Allergen Sensitization "Profiles" May Help Explain Differences between Moderate and Severe Atopic Dermatitis

Patients with moderate atopic dermatitis (AD) may have different immunoglobin E (IgE) reactivity “profiles” than those with severe cases, according to a study recently published in PLoS One.

The study sample was limited to adults, all of whom were examined at the Karolinska University Hospital in Stockholm with care taken to avoid the summer allergy season. Moderate and severe groupings were delineated according to the SCORAD index; 53 severe AD and 126 moderate AD patients were included, along with 43 patients with seborrheic eczema and 97 patients with no history of allergy or skin diseases, who were included as controls. Total and specific IgE to common allergens was measured in plasma using Phadiatop, ImmunoCap, micro-arrayed allergens, dot-blotted recombinant Malassezia sympodialis allergens, and immune-blotted microbial and human proteins.

92% of patients with severe AD and 83% of patients with moderate AD showed IgE reactivity. More specifically, cat allergies occurred most frequently, followed by pollen (birch and grass), and then the yeast M. sympodialis. Those with severe AD were significantly more likely to have allergic sensitivity to cats, dust mites, M. sympodialis, and others like Staphylocaccus aureus and human antigens; conversely, and surprisingly, no significant differences were found in reactivity to grass pollen. Notably, the “reactivity profile” of patients with severe AD was more aligned with a particular group of allergen molecules, more so than those with moderate AD or control subjects.

It is already well-known that allergens can trigger the symptoms of atopic dermatitis, but the potential emergence of allergen sensitization profiles that correspond specifically to moderate and severe AD holds promise for enhanced understanding and treatment of patients with the disease.

According to the researchers: “We have revealed a hitherto unknown difference regarding the molecular sensitization profile in patients with severe and moderate AD. Molecular profiling towards allergen components may provide a basis for future investigations aiming to explore the environmental, genetic and epigenetic factors which could be responsible for the different appearance and severity of disease phenotypes in AD.”