Hidradenitis Suppurativa (part 1): definition, epidemiology, etiology, diagnosis.

Hidradenitis Suppurativa (HS) is a chronic recurrent skin disease characterized by development of autoimmune inflammation in the infundibulum of the hair follicle and apocrine sweat glands located in the axillary, inguinal, anogenital regions, submammary folds, near the areola of mammary glands and the umbilical region. HS is difficult to treat and has an extremely negative impact on the quality of life. HS is separated into a distinct clinical entity fundamentally different in etiopathogenesis from acute bacterial hidradenitis. The exact prevalence of HS is unknown, it varies greatly in different studies ranging from 0.03% to 4% in general population. The detection of IL-1, IL-23, and IL-17 in the lesions indicates the key role of autoimmune inflammation involving Th17-lymphocytes in the pathogenesis of HS. Risk factors include smoking, obesity, mechanical friction, genetic predisposition. The diagnosis of HS relies on three obligatory criteria: characteristic distribution, typical morphology of the lesions and relapsing, chronic disease course. There is no gold standard in assessing the severity of the disease, since all available scoring systems have many limitations, therefore many questions regarding this disease remain unsolved at present - from terminology and clear and most objective assessment criteria for the severity of the process to the development of native clinical guidelines.