aard Allergy, Asthma & Respiratory Disease Allergy Asthma Respir Dis 2288-0402 2288-0410 The Korean Academy of Pediatric Allergy and Respiratory Disease; The Korean Academy of Asthma 10.4168/aard.2020.8.1.9 aard-8-9 Review Phenotypes and endotypes of atopic dermatitis: Clinical implications KimMinji 1 KimJihyun 2 3 Department of Pediatrics, Hallym University Dongtan Sacred Heart Hospital, Hallym University School of Medicine, Dongtan Department of Pediatrics, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul Korea Environmental Health Center for Atopic Diseases, Samsung Medical Center, Seoul Korea Correspondence to: Jihyun Kim https://orcid.org/0000-0001-8493-2881 Department of Pediatrics, Samsung Medical Center, Sungkyunkwan University School of Medicine, 81 Irwon-ro, Gangnam-gu, Seoul 06351, Korea Tel: +82-2-3410-3539, Fax: +82-2-3410-0805, E-mail: jhlovechild@gmail.com

This study was funded by the Environmental Health Center Project of the Ministry of Environment, Republic of Korea.

 01 2020 12 01 2020 8 1 9 14 30052019 06082019 06082019 Copyright © 2020 The Korean Academy of Pediatric Allergy and Respiratory Disease; The Korean Academy of Asthma, Allergy and Clinical Immunology 2020 This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/3.0/) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited. Abstract

Atopic dermatitis (AD) is the most common chronic inflammatory skin disease, characterized by a complex pathophysiology and a variety of clinical phenotypes. However, heterogeneous clinical phenotypes are generally not considered in treating AD. To date, phenotypes and endotypes have been proposed to classify AD mainly based on differences in age, IgE, severity, race, skin barrier dysfunction, immune (Th2/Th17/Th22) polarization, and skin microbiome. Various biologics to target polarized immune pathways, including dupilumab, have been newly developed for the personalized treatment of moderate-to-severe AD. Further understanding of AD pathophysiology and identification of novel biomarkers will not only allow clinically useful stratification of AD and but also achieve precision medicine for the prevention and treatment of AD.

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Overview of atopic dermatitis phenotypes and endotypes. Th, T-helper type; IFN, interferon; IL, interleukin; TSLP, thymic stromal lymphopoietin. S. aureus, Staphylococcus aureus.