Lipidomics Profile Change of Skin Surface Lipids in Nummular Eczema

Nummular eczema (NE), first introduced by Devegie in 1857, is chronic dermatitis characterized by oval or coin-shaped lesions with distinct boundaries, usually accompanied by severe pruritus ( Leung et al., 2020 Leung A.K.C. Lam J.M. Leong K.F. Leung A.A.M. Wong A.H.C. Hon K.L. Nummular eczema: an updated review. Recent Pat Inflamm Allergy Drug Discov. 2020; 14: 146-155 Crossref PubMed Scopus (13) Google Scholar ). Although its pathophysiological characteristics are still scarcely available, various factors have been reported to be implicated such as nutrition, infection, alcohol intake, dry skin, contact irritation, and sensitivity ( Bonamonte et al., 2012 Bonamonte D. Foti C. Vestita M. Ranieri L.D. Angelini G. Nummular eczema and contact allergy: a retrospective study. Dermatitis. 2012; 23: 153-157 Crossref PubMed Scopus (41) Google Scholar ). Besides controlling inflammation, management is aimed at reducing skin dryness and restoring the skin barrier, which improves xerosis and irritation ( Leung et al., 2020 Leung A.K.C. Lam J.M. Leong K.F. Leung A.A.M. Wong A.H.C. Hon K.L. Nummular eczema: an updated review. Recent Pat Inflamm Allergy Drug Discov. 2020; 14: 146-155 Crossref PubMed Scopus (13) Google Scholar ). Stratum corneum (SC) serves as an essential skin barrier, consisting of a network of corneocytes and a lipid-rich extracellular matrix (brick and mortar). Either protein defect or aberrant lipid profile is usually a cause of dysfunctional SC ( Murphrey et al., 2022 Murphrey M.B. Miao J.H. Zito P.M. Histology, stratum corneum. in: StatPearls [Internet]. StatPearls Publishing, Treasure Island, FL2022 Google Scholar ).