Adhesive tape strips offer a ‘minimally invasive’ alternative to tell between the two skin conditions, instead of using skin biopsies, which can be painful, leave scars and carry risk of infection.
The study, published in the Journal of Allergy and Clinical Immunology, divided 60 participants into three groups: 20 with moderate to severe atopic dermatitis (or eczema), 20 with moderate to severe psoriasis, and 20 with no skin disorders.
Scientists from the Icahn School of Medicine applied tape strips for around five seconds to collect skin cells and then used molecular profiling to identify disease biomarkers.
They were able to perfectly differentiate between the two conditions using a single biomarker, called nitride oxide synthase 2.
Skin biopsies are particularly difficult to carry out in small children, so this could be an important development to diagnose those suffering from skin conditions at an early age.
When it is not easy to distinguish between atopic dermatitis and psoriasis, this can mean patients are put on the wrong medication, which can prolong symptoms.
However, a time-consuming RNA isolation process is needed to detect disease biomarkers.
Atopic dermatitis is an inflammatory, extremely itchy skin disorder that affects up to 15 million people in the UK and one in every five children at some point.
Psoriasis is a skin condition that causes red, flaky, crusty patches of skin covered with silvery scales, affecting around 2% of people in the UK.