCL17/thymus- and activation-regulated chemokine, CCL18, CCL22, CCL27, IL-31, and thymus stromal lymphopoietin, with transepidermal water loss (TEWL) and hydration rate and the development of AD in infants.

Design, Setting, And Participants: This observational prospective study included 40 consecutive full-term newborns from a single university hospital in Pisa, Italy. The cutaneous markers of infants were assessed at 1, 6, and 12 months of age, while the biomarkers from the 10-mL sample of cord blood taken at birth were measured after delivery. Data were collected from March to December 2018 and analyzed from January to April 2019.

Main Outcomes And Measures: Level of serological biomarkers associated with TEWL and hydration rate, as well as the emergence of AD during the first 12 months of life.

Results: All 40 included infants (27 male [68%]) completed the study. At 6 months, 16 infants presented symptoms and signs of AD (AD group) and 24 did not (non-AD group). Infants with AD signs had statistically significant anterior cubital fossa TEWL values at 1, 6, and 12 months of age compared to those without AD signs. No statistically significant correlations were observed between the TEWL measured at the anterior part of knee and hydration rate at the anterior cubital fossa at first month in the 2 groups. With regard to the blood biomarkers, at birth those in the AD group vs the non-AD group had statistically significant higher levels of CCL17/thymus- and activation-regulated chemokine (median [IQR], 716 [509-951] pg/mL vs 419 [24-566] pg/mL; P = .003) and IL-31 (median [IQR], 212 [114-409] pg/mL vs 97 [52-277] pg/mL; P = .04); in contrast, no statistically significant serum level differences were registered for thymus stromal lymphopoietin (median [IQR], 105 [66-295] pg/mL vs 88 [43-187] pg/mL), CCL18 (median [IQR], 1236 [1115-1605] pg/mL vs 1255 [1188-1677] pg/mL), CCL22 (median [IQR], 1032 [936-1454] pg/mL vs 1096 [932-1536] pg/mL), and CCL27 (median [IQR], 172 [122-251] pg/mL vs 120 [90-265] pg/mL).

Conclusions And Relevance: In this observational study, the analysis of TEWL at the anterior cubital fossa area occurred prior to and correlated with the clinical signs of AD. Quantification of cytokines indicated that assessing cord blood serum levels of CCL17 and IL-31 could offer new perspectives in identifying newborns who might be susceptible to AD. Larger studies are needed to validate these findings.