Psoriasis – complex mechanisms of pathogenesis and comorbidity: Do we know everything?

Psoriasis is a chronic non-infectious immune-mediated skin disease, which is an important problem for modern medicine. More than 60 million people in the world suffer from psoriasis. This disease worsens the quality of life of patients, can lead to the development of depression, social isolation and disability of patients. Despite the long history of psoriasis studies, scientific research continues to discover new mechanisms of pathogenesis. Psoriasis is associated with genetic disorders and trigger factors of the external and internal environment. The disease is complex and multifactorial. Various immune-dependent cells, cytokines, interleukins are involved in the pathogenesis of psoriasis. Numerous scientific papers have been published on pathological changes in the skin and intestinal microbiota in patients with psoriasis. The “gut-skin” axis is a new concept of the interaction between skin diseases and the microbiome through inflammatory mediators, metabolites and the intestinal barrier. Researchers have shown that disturbances in the balance of the intestinal microbiome are associated with autoimmune conditions such as rheumatoid arthritis, systemic lupus erythematosus, multiple sclerosis, and psoriasis. Experiments on laboratory animals are of interest, for example, the study of mouse models of psoriasis development. An important role is played by concomitant comorbid pathology, especially metabolic diseases. A number of authors have studied the relationship of psoriasis with metabolic syndrome, diabetes mellitus type 2, non-alcoholic fatty liver disease, obesity, arterial hypertension, and chronic kidney disease. Despite numerous studies, the problem of psoriasis is still relevant and will not lose relevance in the future. This scoping literature review examines the modern studied mechanisms of etiology and pathogenesis, the influence of skin and gut microflora, as well as comorbidity on the course of psoriasis.

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