Update on Hidradenitis Suppurativa (Part I): Epidemiology, Pathogenesis, Severity assessment and Comorbidities

Hidradenitis suppurativa (HS) is as a chronic, inflammatory and recurrent skin disease of the hair follicle. Prevalence of HS is a matter of debate, with estimate rates as low as 0.00033% and as high as 4.1%. HS prevalence appears significantly higher in women and has a mean age of onset in the early 20s. The primary histopathologic event seems to be a follicular hyperkeratosis with plugging, dilatation and rupture of the hair follicle resulting with subsequent inflammation and formation of abscesses and sinus tracts. The cause of this is likely multifactorial, involving genetic factors, cigarette smoking, mechanical stress, obesity, immune aberrant response and hormonal abnormalities. HS, as a chronic inflammatory dermatosis, is associated with a variety of concomitant and secondary diseases such as metabolic syndrome, inflammatory and rheumatologic diseases, depression and malignancy, and, for this reason HS management often requires a multidisciplinary team.