Although psoriasis and eczema are completely different diseases, they can look very similar, even under a microscope, and sometimes dermatologists have to use their entire experience to distinguish one disease from another.
Now, researchers from Germany, who have studied in detail the molecular mechanisms of the development of psoriasis and eczema, suggest using a two-gene test, which allows you to make a diagnosis with 100% accuracy.
Researchers at the Helmholtz Center (Helmholtz Zentrum) and Munich Technical University (Technische Universität München, TUM) reported on their development on the pages of the journal Science Translational Medicine.
Psoriasis and eczema are non-contagious inflammatory skin diseases that manifest as itchy red spots. But psoriasis can also be a systemic disease that affects other organs..
In their article, scientists tell how diverse the skin manifestations of both diseases can be, and how difficult it is for a doctor to visually distinguish them in some cases. At the same time, the genes involved in these diseases are completely different. This is probably why previous attempts by various researchers to compare psoriasis and eczema at the molecular level have not been successful..
In the course of their work, the team took a different approach - they looked for genetic differences in the cells of patients with both diseases. Using tissue samples from 24 patients with eczema and psoriasis, scientists identified genes and signaling pathways that are unique to each disease..
Study co-author Fabian Theis, professor at the Institute for Computational Biology at the Helmholtz Center, says they “were able to weed out genetic and environmental factors by collecting a detailed picture of the development of both diseases”.
Among other differences, it should be noted that psoriasis-specific genes are simultaneously important regulators of glucose metabolism, while eczema-specific genes are associated with the epidermal barrier and innate immunity.
From a further analysis of the two selected genes - NOS2 and CCL27 - the scientists concluded that a reliable genetic classifier of diseases could be created. Then they showed on a larger group of patients that using a test for these two genes, it is possible to accurately diagnose all 28 cases of eczema and 25 cases of psoriasis, without making a single mistake.
“This test also helped to refute the initially incorrect diagnoses made by doctors in the traditional way in especially difficult cases,” the researchers noted..
Scientists hope that a test based on a new bi-gene classifier of diseases will exclude the further appearance of such errors in clinical practice and eliminate unnecessary costs and stress associated with them..
In recent years, many specific highly effective treatments for eczema and psoriasis have been developed, but they are effective only in one of these diseases, and they cost a lot of money. In the United States, each of these highly effective treatments costs tens of thousands of dollars per patient per year..
Researchers are also going to create another test that can compare healthy and diseased skin samples. They say that these discoveries are a huge step towards the introduction of personalized medicine in dermatology. Similar things are already being introduced in oncology, where doctors can now test for genetic mutations of cancer cells and predict cancer sensitivity to chemotherapy.