Phenotypes and Natural Course of Atopic Dermatitis: A Pathway to the Atopic March

INTRODUCTION: Atopic dermatitis (AD) is a chronic inflammatory skin disorder that may progress to asthma and/or allergic rhinitis (AR) in children, a progression known as the "atopic march." METHODS: This study aimed to evaluate the natural history of AD, its clinical phenotypes, and the risk of progression to atopic march over a 10-year period. A retrospective review of medical records was performed for children diagnosed with AD and those with respiratory allergies who had prior AD. Patients were categorized into early transient, early persistent, and late-onset phenotypes based on eczema onset age and disease course. Disease progression, atopic march development, and related risk factors were analyzed. RESULTS: The study included 894 children (375 females, 519 males) with a mean presentation age of 3.54 ± 3.31 years, mean follow-up of 3.65 ± 2.84 years. Based on clinical phenotypes, 61% (n = 545) were early transient, 15.2% (n = 136) early persistent, and 23.8% (n = 213) late-onset. Asthma and AR rates were 8.6-11.2% in early transient, 14.0-22.8% in early persistent, and 16.0-24.9% in late-onset phenotypes, respectively. Overall, 29.9% (n = 267) exhibited the atopic march; 56.3% (n = 503) were in remission; and 43.7% (n = 391) had persistent AD. Aeroallergen sensitization was significantly associated with persistent disease (p = 0.016) and atopic march progression (p = 0.001). Family history of atopy correlated with disease persistence (p = 0.033). CONCLUSION: Nearly one-third of children with AD are at risk of developing additional allergic diseases constituting the atopic march. Children with AD who exhibit aeroallergen sensitization should be closely monitored for the development of respiratory allergies.