Atopic Dermatitis in Children: Differential Diagnosis and Mimickers.

Background: Atopic dermatitis (AD) is a chronic, relapsing inflammatory dermatosis that is characterized by pruritus, xerosis, and age-dependent clinical heterogeneity. Accurately diagnosing AD remains challenging due to the absence of specific biomarkers and the broad spectrum of conditions that may mimic its presentation. A wide range of inflammatory, infectious, and genetic disorders resemble AD, including seborrheic dermatitis, psoriasis, contact dermatitis, scabies, dermatophytosis, and nummular eczema, as well as rare immunodeficiency and metabolic conditions. This review summarizes the evolution of the clinical features of pediatric AD across infancy, childhood, and adolescence, with a focus on key differential diagnoses. Recognizing age-specific patterns and potential mimickers is essential for improving diagnostic accuracy and guiding appropriate management in pediatric AD. Methods: This study was designed as a narrative review. A structured literature search was conducted of PubMed/MEDLINE for studies published between January 2001 and March 2026 using predefined keywords related to AD, childhood, diagnosis, and differential. Clinical trials, randomized controlled trials, systematic reviews, meta-analyses, and guidelines or consensus documents were included. Studies focusing exclusively on adults or lacking clinical relevance were excluded. A qualitative synthesis was performed due to the heterogeneity in study designs and outcomes. Results: This review demonstrates that pediatric atopic dermatitis exhibits marked age-dependent clinical heterogeneity, with distinct morphological features and lesion distribution patterns across infancy, childhood, and adolescence. Furthermore, the substantial clinical overlap with a broad spectrum of inflammatory, infectious, and genetic disorders-combined with the absence of specific diagnostic biomarkers-significantly complicates accurate differential diagnosis and increases the risk of misclassification. Conclusions: The recognition of age-specific patterns and potential mimickers is essential for improving diagnostic accuracy and guiding appropriate management in pediatric AD.