Considered a severe form of acne, hidradenitis suppurativa is a chronic skin inflammation that usually occurs deep in the skin in areas of the body with sweat glands, such as the groin or armpits. It is characterized by a combination of blackheads and red lesions that break open and drain pus, which may cause itching or sweating. As the red bumps grow in size, they can become more painful.
The exact cause of hidradenitis suppurativa remains unclear. The condition is a disorder of follicular occlusion. This begins with follicular plugging that obstructs the apocrine gland ducts and leads to perifolliculitis (inflammation around the ducts). This is followed by rupture of the follicular epithelium, bacterial infection and formation of sinus tracts between abscesses under the skin, ie the characteristic symptoms and signs of hidradenitis suppurativa.
The following are thought to play a role in the development of hidradenitis suppurativa:
Genetics hidradenitis suppurativa may affect multiple members of a family
Sex hormones apocrine sweat glands are stimulated by androgen and suppressed by oestrogen (the exact role of these hormones remains controversial)
Endocrine factors obesity, polycystic ovaries, hirsutism, acne are common findings among women with hidradenitis suppurativa
Cigarette smoking hidradenitis suppurativa occurs more frequently in smokers than non-smokers
Women are affected by hidradenitis suppurativa three times as often as men; the reason for this is unknown. The condition most commonly occurs between 20–40 years and coincides with the post-pubertal increase in androgen levels. Disease onset rarely occurs before puberty and after menopause.