Influence of Atopic Dermatitis on the Dermoscopic Phenotype of Positive Patch Test Reactions: A Prospective Comparative Study

This study examined the impact of atopic dermatitis (AD) on the dermoscopic features of positive patch test reactions in 160 participants, equally divided between those with and without AD. It found that certain dermoscopic features, such as perifollicular erythema, yellowish areas, and pigment residuals, were more common in individuals with AD. For example, perifollicular erythema was significantly more prevalent in children with AD (41.9%) compared to non-AD controls (7.3%). Dermoscopy also helped reduce the number of clinically doubtful reactions, particularly in AD patients, by 59.5% in adults and 53.4% in children, suggesting its usefulness in improving diagnostic accuracy for patch test evaluations in those with AD.