Urinary Concentrations of Eosinophil-Derived Neurotoxin in Children with Atopic Dermatitis

Abstract

Atopic Dermatitis (AD) is a clu•onic relapsing inflammatory skin disease. It is often the first step in the allergic march that results in asthma and allergic rhinitis. It is characterized by cutaneous hyperactivity to environmental triggers that are innocuous to non-atopic individuals. There is increasing evidence that frequency of atopic diseases including AD has increased worldwide over the last few decades with prevalence rates ranging between 10-20%.

There is strong evidence that eosinophils play a role in the pathogenesis of AD, especially in chronic lesions. Deposition of extracellular eosinophil granule proteins, such as ECP and EDN, in affected skin suggests that degranulation of eosinophils has occurred. In addition, several studies have shown an association between urinary EDN and disease activity in AD, indicating that granule proteins have escaped from the eosinophils as part of the disease process.

The eosinophil-derived neurotoxin (EDN) is one of the four major proteins found in the cytoplasmic granules of human eosinophilic leukocytic cells and has been suggested to be a useful marker of eosinophilic inflammation.