Abstract
Evaluation of: Sugiyama M, Arakawa H, Ozawa K et al. Early-life risk factors for occurrence of atopic dermatitis during the first year. Pediatrics 119(3), 716–723 (2007).
The pathogenesis of atopic dermatitis (AD) involves the interaction between environmental aeroallergens and immune-mediated skin hypersensitivity, in which preceding skin barrier dysfunction has been speculated to facilitate the permeation of large molecular aeroallergens into the skin. The paper under evaluation presents a prospective birth cohort study that planned to search for perinatal predictors of infantile AD. Fetal cord blood analyses for cytokines have demonstrated a negative relationship between the concentration of macrophage inflammatory protein-1β and later AD development, which seems to be compatible with the reported decrease of macrophage inflammatory protein-1β production by both CD4+ and CD8+ T cells under the dominance of Th2 responses over Th1 responses. However, no reduced stratum corneum (SC) hydration has been found in those babies before AD development, despite the recently discovered mutations in the gene encoding filaggrin in ichthyosis vulgaris and AD patients. In addition to the commentary on this paper, the key focus of this article is to discuss the commonly held confusion of decreased SC hydration with skin barrier impairment, as they constitute different SC dysfunctions. Both factors, but in particular dry skin, exert an exacerbating but not causative effect on AD.
Financial & competing interests disclosure
The author has no relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript. This includes employment, consultancies, honoraria, stock ownership or options, expert testimony, grants or patents received or pending, or royalties.
No writing assistance was utilized in the production of this manuscript.