Hidradenitis suppurativa (HS) is a chronic skin disease characterized by recurrent, painful, boil-like lumps (nodules) under the skin. HS affects the areas around skin folds (e.g., armpits, groin, and breasts) and where apocrine glands (a form of sweat gland) and hair follicles are found. It is not contagious, but it is recurrent. It typically manifests as a single boil-like, pus-filled abscess or hard sebaceous lumps (lumps composed of sebum, or oil, which is excreted by the sebacous glands associated with hair follicles) and may progress to painful, deep-seated, inflamed clusters of lesions with chronic seepage involving significant scarring. In most cases, the cause of HS is unknown. It is likely that it results from a combination of genetic and environmental factors. Some cases of HS have been associated with specific genes, including NCSTN, PSEN1, and PSENEN.
Hidradenitis suppurativa tends to start after puberty, persist for years and worsen over time. Early diagnosis and treatment can help manage the symptoms and prevent new lesions from developing.