Prevalence and phenotypic features of chronic spontaneous urticaria

In recent years, there has been a steady increase in the incidence of urticaria. It is believed that the etiology of urticaria is a heterogeneous disease. Chronic urticaria (HU) subtypes have common clinical manifestations but may differ phenotypically. The article describes the epidemiology, features of the phenotypes of chronic spontaneous urticaria, their diagnosis, and treatment. New data show that the prevalence of CSU is geographically heterogeneous, high in all age groups, and growing. Significant progress has been made in the study of two main autoimmune mechanisms that determine the pathogenesis of CSU. Autoimmune (autoallergic) type I CSU is associated with IgE antibodies against autoantigens, for example, thyroid peroxidase of the thyroid gland and IL-24. Autoimmune CSU type IIb is mediated by autoantibodies that activate mast cells, for example, through IgE and FcεRI, and is present in less than 10% of patients with CSU. These two types of autoimmune hypersensitivity, i.e., autoimmunity type I (also called autoallergy) and autoimmunity type IIb, are hypothesized to be the underlying mechanisms in most patients with CSU. The goal of treatment for CSU is to achieve complete control of the disease with the absence of signs and symptoms and normalization of quality of life, but the course of the disease varies significantly in response to therapy and the timing of its development. The problem of the prevalence of CSU is highly relevant; clinical and scientific information on this problem is constantly being updated. Therefore, increasing alertness to this problem among doctors of all specialties is necessary. This review aims to provide physicians treating patients with CSU with updated information on the types, prevalence, diagnostic methods of examination, and features of treatment for CSU.